MAGELLANIC PENGUIN (Spheniscus magellanicus) TALKING POINTS

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1 MAGELLANIC PENGUIN (Spheniscus magellanicus) TALKING POINTS The following items should be in the bag, