WAVES

A long way from the ocean!

2008-01-17T07:32:00.000-08:00

Addendum K. Wild Arctic Station, the Franklin Research Institute

Welcome to Wild Arctic Station: looks like you made it safely here after that somewhat hazardous ride here. On behalf of the Franklin Research Institute, studying some of the animals that live here, let me point out a few facts. First of all, my name is BERT, and I am one of the researchers stationed here. I will say a few words, answer any questions you might have, and send you off to view the other exciting animals that we have here at Wild Arctic Station.

Before I launch into my talk on the animals, let me point out a few safety considerations for the personal well being of yourself and the animals that live here.

Be conscious of any “loose” items you have: that includes keys, sunglasses, cell phones, digital cameras, and any other “objects” that are valuable to you. If they should happen to fall into the water, it will take a lot of excitement, concern, coordination, and time in order to recover; just be super careful.

This means that you should not sit or stand on the ledge of the railings.

Any food or drinks that you have should have already been discarded before you entered into the “exciting ride” here.

In this Beluga exhibit, there are 3 of these white whales. Ferdinand, Ruby, and Allua, with the male weighing in around 2000 pounds, nearly 13.5 feet long, and the two females are each about 1300 pounds, and Ruby is 11.4 feet long while Allua is shorter at nearly 11 feet long. Ferdinand is 37 years old, Ruby 29, and Allua is the youngest at around 23 years of age.

The Beluga whales here are true whales, belonging to the group called Cetacea, all of which are large aquatic mammals that have forelimbs modified into flippers, a tail that is flattened horizontally, a nostril at the top of the head for breathing (called a blowhole), and no hind limbs externally. This group contains all the whales, dolphins, and porpoises. This group is further subdivided, based on whether they have teeth (and thus eat larger animals) or whether they have a filtering, comb-like structure called a baleen, which allows these to eat smaller, shrimp like animals. The Beluga is in the former group.

The Beluga’s closest relative is the narwhal, which also lives in the Arctic like the Belugas. Both of these whales do not have a dorsal fin (the fin positioned on top of the body), the pectoral flippers are small but broad, and the neck vertebrae are not fused as they are in the other whales. This allows the Beluga and the narwhal to be much more flexible and greater mobility of the head than the other whales.

Belugas are found in shallow coastal waters, often in waters barely deep enough to cover their bodies. You can see that the absence of a dorsal fin is of advantage to these whales, as they skim just below the ice in search of breathing openings; they are also one of the only whales that can swim both forward and backward, which allows them to get into enclosed waters from which they can “back out” and free themselves.The lack of a dorsal fin also means that they have less surface area for the loss of body heat, which assists them in their thermoregulation.

The world population of Belugas is estimated to be about 60,000-80,000 animals.

The colors of a Beluga whale is dark gray to bluish or brownish gray when first born, becoming darker after the first month or so. Thereafter, they gradually become paler, due to the lessening of black color pigments in their skin. As adults, they are the stunning white that you see in our 3 Belugas.

The melon is a rounded structure on the top/dorsal part of the whale’s head, just in front of the blowhole. You can observe that the melon is very prominent and hangs over the rostrum/nose area. This melon is composed of fats. It is known that the melon facilitates sound production, as it changes shape when the whale is producing sounds.

The blowhole is single, and it is covered by a muscular flap. The flap provides a water-tight seal, so that when the animal is swimming underwater, no water enters the blowhole. When the animal gets to the surface and needs to “breathe,” it then can force the flap to open so that it can exhale and inhale.

Beluga whales have a well developed sound reception system, acute vision both in and out of the water, a social sense of touch as they are known to seek out other Belugas for physical contact.

In general, Belugas are slow swimmers. They commonly swim around 2-6 mph, but are capable of sustaining a maximum speed of over 13 mph for as long as 15 minutes. They are highly maneuverable rather than being high speed swimmers.

Since the Belugas live and feed on fishes primarily in shallow waters, they do not need to dive to deep depths nor stay submerged for long periods of time. But, under experimental conditions, they have been made to dive down to depths deeper than 2000 feet, and though most of their dives are less than 10 minutes, they can stay under for more than 15 minutes.

Belugas, like the other whales, are well adapted for the marine world. They contain blubber for insulation, which allows them to maintain their warm-bloodedness as a mammal. In order to make their diving periods be extended, the heart rate slow down, thus requiring less energy, once they submerge.

Blood is shunted away from the peripheral areas and confined to the internal, vital organs, so that those organs are well oxygenated during a dive. The muscle areas do contain a second type of respiratory pigment called myoglobin, which serves as a storehouse of oxygen that can be released in the course of an extended dive once the original supply of oxygen becomes diminished since that is not replenished by more blood.

One very interesting part of the physiology of a Beluga whale, as is true for most of the other whales, is that while it sleeps, it only goes through deep sleep in one hemisphere of the brain at a time.

Can anyone tell me what a group of whales are called? Yep, a pod is a cohesive social unity, containing 2 or more animals, usually up to 25 individuals. The average pod size in Belugas is around 10.

One of the most common Beluga behaviors is vocalizing. They rely on sound production and reception to navigate, communicate, locate breathing holes, and hunt in dark and/or murky waters. At least 11 different vocal sounds produced by Belugas have been documented, including high pitched, resonant whistles and squeals, clucks, mews, chirps, trills, and bell like tones. There is a demonstration in this exhibit hall that allows you to hear some of these sounds. Since the larynx of toothed whales do not have vocal cords, the sounds are produced by movements of air between nasal sacs in the blowhole region.

Beluga whales are opportunistic feeders. This means that they can prey upon more than 100 different kinds of primarily bottom-dwelling animals, such as octopi, squids, crabs, snails, sandworms, and fishes such as cod, herring, smelt, and flounder. Here at Sea World, they are fed frozen fish, but their diet is varied to include squid as well. They eat approximately 3% of their body weight per day, which means these receive about 50 pounds per day.

Beluga whales probably live 25-30 years in the wild; the ones here at Sea World are older than most Belugas in nature, and they appear to be very healthy.

Having Beluga whales at Sea World provides us with the opportunity to learn about the animals and how human activities impact their survival. In the protected environment of Sea World, scientists can examine aspects of their biology that are difficult or impossible to study in the wild.

For those of you who want a special interaction with Belugas, stop off at the Wild Arctic Gift Shop before you leave this exhibit and inquire about this special program that has just recently been introduced. You will have a chance to be with the trainer and animal care person by the poolside, touch the belugas, and have this very special once in a lifetime experience that you cannot get out in the wild.

The Wild Arctic adventure, however, does not stop with the Beluga whales. As you continue through the exhibit, you will come face to face with polar bears and walruses.

Polar bears are found throughout the Arctic; it is the only bear that is considered to be a marine mammal. They probably are derived from some ancestral brown bear, as polar bears and brown bears are very closely related. In fact, when they are cross bred, they can produce fertile offspring!

v Polar bears, like all other Carnivores, which include bears, dogs, cats, raccoons, otters, and weasels, have well developed claws, strong facial musculature, and specialized teeth. The canines are long, sharp, and well developed.

v Polar bears are among the largest land carnivores, comparable in size to the grizzly bear. Male polar bears grow 2-3 times larger than the females (males between 8-10 feet long and weigh 600-1300 pounds; females 6-7 feet long and 330-660 pounds). The 3 that are here at Sea World are all 12 years old (2007) and include Charly, over 1000 pounds and the lone male, and Snowflake and Szenja, each around 625 pounds. At birth, cubs weigh only about a pound and a half!

v They live in an exhibit area of around 90000 gallons, with a depth of 12 feet, as compared to the area of the beluga habitat of 460,000 gallons and 18 feet in depth. The walrus habitat contains 120,000 gallons at a depth of 16 feet, but most of the time, you will see the walruses playing in the shallow ledge right next to the acrylic panel.

v The Polar Bears are fed about 8-20 pounds of food per day for each of them. Their diet includes meat, fish, biscuits, fruits, vegetables, and a variety of other foods.

v The skin of polar bears is black, with the fur being translucent, although often mistaken for being white. The fur provides insulation and camouflage.

v The sharp claws and stiff hairs on the pads of its paws provide good traction on ice.

v The polar bear has a short tail and small ears that help reduce heat loss, as well as its relatively small head and long, tapered body for streamlining while swimming.

v It depends mainly upon the pack ice and the marine food web for survival. It is circumpolar in and around the Arctic Ocean, with the southern range limited by pack ice. Population estimates number over 20,000.

v It feeds mainly on seals, especially ringed seals that poke holes in the ice to breathe, but will eat anything it can capture, including birds, rodents, shellfish, crabs, beluga whales, young walruses, and an occasional musk oxen or reindeer.

v Orcas are their main predators in their environment.

v Polar bears are crafty hunters and will wait by the breathing holes of the seals (which are their main food) in the ice for them to surface. Sometimes they will crawl up to sleeping seals, stopping if the seal wakes, then resuming only to finally leap to catch them.

v Global warming leads to the melting of the sea ice on which the polar bears are heavily dependent.

v The longevity in nature is unknown, but they can live for more than 40 years in captivity.

The third large marine mammal you will observe in the Wild Arctic Exhibit is the walrus. There are 4 of them here: Obie, the only male, by far the largest at 3400 pounds, and 20 years old; Kitkatska is the large female, weighing 1750 pounds and is 26 years old; the 2 pups are both females, Tessa, born in 2004, and weighing 260 pounds, and Bocce, born in 2005, and weighing 120 pounds. You might not see these 2 pups all the time as they are secretive and not as bold as Obie or Kitkatska.

Those of you who have gone to Pacific Point, with the narration given for the seals and sea lions probably were informed that the order Pinnipedia, which means “fin footed animals”, contain the seals, sea lions, and the walrus. Morphologically, the walrus more closely resembles the true seals, like the harbor seal, whereas in behavior, they are more like the sea lions, or the eared seals. There are 2 subspecies of the walrus, which are geographically isolated from each other. One lives in the Pacific Ocean, like the ones we have here at Sea World, while the other is found in the Atlantic Ocean. The Pacific form is larger, with longer tusks and a wider skull. The common name, walrus, originated with the Danish word, hvalros, meaning “sea horse” or “sea cow.” The Russian word for walrus is morzh. Arctic natives call the walrus aivik or aivuk.

Distribution and habitat:

Walruses are circumpolar, but they are concentrated in geographically separate areas, with little or no chance of interbreeding.

The Pacific forms inhabit the Bering, Chukchi, and Laptev Seas, while the Atlantic walruses inhabit coastal areas of NE Canada and Greenland.

Most walruses live where the air temperature is about 5-41 degrees.

They are found where the water temperature is o more than 260 feet deep.

They prefer a habitat with a gravelly bottom. They spend 2/3 of their lives in the water, but they do haul out to rest and to bear their young.

Walruses are adapted to a habitat of sea ice and prefer snow covered moving pack ice or ice floes to land. They haul out on small rocky islands when ice is not present.

The walrus migrates following the extent of the ice pack. Throughout the year, they occur primarily in or near the southern periphery of the pack ice. They migrate primarily by swimming, but they have been observed riding the ice floes as well. Some of them are known to migrate for more than 1800 miles each year.

The total estimated population in the world is about 250,000 animals, with the Pacific form containing most of that, estimated at 200,000 in 1990. This form has been hunted to depletion and allowed to recover several times. After the last depletion in the 1930s, walruses were given protection by Russia, the state of Alaska, and the U.S. Federal Government. This protection led to the eventual recovery of the Pacific walrus population, and they have since reoccupied areas where they had not been seen for several years.

By the early 1980s, Pacific walruses appeared leaner. They increased their consumption of alternate foods such as fishes. Natural mortality increased, and birth rates decreased. This evidence suggests that the Pacific walrus population may have approached the carrying capacity of its environment.

Physical characteristics:

The males weigh about 1700-3700 pounds, and they are about 9-12 feet long.

Females are slightly smaller, weighing 880-2750 pounds and lengths of 7-10 feet.

The Atlantic forms are slightly smaller, with males weighing about 2000 pounds and lengths up to 8 feet.

A walrus has a rounded, fusiform body.

Their coloration is cinnamon brown overall. They appear quite pale in the water; after a sustained period in very cold water, they may appear almost white. They are pinkish in warm weather because the tiny blood vessels in the skin dilate and circulation increases. This increased circulation sheds excess body heat.

Calves at birth are ash gray to brown. Within a week or two, calves become tawny brown. The coloration pales with age, so that the younger individuals are darker.

Their limbs are adapted as flippers, which are hairless. The skin on the soles of a walrus’s flippers is thick and rough, providing good traction on land and ice.

The foreflippers/pectoral flippers have all the major skeletal elements of the forelimbs of terrestrial mammals, but the arm bones are shortened and modified. Each foreflipper has 5 digits of about equal length, and each digit has a small and inconspicuous claw. While swimming, the walrus holds its foreflippers against its body or uses them for steering. On land, a walrus holds its foreflippers at right angles to the body for walking.

They have triangular shaped hind flippers. The hind flippers also have 5 bony digits. The claws on the middle 3 digits are larger than the two outer claws.

The walrus uses alternating strokes of their hind flippers to propel themselves in the water, much like the true seals.

However, like the sea lions/eared seals, the walrus can rotate their hind flippers under their body, enabling them to walk on all fours.

A walrus’ head is square and broad, with conspicuous tusks and whiskers/vibrissae. There are 400-700 vibrissae in 13-15 rows on the snout. Vibrissae are attached to muscles and are supplied with blood and nerves, and are especially sensitive to touch.

Most walruses have 18 teeth, with the 2 canines in the upper jaw modified into long, ivory tusks. Both the males and females have tusks. Those of the male tend to be longer, straighter, and stouter than those of the females. These tusks can grow to lengths of more than a yard (39 inches in males, 32 inches in females). The primary functions of the tusks appear to be in establishing social dominance and for hauling out onto ice or rocky shores.

Like the seals, there are no external ear flaps, just an auditory opening.

The paired nostrils are located on the snout above the vibrissae, and they remain closed during the dive in the resting state.

A walrus’ skin is thick and tough. It may reach a thickness of more than 1 ½ inches, being thickest on the neck and shoulders of adult males, where it protects the animal agains jabs by the tusks of other walruses.

Hair is about ½ inch long over most of the body, being shortest on the face and absent on the flippers. They thin out with advancing age.

Senses:

v A walrus’ hearing is probably sensitive. Eskimos imitating walrus sounds have obtained responses from walruses more than a mile away.

v Their eyesight is probably not as acute as those of the seals and sea lions. This is probably due to their feeding on bottom-dwelling animals, where acute vision is not necessary for survival.

v Walruses seek out physical contact with other walruses. The vibrissae are extremely sensitive tactile organs, and studies indicate that a walrus can discriminate the shape and size of an object using those vibrissae.

v Walruses prefer certain foods, but researchers do not know how acute the sense of taste is or how important it is in food preference. Walruses have fewer taste buds on their tongues than terrestrial mammals.

v The sense of smell in air is well developed. It probably functions in the mother/calf recognition, for sensing approaching predators, or for sensing other walruses while hauled out.

Adaptations for the aquatic environment:

Ø Normal swimming speed for walruses is about 4 mph, but they can make short bursts of more than 20 mph.

Ø They normally breathe at the surface for about 1 minute after every 5-8 minute dives. They can stay submerged for about 10 minutes.

Ø Because their prey usually inhabit waters no more than about 250 feet deep, a walrus generally dives no deeper than that. However, deeper dives have been documented.

Ø Like the other marine mammals, they have other special physiological adaptations for diving, such as increased blood volume, increased concentrations of myoglobin in the muscles, peripheral shunting of the blood,

and slowing of the heart rate when submerged.

Ø Walruses thermoregulate with the presence of blubber and the shunting or dilation of peripheral blood vessels.

Behavior:

Walruses are among the most gregarious of animals. They exhibit social behavior all year and congregate by the hundreds. They haul out in herds, seldome hauling out alone, with the males and females forming separate herds.

Social dominance is well established in herds and subgroups. Dominance is established by tusk length, body size, and aggressiveness. The largest walrus with the longest tusk is the most aggressive and generate threat displays most often.

A male will fight with another male if it intrudes upon him during a courtship display. These fights often result in physical injury, and the frequent scars and lacerations are visible on the necks and shoulders of adult males after the breeding season. The males produce bell like sounds and other vocalizations as part of a courtship display.

Walruses can produce sounds both above and below the water. They are among the most vocal of the pinnipeds, producing growls, taps, knocks, grunts, barks, soft whistles, rasps, and clicks.

Food and foraging:

o Walruses prefer mollusks, mainly bivalves such as clams. They also eat many other kinds of benthic invertebrates, including worms, gastropods/snails, cephalophods/octopi and squid, crustaceans/shrimps, sea cucumbers, and other soft bodies animals. They may occasionally prey on fishes such as cods.

o They may feed on the carcasses of young seals when food is scarce. There are some rare but habitual seal eating walruses, with their diet consisting of ringed and bearded seals. These are usually male walruses, recognizable because they are usually larger than other males, with powerful shoulder and chest muscles. Their skin may become grease stained from the blubber of the seals they prey on.

o These walruses each eat between 60-100 pounds of fish, clams, and squid per day.

o In the seas, they sometimes catch fish, but generally graze along the sea bottom for clams, which they suck from the shell. But their diet also includes shrimp, crabs, tube worms, soft coral, tunicates, sea cucumbers, various other mollusks, and even parts of other pinnipeds. They use the vibrissae to locate food. A walrus moves its snout along the bottom, rooting through the sediment and using those vibrissae to help detect prey. Abrasion patterns of the tusks show that they are dragged through the sediment but are not used to dig up the prey.

o They may also take in mouthfuls of water and squirt powerful jets at the sea floor, uncovering and excavating burrowing invertebrates such as clams.

o The walrus does not chew its food, but they do sometimes crush clam shells.

o Their predators are mainly orcas and polar bears, although the larger walruses are known to have killed polar bears.

o Walruses are known to live around 50 years.

o The gestation period is 15-16 months, with the calving taking place usually on the ice. Newborn calves are about 99-165 pounds, about 3-4 feet long. They nurse for 2 or more years. Here at Sea World, the calves nurse 6-10 times per day, and they are fed a formula of cream, ground fish, and clams, milk replacer, vitamins, and water, if the female is not present. Growth rates are such that they gain nearly 2 pounds daily here at Sea World.

o Walruses live to a maximum of about 40 years.

This Wild Arctic Exhibit/the Franklin Research Institute opened in 1997, and it has proven to be one of the most popular exhibits here at Sea World.

Once more, Sea World thanks you for your patronage, as your admission dollars go toward supporting our studies of these marine mammals in a way that is most difficult to duplicate in nature, and much of what we know about the biology of these animals have come about from our interaction with them.

Let me remind you once again about that special treat of being able to interact with the Beluga whales down at the water’s edge, just as the trainer is doing. Just inquire at the Wild Arctic Gift Shop for details and how you can make the arrangements to be able to do this. This especially applies to those of you with annual Passports, who come repeatedly to Sea World and want closer interaction with some of these animals, but in an entirely safe and most satisfying way. Once you stroke or feed a Beluga whale, you will never be the same, unconcerned person about their welfare in their native Arctic habitat!

NOT ABOUT PLANES BUT ABOUT SNAILS

2008-01-15T20:07:00.000-08:00

"Snails without Shells"

Many of us are familiar with snails that have a shell--the ordinary garden snail, moon snails, the black Turban snails, tiny and abundant periwinkles high in the intertidal zone, the pretty tropical black or pink Murex, and wavy-top or turbinid shell. Many of us have also seen, either at underwater film festivals or while diving, sea slugs and/or nudibranchs. These latter mollusks, or soft-bodied animals, are essentially snails that through evolution have either greatly reduced the size of the shell or eliminated the shell entirely in the adult stage of the life cycle.

Although the nudibranchs are most spectacular in their vivid colors, there are a couple of other nearly shell-less snails which are common and readily visible to divers.

One is the California Sea Hare, Aplysia californica, which is often misplaced in the genus Tethys. It is a large sea slug, often reaching lengths of nearly 20 inches; the body is brown, or mottled brown, or sometimes almost jet black. It discharges a purplish ink when disturbed. The sea hare is lacking an external shell, but it does have a thin, internal remnant of a shell. The possession of long, ear-like tentacles, which are used to detect odors and chemicals in the water, gives the common name to this sluggish, common mollusk.

The other sea slug commonly seen by many of us sea lovers is the so-called striped sea slug, Navanax inermis. This soft animal is brown, with paler brown bars and bright yellow and iridescent blue spots along the sides of the body. It grows up to 12 .5inches long and is considerably sleeker and less bloated in appearance than the Sea Hare.

Unlike the Sea Hare, Navanax is found in the quieter waters of the tidepools and especially abundant in the eel-grass covered mudflats of shallow bays and channels. The interesting feature of this slug is that it is carnivorous on other sea slugs (in fact, it even eats other individuals of its own species, being cannibalistic)! Preliminary work done at Scripps Institution of Oceanography indicates that each Navanax individual secretes a substance and deposits it along its trail on the sand or mud that repels other Navanax individuals.

The evolutionary significance of this chemical repellent is not quite clearly worked out yet, but undoubtedly this permits the effective utilization of prey within a given area without the competition or danger afforded by having another hunter in the same area.

Most underwater photographers in southern California rapidly focus on the slow-moving, often graceful and elegant, distinctively-colored nudibranchs (pronounced nude-ee-brank) as subjects for a slide series. These are truly snails without shells, although a small, coiled shell is always present in the embryo. They do not have true gills, and the respiration is carried out either through the body surface or through gill-like structures on the back of the animals.

These gill-like structures, called cerata or branchiae, exposed on the back of the animal, give the animals the general name of nudibranchs, meaning "naked gills."

There are two general groups of nudibranchs: the aeolid group and the dorid animals. These can be differentiated by the pattern of distribution of the cerata. The aeolid ones have these "gills" scattered as a fringe along the sides of the animal, or scattered in several groups along the back, or spread evenly throughout the back; the dorid type has these structures gathered together in a tree-like cluster on the posterior or rear part of the back.

There are distinctive family groupings within each type of nudibranch, but for our purposes of identification, the categories of nudibranch--aeolid or dorid type--genus and species or common name should usually suffice.

Nudibranchs are most often found in the quiet waters of tidepools, or at deeper depths. A favorite observation trick for the hardy nudibranch-chaser is that of getting up at 4 a.m. and hitting the tidepools at a minus tide before dawn, especially in the spring months. Of course, many of us divers have taken the easy way out and get up at 9 a.m., go on a dive to Scripps Canyon in the middle of the day, and find these gorgeous creatures in abundance along the vertical walls.

These often brightly-colored animals are found creeping along the various attached algal plants on the bottom, feeding on the hydroids (anemone-like creatures) on the blades of the plants, or on sponges encrusting rocky areas. Occasionally, one sees a nudibranch in the water column, swimming by violent convulsive and jerking motions; this is most commonly observed with the abundant purple and orange nudibranch, Flabellina iodinea, commonly called the Spanish Dancer because of this behavior.

All nudibranchs are apparently carnivorous, mostly feeding on the hydroids and sponges already mentioned. Thus, in collections made for his scientific categorizations of nudibranchs at Scripps, James Lance takes special care to collect the hydroids or sponges in the immediate area that the nudibranch was found. Jim is the acknowledged world-authority on nudibranchs, especially with the Californian forms. He has an extensive slide collection of over 105 species, and can answer virtually any question one might pose on nudibranchs. He can be contacted at Scripps Institution of Oceanography; undoubtedly, he will invite you along on one of his insane early (pre-dawn) trips to the local tidepools.

The aeolid nudibranchs have been detected with stinging cells in the tips of the cerata. Experiments have demonstrated that these stinging cells are derived from the hydroid food animals as they are present when these hydroids are part of the diet and absent when the hydroids are withheld from the diet.

It is obvious that the feeding of these nudibranchs somehow keeps the stinging cells of the hydroids from discharging and these cells pass through the digestive system and migrate out to the ends of the gill-like extensions along the back of the animal. These stinging cells then form a protective mechanism for the nudibranch. What a marvelous evolutionary maneuver to provide protection and food at the same time for these otherwise defenseless creatures!

The conspicuous colors of many of the species actually allow the animals to harmonize well with the colorful background of sea anemones, hydroids, gorgonians, sponges, and plants. Further, although work in this aspect is not definitive, it is thought that many of the species of nudibranchs are distasteful or exude an offensive odor which provides the protection from being eaten by fishes and other predators.

Along this line, there is an old published record of a Professor Herdman who experimented with various species and found that several of the larger species were left alone by fishes. He thus decided to test their palatability and ate a live specimen of a conspicuous species, Ancula cristata; he reported that "...the taste was pleasant, distinctly like that of an oyster..." Interviews with hundreds of divers and other seafood and seashore lovers offer no other opinion--no one else seems to have tasted a nudibranch!

Lest you fear that this article is going to end without identifying some of the more common and conspicuous nudibranchs other than those already discussed, be assured that your fear has proven to be real.

The verbal and written description of these colorful and camera-ready models of sea animals cannot do justice to them; rather, should you have a particular species you need identified, your best bet is to contact Jim Lance at Scripps or to find a color plate of the animal in Behrend's 1980 paperback called Pacific Coast Nudibranchs. Of course, you can always fall back on the least desirable method--i.e., by contacting me. I would have to go through books or call Jim myself, and I believe that you can gain precious time and mountains more information by working directly with those contacts yourself.

Wouldn't it be exciting some evening, especially those wintry days in San Diego when the heavens pour out their leaky aquariums, to sit around a nice fire and watch slides of 40-50 different species of local nudibranchs? Try the Underwater Photographic Society (272-1120 for more information), and you might be able to entice an artist like Fred Fischer or Dave Slidders to come and present such a show. Perhaps a nice lobster dinner or tender steak as an inducement would insure their presence.

Or, better yet, how about your own slide show, presenting it to your favorite person(s) and inviting me for the lobster dinner!!!.

DOLPHINS

2008-01-09T09:28:00.000-08:00

WELL, THIS IS NOT QUITE A BOTTLENOSE DOLPHIN, BUT IT IS THE LARGEST OF ALL THE DOLPHINS--A KILLER WHALE!

Addendum A. BOTTLENOSE DOLPHINS

Dolphins, killer whales, porpoises, blue whales, sperm whales, gray whales, humpback whales, and all the other species of whales all belong to the scientific group/order called Cetacea. This group has forelimbs modified into flippers, a horizontally flattened “tail,” 1 or 2 nostrils at the top of the head (called the blowhole) modified for breathing, and no hind limbs. There are 2 general groups of cetaceans: those with teeth and a single blowhole, called the Odontoceti, and those having a specialized structure, called the baleen, which is used for filtering small food out of the water, called the Mysticeti.

The latter group contains the largest of the whales, called the blue whale, as well as the gray and humpback whales.

At this exhibit, called Rocky Point Preserve, is one of the “toothed whales,” the Bottlenose Dolphin. The toothed whales include all the ones we call dolphins and porpoises, as well as the killer whale and the sperm whale (which is the largest of the toothed whales). In the dolphin group, there are at least 36 species/kinds of “dolphins,” including the bottlenose, pilot whales, and killer whales.

Whales probably arose 50 million years ago, from some primitive mammal (now extinct) that “tried out” the seas. 2 small rod-shaped pelvic bones, buried deep in the body muscle of the toothed whales, may be the remnants of the hind limbs of these primitive mammals. The modern forms of these toothed whales first appear in the fossil records 5-7 million years ago. Current biochemical and genetic studies indicate that some ungulates, especially the hippopotamus, may be the closest living terrestrial relatives.

Bottlenose dolphins, of which there are 2 distinctly separated kinds (Indo-Pacific and the much more common), live in temperate and tropical waters worldwide. They are usually limited to waters that vary between 50-90 degrees F. The common bottlenose is found in the Pacific from northern Japan to Australia and from southern California to Chile. They are also found offshore in the eastern tropical Pacific as far west as Hawaii. In the Atlantic, they are found from Nova Scotia to Patagonia (South America) and from Norway to the tip of South Africa. They are also found in the Mediterranean and Black seas. The Indo-Pacific ones are found in the Indian Ocean from Indonesia to Australia to South Africa, as well as the tropical and subtropical waters of the western Pacific.

There are 2 forms of the bottlenose dolphins: coastal and offshore. In general, the coastal ecotype seems to be adapted for warm, shallow waters with:

Smaller bodies

Larger flippers

Both of which suggest increased maneuverability and heat dissipation.

These frequent harbors, bays, lagoons, and estuaries.

The offshore type seems to be adapted for cooler, deeper waters: blood characteristics indicate that this form may be better suited for deep diving, and its larger body helps to conserve heat and defense against predators.

Bottlenose dolphins are not endangered. Estimates of population sizes include:

Eastern tropical Pacific—250,000

Japan—300,000 in NW Pacific

Gulf of Mexico—45,000

Western North Atlantic—30,000

Mediterranean--<10,000

Sizes:

v Between 6-12 feet in length, with weights between 300-1000 pounds.

v Adult males are slightly longer and considerably heavier than adult females

Body shape: fusiform type for streamlining and minimizing surface area to volume ratios.

Skin: smooth and “rubbery.” No hair nor sweat glands. The epidermis, or outer layer, is 10-20 times thicker than that of terrestrial mammals. The skin flakes and peels rapidly, so that a bottlenose dolphin’s outermost skin layer may be replaced as often as every 2 hours! This is almost 10 times faster than that of MAN.

Color: gray to dark gray on its dorsal/back, fading to white or lighter gray on its lower jaw and belly, providing a type of camouflage called “counter shading.” When viewed from above, the darker back blends with the dark depths, whereas when viewed from below, the lighter belly blends with the brighter sea surface. This is a response to predators.

Blubber: a layer of fat reinforced by fibrous connective tissue, making it an excellent insulating layer to reduce heat loss. It also contributes to the streamlined shape, stores calories. Fluctuates by season as well as with body size and health statu s.

Pectoral or Fore flippers: they contain the major skeletal structures of a land mammals fore limbs, but they are shortened and modified. These flippers are curved back and pointed at the tips. They are roughly about 20 inches long. The dolphins use these foreflippers for steering and braking. The blood circulation in these foreflippers also aid in adjusting for internal body temperatures.

Tail fluke: each lobe of a dolphin’s tail is called a fluke; thus, the tail is called the tail flukes. They are flattened pads of tough, dense, fibrous connective tissue but without bone, cartilage, or muscle. They measure about 24 inches each, so that the total spread of the tail flukes is about 20% of the body length. Longitudinal muscles of the back and narrow part of the body move the flukes up and down to propel the dolphin through the water.

Dorsal fin: in dolphins, this is falcate (curved back), located around the center of the back. It is made of dense, tough, fibrous connective tissue without muscles, bones, or cartilage. Although it is probably not essential, to those which have a dorsal fin, it probably lends to stability/balance; the narwhal and beluga whale do not have a dorsal fin.

Head: the rounded region of a dolphin’s forehead is called the melon. It contains fat and plays an important part of a dolphin’s echolocation.

Teeth: Conical and interlocking, designed for grasping food, but not for chewing. These dolphins have 18-26 on each side of the upper and lower jaws, for a total of 72-104 teeth. The teeth are not replaced.

Eyes: on the sides of the head, near the corners of the mouth. Glands at the corners of the eyes secrete an oily, jelly like mucous that lubricates the eyes, washes away debris, and probably helps the streamlining as it swims. Each eye moves independent of the other. The eyes provide acute vision, especially underwater. They see well in dim light, but probably are not able to discriminate colors in the blue end of the wavelengths of light.

Ears: small, inconspicuous openings, behind the eyes, with no external flaps.

Single opening called the blowhole, which has a muscular flap that provides a water tight seal when the dolphin is swimming underwater. The blowhole and areas around the eyes and mouth appear to be the most sensitive parts of the dolphin’s body.

A dolphin’s brain size relative to its body size is larger than many mammals of the same body size. A larger brain size is probably due to an increased size of the auditory regions to facilitate sound processing in echolocation. Guesses that large brain size indicate high intelligence are untested and disputed.

Hearing: dolphins have a well developed, acute sense of hearing. They have a greater and more acute hearing than MAN; the sound reception seems to occur through soft tissue and bone conduction rather than through the small, inconspicuous ear openings.

Taste: they do have taste buds, and they show preference for specific food fishes. However, the absence of the olfactory lobes in the brain indicate no have a sense of smell.

Swimming: 3-7 mph cruising speeds, with 18-22 mph maximum short bursts. They can swim fast enough at the surface to break free of the water, flying up and out of the waer and then back under in one continuous movement, which they generally repeat. This uses less energy than swimming at the same speed under water.

Breathing: single blowhole opening. Often see a mist of water being blown up into the air; this is not from water in the lungs, which it cannot tolerate, much like MAN. It is due to water that is collected on top of the blowhole, plus some water vapor condensing as the respiratory gases expand in open air. During each respiration, a dolphin can exchange more than 80% of its lung air. Exhaling and inhaling only takes about 0.3 seconds.

Diving: generally do not need to dive very deep to obtain food. Depending on area in which they live, they; normally dive to depths of 10-150 feet. They can dive to greater depths, as they have experimentally made dives to more than 2000 feet. The dives may last up to 10 minutes, with the maximum probably around 12 minutes. Adaptations for diving are: slowing of heart rate, shutdown of peripheral circulation, and presence of myoglobin.

Sleep: spend about 1/3 of each day sleeping, but during deep sleep, only one brain hemisphere is involved.

Echolocation: sense well developed, as the dolphins rely heavily on sound production and reception to navigate, communicate, hunt, and avoid predators in dark or limited visibility waters.

Ø Produce whistles and sounds that resemble moans, trills, grunts, squeaks, and creaking doors.

Ø Sounds vary in volume, wavelength, frequency, and pattern.

Ø Identity with a signature whistle. These are so distinct that a researcher can readily identify an individual dolphin by looking at their whistle shapes on a sonogram.

Ø To date, there is no evidence of a dolphin “language.”

Food: active predators, eating a wide variety of fish, squids, and crustaceans, like shrimps. They do show strong preference for certain species of food fishes, especially in an aquatic park like Sea World. They eat 4-6% of their body weight in food daily.

Social organization: live in fluid social groups. A pod is a group of unchanging composition. Establish dominance by raking: scratching one another with their teeth, leaving superficial lacerations that soon heal.

Reproduction: 5-12 years before sexual maturity. Breed throughout the year, with gestation lasting about 12 months, with calving averaging about once every 3 years. Calves are about 4 feet long, weighing 10-40 pounds. Nursing may last up to 18 months.

Longevity : probably live about 20 years in nature. Some live past 40 years at Sea World, with the oldest female being more than 50 years.

Sea World and Busch Gardens Conservation Fund. Species research and conservation; habitat protection; rescue, rehabilitation, and release.

Manatees

2008-01-07T04:12:00.001-08:00

Perhaps a manatee isn't as "lovely" as this rose pictured above, but it is a very interesting and gentle giant.

MANATEE RESCUE EXHIBIT

On behalf of the Education Department at Sea World, let me welcome you to the Manatee Rescue Exhibit. My name is BERT. I am standing under the lights, in the center of the floor space. I will give you a few tidbits of information, but I am open to your questions at any time, but especially once I am done.

ü Safety: let me point out a few safety items first of all, for your personal well being. This exhibit hall is dim, so please be careful in walking around. In case you haven’t noticed, there is a ledge in front of the acrylic panels, and I have had a number of excited folks not see that ledge and run into it. The ledge is concrete, so you cannot possibly harm it, but it can do some damage to your shin. But, feel free to sit on the ledge if you are worn out from the warmth of the outside.

ü Now, first of all, let me introduce you to the 3 manatees here at Sea World, San Diego. They are Eddie, Vail, and Webster. Their names indicate that all 3 are males/boys.

Ø Eddie is actually the smallest of the 3, and he can be easily identified by that white scar, shaped like a starburst, very close to his tail. That is where he got hit by a boat, probably the propeller, and that is the reason that he was brought in to be “rescued.” He weighs over 1200 pounds, and is slightly longer than 9 feet. Eddie is over 8 years old.

Ø Vail is the medium sized of the 3, and he can be easily identified by having 2/3 of his tail missing. Closer inspection of that area will tell you that the boat prop probably hit him 3 times, judging from the 3 slash marks in the tail area. He weighs over 1400 pounds, and is well over 9 feet long. He is almost twice the age of Eddie at 15 years of age.

Ø The largest of the manatees is Webster, and he is almost the same age as Vail, but only about a year older at 16. Webster has no scars on his body, so he is the “clean” one. Actually, Webster was orphaned when his mother was killed by a boating accident, and so he was rescued and raised to his present size. He weighs in at 1800 pounds, and is nearly 11 feet long.

ü One of the first questions that we get at this exhibit is what and how much do these animals eat?

Ø The manatees here are fed mainly romaine lettuce, as it contains virtually all the nutrients found in their native diet of the grasses that grow in the rivers. If you are fortunate enough to be here when the diver places the food in the exhibit, you will notice that the diver puts the food at the bottom, usually wedged in under that long “log” in the center section of the exhibit. Manatees typically feed on the grasses by “feeling” them on the bottom, but they can also feed on the plant material floating at the top or even in the water column between the top and the bottom. As a treat, the manatees love apples, spinach, yams/sweet potatoes, and carrots.

Ø I know that some of you are thinking, “do you mean that these large animals only eat plant material?” Yep, but a lot of it. These 3 manatees are fed around 300 pounds of romaine lettuce daily, with each eating about a 100 pounds. So, if you want to get to be the size of a small manatee, you will have to eat a lot of salad in order to get there.

Ø You will notice that these manatees have what look like whiskers at the front of their snout/nose area. These are called the fancy name of vibrissae, which are like very sensitive long hairs. These serve the manatees for “feeling” the environment, and you might notice that the manatees will “explore” the exhibit by touching their snouts to the rocks.

Ø The manatees also use the pectoral flippers (the ones toward the front of the animal on the underside/ventral surface). These are handy in “collecting” the plant material toward their mouth.

Ø When the plant food is close to their mouths, the flexible lips are used in “grabbing and guiding” the food into their mouths. Both of these methods of gathering their food can be easily seen by watching them as they feed.

Now, just an aside. These manatees have been here since 1998, being brought here after being rescued by Sea World, Orlando. They are here for “long term rehabilitation,” and perhaps someday will be returned to their native Florida habitat in fresh water. Yep, the water in this exhibit is fresh water, and the manatees simply drink the water around them when they get thirsty. The exhibit itself is housed in acrylic panels in the front for easy viewing, and you need not concern yourself with that acrylic breaking or leaking. There are over 1,000,000 liters (280,000 gallons) of water, kept at around 76 degrees F. Manatees are very susceptible to cold conditions, suffering dramatically if the water temperature falls below 20 degrees C (68 degrees F.). Some of you might think that manatees, being so large, contain a layer of blubber, which you have heard the whales have, but that is not true. Yep, they have a lot of fat, but blubber is a special kind of fat that has a lot of connective tissue in its composition, all of which makes blubber an excellent insulating material. Since the manatees always live in warm waters, never dive deep enough to get to colder waters, they do not “need” blubber, and hence have not developed a layer of blubber, only a layer of fat. That layer of fat gives the manatee some buoyancy, which makes them able to either lie on the bottom comfortably (since the body is actually heavier than the water), or swim effortlessly around. The depth of the exhibit is 12 feet, and there is ample space for all 3 manatees to move around, feed, and play and explore.

ü Manatees are mammals, which means that they breathe air (need to get to the surface to get that air), give birth to live young, nourish their young with milk, are warm blooded, with an internal temperature much like ours, and possess hair at some point in their life cycle. Being mammals, they are different from the several species of fish that you see in the exhibit. These fish, all freshwater, are placed here to lend “ambience” to the exhibit, but the fish neither are fed on or feed on the manatees. The color posters that you see on the columns readily identify the different fish, so that you can make it your study to learn those fish, especially if you are an annual passport member and return to Sea World repeatedly. If I see you the next time you return, I will ask you which one is the “alligator gar,” or the “arapaima,” or the “red-tailed catfish.” This last fish is very, very easy to pick out, as are the other 2.

ü Also, since we are giving you pointers on “self study,” as you leave this central area, make an immediate left into a blind alcove/niche, where there are very informative and easily understood writeups on several aspects of a manatee’s life and anatomy and behavior.

One question that I will receive, especially if a manatee is “resting” on the bottom, is “…how long can it hold its breath?” 12 minutes is the answer, so if you see a manatee resting/sleeping on the bottom, and it has not been 12 minutes yet, be assured that there is nothing wrong with it: it is simply being a couch potato which is one of its favorite behavior patterns. Manatees are slow moving, swimming at speeds of 2-6 mph usually, but it can get up to around 15 mph for a short distance. But, you can see how agile and graceful they are, seeming to simply glide underwater. There is no need for speed in a manatee’s world, since its food are the various grasses, which do not “run away,” and there are not natural predators in its environment. Since their food is all in shallow waters, manatees do not dive deep, and their maximum depth of dives is probably less than 30 feet.

ü Reproduction: gestation period is about 12 months, and even though the Florida manatee breeds all year around, most of the calves seem to be born in the spring and early summer. A Florida manatee female produces a single calf about every 2-5 years. Twins are extremely rare. So, you can calculate that these animals are slow in replacing or building up a population, and with the number of manatees suffering from boat interactions, they have been placed on the Federal Endangered Species list, although the state of Florida is now considering legislation that takes them off that list.

ü In fact, one of the greatest cause of mortality/injury to manatees is its human interaction, meaning that they fun afoul of boats, fishing nets, and they used to be harvested for food.

ü A fairly interesting historical fact is that ancient sailors thought that manatees were the legendary “mermaids,” but these sailors must have had too much grog and been out to sea too long.

ü Manatees have excellent eyesight, so that they can probably spot a boat from quite some distance. But, they don’t envision the boat as a threat, and hence when the boat approaches too near, in its effort to dive away, it gets struck by the hull or the prop, either of which cause damage to the manatee.

ü Manatees probably live around 50-60 years.

ü The population of the Florida manatees is estimated to be well over 3000 (3276 in 2001 census), which is encouraging since in 1997, a census determined that there were only 2,229 remaining in the wild. The passages of legislation regulating boating activity and marine mammals disturbance make it encouraging that the Florida manatee will continue to persist in its natural environment.

v Your presence today and your continued patronage at Sea World insures that programs such as Manatee Rescue, stranded Seals and Sea Lions recovery, and shark population studies are carried on. Part of your admittance fees go toward the support of these programs, which would otherwise not be able to be carried on to the degree that they now exist.

Thank you very much for your visit to Sea World. For those of you who are annual Passport members, schedule a trip to Sea World at least monthly, get to know the different species of marine and fresh water animals that are featured here, and if you run out of animal species to identify, then start working on the many, many kinds of plants that abound in the park. The Horticultural Staff here at Sea World pride themselves in growing the lovely flowers and luxuriant foliage that you notice as you stroll through the part, going from one exhibit to the other.

Some other notes on Manatees:

They belong to the order SIRENIA, along with the dugong. All sirenians are found in warm tropical and subtropical waters. There are actually thought to be 3 species of manatees: the West Indian (the Florida and Antillean); West African (western coast of central west Africa); and Amazonian (the only one confined to fresh waters in the Amazon Basin, chiefly in Brazil). The dugong is more closely related to the now extinct Stellar Sea Cow, which became extinct in a mere 27 years after European fur traders discovered their population along the west coast of North America and hunted them for food. The Greek name for this order is derived from the “sirens” of Greek mythology. Sirens were sea nymphs who lured sailors/ships to their island with their mesmerizing songs, often causing those ships to collide with the shallow reefs.

The dugong is found in the Indian and western Pacific Oceans. The lone species left is the sole representative of the Dugongidae.

The 3 species of manatees are in the family TIRCHECHIDAE.

The West Indian manatees are composed of the 2 subspecies: the Florida and the Antillean. They are differentiated by their geographic distribution and cranial measurements; otherwise, they are very, very similar. The Florida subspecies is primarily found in peninsular Florida, but extends as far north as Rhode Island (rare) and have been rescued near Houston, Texas and Mississippi. The Antillean manatees are found in patches throughout the Caribbean, Mexico, and NE South America. The southern range extends through Central America and South America to Brazil.

The West Indian manatees, which include the Florida ones, inhabit rivers, bays, canals, estuaries, and coastal areas rich in seagrass and other vegetation. They can live in fresh, saline/salt, and brackish waters, moving freely between extremes at times. They may be found in any waterway that is deeper than 3.25 feet and connected to the coast. They prefer waters with temperatures above 70 degrees, rarely venturing into deep ocean waters.

Florida manatees move into warmer waters when the water temperature drops below 68 degrees. Historically, they have migrated south into warmer waters during the colder months of the year, congregating at the natural warm water springs. Today, power plant outfalls and other warm water discharges are important winter destinations for many manatees.

Populations of all species of manatees have declined over the past 100 years due to such causes as hunting for their meat, destruction of their habitats, boating, pollution, and low reproduction rates so that recovery of numbers is very slow.

Physical characteristics;

o Adult manatees average 10 feet in length, weighing about 800-1200 pounds. Females are generally larger than males. As I have described earlier, Webster, our largest manatee, a male, is now 11.5 feet long and weighs 1800 pounds.

o The manatee’s body is streamlined, full around the middle and narrowing to a paddle shaped tail. This type of body is said to be fusiform, which is a characteristic body shape for most of the marine mammals.

o The true color is gray, although it may appear to be brownish gray. Organisms such as algae, which may grow on the skin of slow moving individuals, alter the body color and make some manatees look more green or brown.

o The 2 small pectoral flippers (close to the head) are used for steering. These flexible flippers may also be used for bringing food to the manatee’s mouth and guding movement along a waterway ‘s bottom. They do have 3-4 fingernails at the tips of their flippers, like the toenails on an elephant’s feet. The flippers have 5 digits that are covered by a thick layer of skin. This bone structure is similar to that of toothed whales, seals, and sea lions. The alcove to your left as you leave this exhibit has an x-ray taken of the flipper that will clearly display the digits.

o The hind limbs are absent in manatees. Vestigial pelvic bones, which are not connected to the vertebral column, are found deep in the pelvic musculature, and represent the hind limbs found in other animals.

o There is no external ear flap, like those seen in sea lions. They are more like the true seals, with an auditory ear opening located just behind their eye.

o The nostrils are found at the end of the snout, as you can clearly observe. They are closed when the animal dives, and they have to be opened when the animal surfaces for a breath of air.

o They have a flexible upper lip, which helps guide vegetation into the mouth. Vibrissae/whiskers on the surface of the upper lip is attached to nerve endings and supplied with their own blood supply. They allow the manatee to “feel” their environment.

o They have 24-32 molars, located in the back of the mouth. The front molars in each row are continually worn down by the abrasive plants that the manatees eat; as the teeth wear down, new molars grow in the back of the mouth and gradually move forward. The replacement process continually provides new chewing surfaces as the teeth wear down, and continues through the manatee’s lifetime.

o In addition to the molars, manatees have horny, ridged pads at the front of the upper and lower jaws which aid in crushing plant materials.

o The tail is evenly rounded into a paddle shape and provides the major propulsion of the manatee by moving in an up and down motion.

o A manatee has hairs scattered sparsely over its body, with most of them being around the snout area.

Senses:

Hearing is not fully understood, other than that they are adapted for low frequency sounds. Hearing is an important sense for young manatees because mother and calf vocalizations are significant in keeping them together.

Manatees have well developed eyes, even though they appear to be small. In water, they can detect objects from tens of meters away. A nictitating membrane acts as an extra eyelid for protection.

Touch seems to be important for manatees. Body contact is common, especially between mother and calf. They have been observed even initiating contact with divers, and with inanimate objects such as ropes, buoys, logs, and rocks.

The manatee’s taste and smell characteristics have not been fully studied; they do have taste buds in the backs of their tongues and can most likely taste. They avoid certain plants, especially those that contain natural toxins.

Adaptations for living in an aquatic environment:

Ø They are quite agile and maneuver well under water, which you can readily observe. They have been clocked at speeds up to around 15 mph, but usually cruise at about 2-6 mph.

Ø They do not dive deep, probably less than 35 feet. This is so due to the fact that the vegetation that they feed on are all growing in the shallower depths.

Ø Their heart rate slows dramatically when diving, but they do not have some of the other adaptations that some of the other marine mammals have made for deep diving. Their muscles do not contain the higher concentrations of myoglobin for extra storage of oxygen. But, as is the case with most of the other marine mammals, they can renew about 90% of the air in their lungs in a single breath, as opposed to MAN’s 17%. While resting, manatees may remain submerged for as long as 20 minutes, although the average divers are for 2-3 minutes. More active and smaller manatees breathe more often.

Ø Manatees are nonaggressive, nonterritorial herbivores, spending most of their time feeding (6-8 hours daily), traveling, investigating objects, and socializing with other manatees.

Ø Manatees consume about 4-9% of their body weight in food daily. They feed primarily off the bottom, but they can also feed at the surface and anywhere in the water column. They have been observed cropping overhanging branches, consuming acorns, and may even haul themselves out of the water to eat bank vegetation including the leaves of mangrove trees.

Ø They require a source of fresh water for drinking. They have been seen drinking fresh water from hoses, sewage outfalls, culverts, and also congregating at river mouths. They must periodically have access to fresh water.

Reproduction:

Females may mature as young as 3 years of age, while males are usually mature by 9-10 years of age.

Cows do not form permanent bonds with bulls, and may mate with several bulls during the breeding season.

Manatees breed well in captivity, but it is not known how successful the offspring would be if released. Since space is limited at parks like Sea World, the emphasis is placed on the rehab and reintroduction of injured manatees instead of the establishment of a breeding program. All voluntary breeding programs are “on hold’ currently until the problems in the manatee’s natural environment become corrected.

Gestation is about 12 months, with most calves for the Florida manatee born during the spring and summer. A female produces a single calf once every 2-5 years. Twins are very rare. The calves are born in the water.

The calves are 4-5 feet long and weigh approximately 60-70 pounds.

The newborn calf is capable of swimming to the surface to get its first breath. They vocalize at or soon after birth, establishing the mother/calf bonding process.

Although the calves nurse for up to 2 years, they being nibbling on plants within a few weeks after birth. It is dependent on the mothers not only for nursing, but also for learning about feeding and resting areas, travel routes, and warm water refuges.

Longevity:

v They probably live for about 50-60 years.

v Although predation has not been documented, it is believed that sharks, alligators, or crocodiles may occasionally attack the manatees.

v They are susceptible to cold weather. It is not unusual for many to expire during extremely cold weather. During the exceptionally harsh winter of 2004, 50 manatees succumbed to the bad weather.

v As in any other animal population, manatees contract a variety of diseases and parasites. “RED TIDES” may also cause extreme distress in manatee populations, much like they do in seals/sea lion populations out here.

v Human impact, in the guise of watercraft accidents, flood gates and navigation locks, poaching and vandalism, accidental entanglement in fishing lines, crab lines, and those plastic wrappers used to transport 6 packs of cans, and habitat destruction, which is rapidly become the #1 human impact factor with southern Florida having a land development boom.

v All 4 species of sirenians are endangered or threatened, with the Florida manatee being the most endangered marine mammal in the United States.

Legal protection: All species of sirenians are protected to some extent by national/local acts in every country they inhabit. In the U.S., both Federal and state laws have been enacted to protect the Florida manatees. The Marine Mammal Protection Act of 1972 + the Endangered Species Act of 1973 make it illegal to capture, harm, or harass any marine mammal in U.S. waters.

Marine parks, like SEA World help the conservation effort by being authorized to rescue and rehabilitate ill, injured, or orphaned manatees. The first priority of this program is to return healthy manatees to their natural habitat. As I have already informed you, join the Sea World/Busch Gardens Conservation Fund, which sponsors lectures, seminars, legislative lobbying, and other programs that go toward the restoration of the Florida manatee population. In the last few years, the SWBG Fund has administered more than $2 million for 140 projects taking place in several countries for conservation. Find out more by visiting our customer relations counter, or go online to Seaworld.com or Seaworld.org.

Now, does anyone have any questions that we have not covered in this short talk, or that you missed due to your later arrival? Again, my name is BERT, and I represent the Education Department here at Sea World. I am located right under the lights, in the center part of the exhibit, dressed in my powder blue polo shirt, black shorts, and Yes, I am standing up as tall as I can! Have a great day here at Sea World.

Penguins

2008-01-06T11:15:00.000-08:00

This is not a photo of a penguin, but at least it is a bird.

PENGUINS

Penguins are birds, all in the class AVES. Birds:

have an outer covering of feathers,

are endothermic/warm blooded,

have front limbs modified into wings, and

lay eggs.

All living and extinct penguins belong to the order Sphenisciformes, with the single family, Spheniscidae.

Most scientists recognize 17 species of penguins: the *emperor; *king; *Adelie; *gentoo; chinstrap; rockhopper; *macaroni; royal; Fiordland crested; erect crested; Snares Island; yellow-eyed; fairly/little blue; *Magellanic; *Humboldt (not on display yet); African/black-footed; and Galapagos. * indicates the ones that are at Sea World, San Diego.

Fossil record:

40 or more species of extinct penguins.

Penguins evolved from flying birds more than 65 million years ago during the Cretaceous Period.

As the ancestors of penguins became more adapted to an oceanic environment, structural changes for diving and swimming led to the loss of flying adaptations.

To date, all penguin fossil fragments have been limited to the Southern Hemisphere. Records show that prehistoric penguins were found within the range of present day penguins.

v The earliest penguin fossil fragments were found in New Zealand in the mid 1800s.

v The oldest penguin fossils date from 58->60 million years ago.

v The largest extinct species lived in the Miocene Period (11-25 million years ago). These stood 4-5 feet tall and weighed 200-300 pounds). These measurements are approximate, since only a few bone fragments have been found.

The extinct species of penguins started disappearing during the Miocene, about the same time that the number of prehistoric seals and small whales started increasing in the oceans.

v One hypothesis is that seals, whales, and penguins may have competed for the same food source.

v Another hypothesis is that penguins could have become prey for some of these other predators.

Discovery of modern penguins:

The first European explorers to see penguins probably were part of the Portuguese expedition of Bartholomeu Dias de Novaes in 1487-88. They were the first to travel around what is now known as the Cape of Good Hope in southern Africa.

The first documentation of penguin sightings is credited to members of the Portuguese voyage of Vasco de Gama to India in 1497. They described penguins/African they saw along the southern coast of Africa.

The discovery of South America’s Magellanic penguins was chronicled during the journey of Spanish explorer, Ferdinand Magellan, in 1520.

The origin of the word “penguin” has been a subject of debate. The theories of researchers and historians range from references to the amount of fat (“penguigo” in Spanish and “pinguis” in Latin) penguins possess to the claim that the word was derived from two Welsh words meaning “white head.” The most agreed upon explanation is that “penguin” was used as a name for the now extinct great auk, which the modern day penguin resembles and for which it was mistaken.

Distribution and habitat:

All 17 species of penguins live in the Southern Hemisphere. They are found on every continent in the Southern Hemisphere. They are abundant on many temperate and subantarctic islands.

Penguins generally live on islands and remote continental regions, free from land predators, where their inability to fly is not detrimental to their survival.

These highly specialized marine birds are adapted to living at sea—some species spend as much as 75% of their lives at sea. Penguins are usually found near nutrient-rich, col-water currents that provide and abundant supply of food.

Different species thrive in varying climates, ranging from Galapagos penguins on tropical islands at the equator to emperor penguins restricted to the pack ice of Antarctica.

The seasons of the Southern Hemisphere are opposite to those in the Northern Hemisphere. When continents above the equator experience spring and summer, the areas below the equator are experiencing fall and winter.

Migration: adult penguins usually disperse from breeding rookeries to fed in coastal waters. Studies have found that adult emperor, Magellanic, and Humboldt penguins travel long distaces between feeding and breeding grounds. Young birds usually disperse when they leave their colonies and may wander thousands of kilometers. They generally return to the colonies where they were hatched to molt and breed.

Population: Data are usually gathered during the breeding season. Some researchers count chicks to estimate the total population, whereas others count breeding pairs. Estimates range from Chinstrap penguins, estimated at 4 million breeding pairs, to 4,840 mature individuals in the yellow-eyed penguin populations.

Size: the emperor penguins is the largest, standing 3.7 feet tall and weighing 60-90 pounds. The smallest is the fairy penguin, standing a mere 16 inches tall and weighing only 2.2 pounds.

Body shape: the penguin’s body is adapted for swimming, with the body shape being fusiform and streamlined. A penguin has a large head, short neck, and elongated body. The tail is short and wedge-shaped. The legs and webbed feet are set far back on the body, which gives the penguins their upright posture on land.

Coloration:

All are countershaded, dark on the dorsal surface and white on the ventral surface.

The emperor has a black head, chin, and throat, with broad yellow patches on each side of the head.

The king penguin has a black head, chin, and throat, with vivid orange, tear-shaped patches on each side of the head. The orange coloration extends to the upper chest.

The Adelie has a black head. Distinctive white eye rings appear during the breeding season.

The gentoo has a black head with white eyelids, and a distinct triangular white patch above each eye, usually extending over the head.

The top of a chinstrap’s head is black and the face is white, with a stripe of black extending under the chin, and hence its name.

The crested penguins, such as the rockhopper and macaroni, are distinguished by orange or yellow feather crests on the sides of the head, above the eyes.

The yellow-eyed penguin, as the name suggests, has yellow eyes and a stripe of pale yellow feathers extending over its dark head.

The fairy penguin, also known as the little blue, has slate-blue to black feathers and a white chin and chest.

Temperate penguins, such as the Humboldt and Magellanic, have unfeathered fleshy areas on the face and 1-2 distinct black stripes across the chest.

Chicks, juveniles, and immature penguins may have slightly different markings than adults. Generally, they appear duller in color than adults; adult markings take a year or longer to develop.

Sexual dimorphism: generally, penguins are not sexually dimorphic; males and females look alike. Crested penguins are exceptions in that the males are more robust and have larger bills than the females.

Flippers:

v Wings are modified into paddlelike flippers. The bones are flattened and broadened, with the joint of the elbow and wrist almost fused. This forms a tapered, flat flipper for swimming.

v Each flipper is covered with short, scale-like feathers. The long wing feathers typical of most birds would be too flexible for swimming through water.

v Penguins propel themselves through the water by flapping their flippers.

Head:

Different species of penguins can be identified by their head and facial markings.

Penguins have a variety of bill shapes. A penguin captures fish, squid, and crustaceans with its bill.

v Generally, the bill tends to be long and thin in species that are primarily fish eaters.

v The bill is shorter and stouter in those that mainly eat krill.

The mouth is lined with horny, rear-directed spines to aid in swallowing live prey.

Eyes:

v The color varies with species.

v Many have brown, reddish-brown, or golden-brown eyes.

v Rockhopper and macaroni penguins have red eyes.

v Fairy/little blue penguins have bluish-gray eyes.

v Yellow-eyed penguins, of course, have yellow eyes.

v The pupil of a penguin’s eye is circular. Then constricted, however, the pupils of the king penguin are square.

v Like many animals, penguins have a nictitating membrane, sometimes called a third eyelid. This is a clear covering that protects the eye from injury.

Legs and feet:

Penguins legs are short and strong.

Feet are webbed, with visible claws.

The legs are set far back on the body to aid in streamlining and steering while swimming. This placement also causes penguins to stand vertically and walk upright.

Penguins walk with short steps or hops, sometimes using their bills or tails to assist them on steep climbs.

o The maximum walking speed for Adelie penguins is 2.4 mph.

o Emperor and king penguins walk slowly and do not hop. The maximum walking speed is 1.7 mph.

o Some species, like the rockhopper penguin, jump from rock to rock.

When traveling on ice, Antarctic penguins often “toboggan” on their bellies. They use their flippers and feet to slide their bodies forward along the ice.

Tail: a penguin’s tail is short and wedge-shaped, with 14-18 stiff tail feathers. Adelie, gentoo, and chinstrap penguins have longer tail feathers (collectively known as brush tailed penguins), which they often use as a prop when on land.

Feathers:

Shiny feathers uniformly overlap to cover a penguin’s skin. Penguin feathers are highly specialized—short, broad, and closely spaced. This keeps water away from the skin. Tufts of down on the feather shafts increase the insulative properties of the feathers.

Penguins have more feathers than most other birds, with about 100 feathers per square inch.

Most species go through one complete molt per year, usually after the breeding season. The exception is the Galapagos penguin, which usually goes through 2 molts per year.

Molting is essential because feathers wear out during the year. Feathers become worn when penguins rub against each other, come in contact with the ground and water, and regularly “preen” (clean, rearrange, and oil) their feathers.

The new feather grows under the old one, pushing it out. The old feather does not fall out until the new one is completely in place. The molt is patchy and can give individual penguins a scruffy look.

During the molt, feathers lose some of their insulating and waterproofing capabilities, and penguins thus stay out of the water until their plumage is restored to optimal condition.

Depending on the species, the average length of the molt period varies between 13 days (Galapagos penguin) to 34 days (emperor).

Penguins fast when molting. Prior to this, they build up a layer of fat to provide energy until the molt is complete.

Senses:

v Hearing: as in most birds, penguin hearing is probably good, but not as acute as that of marine mammals. Hearing in penguins has not been well researched, but vocalization has since it is important for communication and mate recognition.

v Eyesight: a penguin’s eyes are adapted to see clearly both in air and under water. They have color vision.

v Taste: In general, the sense of taste in birds is poorly developed.

v Smell: a penguin’s sense of smell may be more developed than early studies indicated. The olfactory lobe of a penguin’s brain is large. Studies on captive Humboldt penguins indicate that this species may have some sense of smell.

Adaptations for an aquatic environment:

Swimming:

· Some species spend as much as 75% of their lives in the sea. They may spend several months at a time at sea, only coming ashore for breeding and molting. The Fiordland crested penguins occasionally grow barnacles on their tails, an indication that they are at sea for long periods.

· Swimming speeds generally are not well known. Earlier estimates of swimming speeds were taken from observations of penguins swimmig alongside moving ships, a method that proved to be unreliable. The fastest swimmers belong to the genus Aptenodytes. Emperors have been observed swimming 9 mph, though they normally do not exceed 6.7 mph. Both kings and chinstraps have been recorded at 5.3 mph. Adelie penguins reach speeds of 4.9 mph. Fairy penguins swim slower at about 1.6 mph.

· A penguin hunches its head into its shoulders to maintain its streamlined shape and reduce drag while swimming. It keeps its feet pressed close to the body against the tail to aid in steering.

· Penguin wings are paddlelike flippers used for swimming. The motion of the flippers resembles the wing movements of flying birds, giving penguins the appearance of flying through water. The wing and breast muscles are well developed, to propel penguins through water—a medium much denser than air.

· Having solid, dense bones helps penguins overcome buoyancy.

· Although it is more energy efficient for penguins to swim under water than at the water’s surface, they must come to the surface to breathe. Many species of penguins porpoise—leap in and out of the water, like dolphins or porpoises.

· When porpoising, penguins can continue breathing without interrupting forward momentum. They maintain a steady speed of 4.3-6.2 mph. Porpoising also may confuse underwater predators.

· Not all species exhibit this behavior. Emperor penguins are not known to porpoise and this behavior is infrequently seen in king penguins.

Diving:

· Most prey of penguins inhabit the upper water layers, so penguins generally do not dive to great depths or for long periods.

o Most species stay submerged less than a minute.

o Gentoo and Adelie penguins have been recorded staying under water for 7 minutes.

o Chinstraps can reach depths of 100 meters, but most divers are less than 30 m. Nearly half are less than 10 m. and last between 20-30 seconds.

o Most dives of king penguins last less than 4-6 minutes, although dives of nearly 8 minutes have been documented. The maximum recorded depth for a king penguin dive was 304 m/997 feet.

· Studies using radio tracking and automatic depth records reveal that emperor penguins sometimes hunt at great depths.

o Emperors hunt fast midwater squids and fishes and therefore tend to dive more deeply and remain submerged longer than other penguins.

o The deepest dive recorded for an emperor penguin was 535 m/1,755 feet. The longest recorded dive for an emperor penguin was 22 minutes. Most dives are within 21 m/70 ft of the surface and last 2-8 minutes.

· During deep dives, the penguin heart rate slows.

· Under experimental diving conditions, penguins exhibit reduced peripheral blood flow.

· The temperature of a penguin’s peripheral areas (limbs and skin) drop during a dive while those of the core regions are maintained at the normal temperatures.

Respiration: when swimming, penguins inhale and exhale rapidly at the surface. Just before a dive, penguins inhale and then dive on a breath of air.

Salt secretion: penguins have glands under the eyes that help rid the body of excess salt. The secretion of salt and fluid often collect as droplets on the bill are are shaken off. These glands are so effective that penguins can drink sea water without ill effects.

Sleep:

· A penguin typically sleeps with its bill tucked behind a flipper, which some scientists believe serves no known purpose in penguins, but is a remnant of ancestral relations to flighted birds. Other researchers believe the behavior may reduce the amount of heat lost through the face, particularly the nostrils.

· To conserve energy while fasting, penguins may increase the time they spend sleeping.

· During the Antarctic winter, when the period of darkness may last more than 20 hours, huddling emperor penguins that are incubating eggs may sleep for most of a 24 hour period.

Thermoregulation:

· The internal temperature range of penguins is 37.8-38.9 C. (100-102 F).

· Overlapping feathers create a surface nearly impenetrable to wind or water. Feathers provide waterproofing critical to penguins’ survival in water that may be as cold as -2.2 C (28 F) in the Antarctic. Tufts of down on feather shafts trap air. This layer of air provides 80-84% of the thermal protection for penguins. The layer of trapped air is compressed during dives and can dissipate after prolonged diving. Penguins rearrange their feathers by preening.

· To conserve heat, penguins may tuck in their flippers close to their bodies. They also may shiver to generate additional heat.

· A well defined fat layer improves insulation in cold water, but probably is ot enough to keep body temperatures stable at sea for long. Penguins must remain active while in water to generate body heat.

· Penguins in colder climates tend to have longer feathers and a thicker fat layer than those in warmer climates.

· The dark plumage of a penguin’s dorsal surface absorbs heat from the sun, which increases body temperature.

· On land, king and emperor penguins tip up their fet, and rest their entire weight on their heels and tail, reducing contact with the icy surface.

· Emperor penguins huddle together to conserve heat. As many as 6,000 males will cluster while incubating eggs during the middle of the Antarctic winter.

· Emperor penguins are able to recapture 80% of heat escaping in their breath through a complex heat exchange system in their nasal passages.

· On land, overheating may sometimes be a problem.

o Penguins may prevent overheating by moving into shaded areas and by panting.

o Penguins can ruffle their feathers to break up the insulating layer of air next to the skin and release heat.

o If a penguin is too warm, it holds its flippers away from its body, so both surfaces of the flippers are exposed to air, releasing heat.

o Temperate species, like Humboldt and African penguins, lack feathers on their legs and have bare patches on their faces. Excess heat can dissipate through these unfeathered areas.

· A penguin’s circulatory system adjusts to conserve or release body heat to maintain body temperature.

o To conserve heat, blood flowing to the flippers and legs transfers its heat to blood returning to the heart. This countercurrent heat exchange helps ensure that heat remains in the body.

o If the body becomes too warm, blood vessels in the skin dilate, bringing heat from within the body to the surface, where it is dissipated.

Social behavior:

Among the most social of all birds. All species are colonial

May swim and feed in groups, but some may be solitary when diving for food. Emperor penguins have been observed feeding in groups with coordinated diving.

During breeding season, penguins come ashore and rest in huge colonies called rookeries. Some rookeries include hundreds of thousands of penguins and cover hundreds of square kilometers.

Penguins exhibit intricate courting and mate recognition behavior. Elaborate visual and vocal displays help establish and maintain nesting territories.

Although king penguins are highly gregarious at rookery sites, they usually travel in small groups of 5-20 individuals.

Penguins communicate by vocalizing and performing physical behaviors called “displays.” They use many vocal and visual displays to communicate nesting territories and mating information. They also use displays in partner and chick recognition and in defense against intruders.

Individual behavior:

Navigation: studies of Adelie penguins indicate that they use the sun to navigate from land to sea. They adjust for the sun’s changing position in the sky throughout the dya.

Preening:

· Penguins preen their feathers frequently. Feathers must be maintained in prime condition to ensure waterproofing and insulation.

· Penguins preen with their bills. A gland near the base of the tail secretes oil that the penguin distributes throughout its feathers.

· Penguins preen for several minutes in the water by rubbing their bodies with their flippers while twisting and turning.

Communication:

Vocalization:

· Penguin calls are individually identifiable, allowing mates to recognize each other and also their chick. This is important because members of a large colony of penguins are nearly indistinguishable by sight.

· Research has identified differences in the calls of male and female emperor penguins. These differences probably function in courtship and mate selection.

· 3 main kinds of penguin calls:

o Contact call assists in recognition of colony members.

o Display call is the most complex of all the calls and is used between partners in a colony. The call must convey information on territorial, sexual, and individual recognition.

o Threat call is the simplest and is used to defend a territory and warn other colony members of predators.

Displays: penguins communicate by vocalizing and performing physical behaviors called displays. They use many vocal and visual displays to communicate nesting territories, mating information, nest relief rituals, partner and chick recognition, and defense against intruders.

Food and foraging:

Preferences and resources:

· Penguins eat krill, squids, and fishes. Various species of penguins have slightly different food preferences, which reduce competition among species.

· The smaller penguin species of the Antarctic and the subantarctic primarily feed on krill and squids. Species found farther north tend to eat fishes.

· Adelie penguins feed primarily on small krill, while chinstraps forage for large krill.

· Emperor and king penguins mainly eat fishes and squids.

Food intake: intake varies with the quantity and variety of food available from different areas at different times of the year. A colony of 5 million Adelie penguins may eat nearly 17.6 million pounds of krill and small fishes daily.

Method of collecting and eating food:

· Feed at sea. Most feeding occurs within 50-60 feet of the surface. The location of prey can vary seasonally and even daily.

· Penguins primarily rely on their vision while hunting. It is not known how penguins locate their prey in the darkness, at night, or at great depths. Some scientists theorize that penguins are helped by the bioluminescence capabilities of many oceanic squids, crustaceans, and fishes.

· Penguins catch prey with their bills and swallow it whole while swimming. A penguin has a spiny tongue and powerful jaws to grip slippery prey.

· Different species travel various distances from the colony in search for food. Homing areas may range from 9 miles from the colony for Adelies and 559 miles for kings. Emperor penguins may cover 102-903 miles in a single foraging trip.

· Penguins walk and toboggan from feeding grounds to rookeries. When fishing grounds are far away, penguins will feed in seal holes and other openings in the ice.

Fasting:

· Go through annual fasting periods. Prior to fasting, penguins build up a layer of fat, which provides energy.

· Prolonged periods during breeding season; they do not leave the nesting areas to feed. Some penguins fast throughout the entire courtship, nesting, and incubation periods.

· Also fast during annual molting periods. The temporary reduction in insulation and waterproofing caused by the loss of feathers during a molt prohibits penguins from entering the water to feed.

· Chicks fast near the time they are ready to shed juvenile feathers for adult plumage. Usually by this time, the parents no longer are feeding the chick. Growth stops during this fasting period, but resumes once the molt is complete.

· The length of fasting depends on penguin species, sex, and type of fasting. The kings and emperors have the longest fasting periods.

· Breeding male kings may fast for up to 54 days during courtship and the first incubation shift. Emperors may fast 90-120 days during courtship, breeding, and the entire incubation period.

Reproduction:

Sexual maturity: like most seabirds, penguins tend to be long lived. They may take 3-8 years to reach sexual maturity. With some of the smaller species, breeding may begin at 3-4 years, but most larger species are not accomplished breeders until much later. On average, breeding does not begin until the 5^th year, and a few males do not breed until the 8^th year.

Mating activity:

· Breeding seasons differ from species to species.

o Most have an annual breeding season—spring thru summer.

o Kings have the longest breeding cycle of all species, lasting 14-16 months. A female king may produce a chick during alternate breeding periods..

o Emperors breed annually during the Antarctic winter, June through August. During its breeding season, air temperatures may drop to -76 degrees F and winds may reach speeds up to 124 mph. For most of the winter, Antarctic penguins live in an environment of darkness or half light. Why emperors breed during the harshest season of the year is unknown, but some scientists speculate that when the chicks become independent 5 months later in January and February, environmental conditions are most favorable for the young birds.

o The fairy penguins breeds throughout the year and has the shortest breeding cycle, which lasts about 50 days.

o Some of the temperate penguins tend to nest throughout the year.

· Courtship: varies among species. Generally begins with both visual and auditory displays. In many species, males display first to establish a nest site and then to attract a mate. Not all species exhibit all displays, but in general, there are 3 distinct types of displays.

o Ecstatic: also called trumpeting, head swinging, or advertisement, this display establishes possession of a nest site, attracts females, and warns other males to stay away. Males at the nest sit commonly exhibit the ecstatic display before females arrive. The male may dip its head low and then outstretched and squawk or “bray.” Some, like the Adelie, chinstrap, and crested species, may swing their head or flap their flippers while calling.

o Mutual: once paired, male and female penguins perform the mutual display together. This seems to strengthen the pair bond. Similar to the ecstatic display—head and neck stretched upward with a braying vocal. Crested, brush-tailed, and temperate penguins stand facing each other, performing the action in unison. Mutual displays continue throughout the breeding season, often taking place at the nest when parents switch places for egg incubation and chick feeding.

o Bowing: bowing displays may lessen the likelihood of aggression and strengthen recognition between partners. One or both of the penguins dips its head and points its bill at the nest or at the other bird’s feet.

o Most species are monogamous during a mating season; however, research has shown that some females may have 1-3 partners in one season and some males have have 1-2 partners.

o Mate selection is up to the female, and it is the females that compete for the males.

o In some species, a female selects the same male from the preceding season to mate with.

o When a female selects a different mate, it is usually because her mate from the previous season fails to return to the nesting site.

Nesting: when it is time to breed, mature birds return to the rookery where they hatched. This results in large numbers of birds at a single rookery rather than colonizing new areas. Some rookeries number millions of birds.

Nesting habitats vary from species to species.

Eggs: white to bluish or greenish. Shape varies among species, from more or less round to pear-shaped. Size and weight varies with species: emperors eggs are 4.4-5 inches long and weight 12-18 ounces; Adelie penguins eggs measure 2.2-3.4 inches long and weigh 2.1-5.4 ounces.

The egg clutch usually contains 2 eggs (only 1 in kings and emperors).

Incubation: time spent warming the egg before it hatches. With the exception of the emperors, partners take turns incubating eggs, allowing each mate to leave to feed for several days at a time.

v A female emperor’s penguin transfers a single egg to the top of her mate’s feet. The female goes to sea to feed while the male incubates the egg. She returns several weeks later, usually just before the gg is ready to hatch, to relieve her mate so that he may feed. The male fasts throughout the courtship, nesting, and incubation periods. He lives off reserves of body fat which may be 1.2-1.6 inches thick, and loses up to 45% of his body weight.

v The incubation period varies with species. It may be as short as 1 month, or as long as 2 months (62-66 days) for emperors.

v Incubation temperature is about 36 degrees C/96.5 degrees F; a bit lower for the larger species. Emperors can maintain an incubation temperature of 31 C/87.8 F in an environment that is -60 C/-76 F.

v The greatest single cause for reproductive failure in some species is the mistiming between parents for nest relief during incubation. This usually occurs when the female fails to return from a foraging trip before the male deserts the nest. A male will spontaneously leave the nest and eggs when the motivation to feed overcomes that for incubating eggs.

v Hatching:

Ø Chicks first “pip” by poking a small hole in the egg. They then chip at the shell until they can push off the top. Chicks take up to 3 days to chip their way out.

Ø Fine down feathers cover most newly hatched chicks.

Ø Down feathers of different species may be white, gray, black, or brown.

Ø Down feathers are not waterproof, and chicks must remain out of the water until they acquire their juvenile plumage.

Ø Adult plumage is acquired at about 1 year.

v In all species, the coloration and markings of chicks separate them from adults. Scientists believe that the chicks’ coloration elicits parental behavior from the adults, and that adults do not perceive the young birds as competitors for mates or nesting sites.

v The striking coloration of emperor chicks may help to make the chicks more visible against the ice and snow, significant because emperors don’t have individual nest sites where the young can be found.

Care of the chicks:

Chicks require attentive parents for survival. Both parents feed the chick regurgitated food. Adults recognize and feed only their own chick. Parents are able to ID their chick by its distinctive call.

Male emperors exhibit a feature unique among penguins. If the chick hatches before the female returns, the male, despite his fasting, is able to produce and secrete a curdlike substance from his esophagus to feed the chick, allowing for survival and growth for up to 2 weeks.

Parents brood chicks/keep them warm by covering them with their brood patch.

In some species, partially grown chicks gather in groups called crèches. These groups provide some protection from predators and the elements.

Chick development: a chick depends on its parents for survival between hatching and the growth of its waterproof feathers. This may range from 7 weeks/Adelie to 13 months/kings. For most species, once a chick has replaced its juvenile down with waterproof feathers, it is able to enter the water and becomes independent of its parents.

Longevity and mortality:

v Longevity: the average life expectancy of penguins is ca 15-20 years, although some live considerably longer. High mortality occurs among the young.

ü Winter starvation may claim the lives of 50% of king chicks.

ü Emperor chicks may experience 90% mortality within the first year of life.

ü When mortality affects one chick in species producing 2 offspring of moderate size differences, it is usually the smaller chick that does not survive.

v Predators:

ü When in the water, penguins may be eaten by leopard seals, fur seals, sea lions, sharks, or killer whales.

ü On land, foxes, snakes, and introduced predators such as feral dogs, cats, and stoats/weasels prey on eggs and chicks.

ü Antarctic and subantarctic chicks are susceptible to predatory birds such as skuas, sheathbills, and giant petrels.

ü Gulls and ibises eat 40% of African penguin eggs.

ü Fairy penguins rely on burrows and a nocturnal lifestyle to avoid predators such as swamp harriers, peregrines, gulls, snakes, rats, and lizards.

v Human impact:

ü Indigenous peoples have hunted some species and taken eggs.

ü Mass exploitation occurred when early explorers, sealers, whalers, and fishermen turned to penguin colonies as sources of fresh meat and eggs. Sometimes, more than 300,000 eggs were taken in annual harvests from one African island. Explorers were known to kill and salt 3000 penguins in a day for voyage provisions. Penguins were easy prey because of their inability to fly and their seeming lack of fear of humans. Although egg collecting was banned in 1969, illegal harvesting continues today.

ü During much of the 19^th and into the 20^th century, penguin skins were used to make caps, slippers, and purses. Feathers were used for clothing decorations and as mattress stuffings.

ü The extraction of oil from penguins’ fat layers became economically important in the 1800s and early 1900s. Oil was used for lighting, tanning leather, and fuel. In the Falkland Islands alone, an estimated 2.5 million penguins were killed within a 16-year time span. The oil industry came to a halt in 1918 due to protests by the general public and the availability of cheaper and better quality chemical products.

ü Seabird guano has great commercial value as a nitrogen rich fertilizer. Although the Incas used seabird guano to improve their crops as far back as 500 B.C., they carefully managed the resource by extracting it at a slower rate than it was being produced. Guano became a major product of international trade in the 1800s and in the early 1900s. Guano deposits were in danger of being depleted. Guano harvesting is better managed today, but overexploitation of this commodity is a serious threat to the Humboldt penguin population, which relies on accumulated guano to dig burrows into rocky and soil-poor nesting areas.

ü In some places, such as islands in the southern Indian Ocean, fishermen still use penguin meat for bait.

ü Human competition for food sources can affect penguin populations. Overfishing for anchovetta, the primary food source for the Humboldt penguins, has contributed to penguin population declines.

ü The introduction of predators has had devastating effects in some areas. Rats, dogs, pigs, and ferrets have been known to prey on chicks, eggs, and even adult penguins. Introduced herbivores, such as sheep and rabbits, cause serious deterioration of habitat.

ü Colonies of penguins have been affected by building activities and road construction. One colony of kings at Iles Crozet (a small group of islands in the Indian Ocean) was completely destroyed. A nearby area was cleared, and, fortunately, the penguins recolonized.

ü Trash in the ocean can affect seabirds. Penguins have been known to ingest plastic or become entangled in debris, causing injury and death.

ü Oil spills affect penguins. Oil fouls feathers, reducing waterproofing and insulating properties of their plumage, making the birds susceptible to hypothermia. Penguins also ingest the oil while trying to preen, which poisons them and causes internal organ damage.

ü Traces of DDT.dichlorodiphenyltrichloroethane and other pesticides have been found in the tissues of Adelie and chinstrap penguins. Scientists speculate that these pollutants were transported by ocean currents or other animals. Their appearance in Antarctic penguins is significant in that these toxic substances have now reached the pristine Antarctic.

ü Activity that may seem harmless, such as aircraft flying over penguin colonies, may cause panic and stampedes, resulting in injury and easy predation.

ü The population of ecotourism is increasing with cruise ships frequenting Antarctic waters. Enthusiastic sightseers must be careful not to interfere with normal penguin activity by staying back and keeping noise levels down.

ü Penguins may be indirectly affected by past hunting of whales. The increase of some penguin species over the last 30 years may be attributed to the greater availability of krill following the reduction of some Antarctic whale populations. However, the commercial value of krill may encourage large scale harvesting of this resource in south polar waters, which would impact penguins and other marine animals that rely upon krill as a food source.

El Nino: this ocean phenomenon, involving a change in wind and ocean current pattersn, which warms surface temperatures and reduces upwelling of nutrient rich waters, affects plankton, krill, and small fishes, which comprise the food supply of larger marine animals. Penguin species most affected are the Humboldt and Galapagos penguins.

ü The 1982-83 El Nino caused a 65% depletion of the Humboldt population off the coast of Peru. The population partially recovered, but once again plummeted during the 1997-98 El Nino.

ü Up to 77% of the Galapagos penguins was wiped out by the 1982-83 El Nino, leaving only 463 total birds. A slow recovery began in 1985. However, a further decline of 66% of the population occurred during the 1997-98 El Nino. The population once again appears to be in a recovery phase.

Conservation:

Legal protection: all 17 species are legally protected from hunting and egg collection. At least 3 species are considered at risk.

v The Antarctic Treaty was signed by 12 nations in 1959 and reauthorized in 1991 to protect Antarctica and preserve its living resources. This treaty makes it illegal to harm, or in any way interfere with, a penguin or its eggs. Every penguin specimen collected with a permit must by approved by and reported to the Scientific Committee for Antarctic Research.

v The convention on International Trade in Endangered Species of Wild Fauna and Flora is an international treaty developed in 1973 to regulate trade in certain wildlife species, including penguins.

v The World Conservation Union: worldwide conservation organization linking together government agencies, non-government agencies, and independent states to encourage a worldwide approach to conservation.

v The Endangered Species Act, 1973. Administered by the U.S. Depts. Of Interior and Commerce, seeks to stop the extinction of wild animals and plants in the United States, other nations, and at sea. The Galapagos Penguin is listed as endangered.

Wildlife refuges:

v Protection of habitat began in the early 1900s.

v The Conservation Assessment and Management Plan seeks to evaluate the status of various animals and to determine conservation policies. In 2004, the 5^th following the conference, a 2-day collaborative workshop sponsored by SeaWorld and the New England Aquarium reviewed the 2004 fact sheets, updated the 1998 listing for all species of penguins, and looked at penguin conservation priorities and future initiatives. International Penguin Conference was held;

v Zoological parks. Most people do not have the opportunity to observe penguins in the wild. The unique ability to observe and learn directly from live animals increases public awareness and appreciation of wildlife. Currently, the 3 Sea World parks maintain emperor, king, Adelie, gentoo, chinstrap, rockhopper, macaroni, Magellanic, and Humboldt penguin species. Each has successfully reproduced within the parks’ comprehensive breeding program.

v SW-BG Conservation Fund. Seeks to encourage sustainable solutions by supporting critical conservation initatives worldwide. Grants awards 2/year to selected projects that are science-based, solution driven, and community oriented. Accepts donations to support conservation projects in the U.S. and around the world. 100% of donations go directly to selected projects. Has sponsored a number of projects on marine and terrestrial animals, including penguins: Falkland islands This project conducts a full census of all king, gentoo, macaroni, and rockhopper penguins. This will involve counting every colony where these species breed, soon after egg-laying has finished. Results will be compared to the previous censuses of 2000 and 1995 to establish the trends and fluctuations in population size of the 4 species of penguins. Penguin Census, 2005-2006.

Species:

Emperor penguin: 44 inches tall; 60-90 pounds. Circumpolar on Antarctic continent within limits of pack ice. Feed on fishes and squids. Main predators are leopard seals, killer whales, and skuas. Ca 300,000 individuals.

King penguin: 37 inches tall; 30-35 pounds. Subantarctic islands and peninsulas, usually forage in ice free waters. Feed on squids and fishes. Predators leopard seals, skuas, giant petrels, gulls, sheathbills. CA 2,000,000 adults.

Adelie penguin: 18-24 inches tall; 8-10 pounds. Circumpolar on Antarctic continent within limits of pack ice. Feed primarily on krill, but also on squids and fishes. Leopard seals, skuas, and sheathbills major predators. 4,000,000-5,200,000 individuals.

Gentoo penguin: 24-30 inches tall; 12-14 pounds. Circumpolar in subantarctic and Antarctic waters, avoiding pack ice and continental coasts, feeding on krill and squid. Skuas, leopard seal, Antarctic fur seal, New Zealand sea lions, Southern sea lions major predators. Estimated 314,000 breeding pairs.

Chinstrap penguin: 16-18 inches tall; 5-6 pounds. Subantarctic islands. Feed on fishes, squid, krill. Predators New Zealand fur seals, New Zealand and Southern sea lions, skuas, gulls. About 7,340,000 mature individuals.

Rockhopper penguin: 16-18 inches tall; 5-6 pounds; subantarctic islands, feeding on fishes, squid, krill. N.Z. fur seals and sea lions, Southern sea lions, skuas, gulls major predators. About 7,340,000 mature individuals.

Royal penguin: 26-30 inches tall; 12 pounds; Macquarie, Bishop, and Clerk Islands in the Southern Ocean. Feed on krill and squid; N.Z. fur seals, skuas, and giant petrels predators. About 1,702,000 adults, mostly on Macquarie Island.

Erect crested penguin: 25 inches tall; 6-8 pounds; breed only on the Antipodes and Bounty Islands of New Zealand, feeding on squids and fishes. Predators N.Z. sea lions and fur seals and Australian sea lions. Estimated 154,000-170,000 mature individuals.

Macaroni penguin: 20-24 inches tall; 10 pounds; subantarctic islands in the Atlantic and Indian oceans. Feed on squid and krill. Predators leopard seals, Antarctic fur seals, skuas, sheathbills. About 18,000,000 individuals.

Fiordland crested penguin: 24 inches tall, 6-7 pounds; subantarctic islands and New Zealand. Feed on small fishes, crustaceans, cuttlefish. Predators N.Z. fur seals, stoats, rail bird. Estimated 5,000-6,000 adults.

Snares Island penguin: 25 inches tall; 6-7 pounds. South of New Zealand in the Snares Islands (all within 3 sq. km). Feed on euphausiid shrimp, squids, fishes. Predator N.Z. sea lions. About 46,500 mature penguins.

Yellow eyed penguin: 30 inches tall; 3 pounds. Southeastern New Zealand, feeding on squids and fishes. Predators N.Z. sea lions and domestic predators. Estimated 4,800 mature individuals.

Magellanic penguin: 24-28 inches tall; 11 pounds. Falkland Islands and along the coasts of Chile and Argentina. Feed on small fishes and cuttlefish. Predators southern sea lion, leopard seal, Patagonian fox. 1,300,000 breeding pairs.

African penguin: 24-28 inches tall; 7 pounds. South African waters, feeding mostly on anchovies, sardines, squids, crustaceans and other fishes. South African fur seals, southern sea lions, octopus, sharks, sacred ibis, gulls major predators. About 180,000 adults.

Fairy penguins: 16 inches tall; 2 pounds; southern Australia and New Zealand. Feed on small fishes; predators Australian sea lions, fur seals, dogs, cats, stoats, ferrets. About 350,000-600,000 adults.

Humboldt penguin: 22-26 inches; 9 pounds; islands off western S.A. and along the coasts of Peru and Chile. Feed on anchovetta; predators sharks and southern sea lions. About 3,300-12,000 mature individuals.

Galapagos penguin: 21 inches tall; 5-6 pounds. Galapagos Islands, feeding on small fishes. Predators sharks, eared barn owls, Galapagos hawk, feral cats, dogs. About 1,200 mature individuals.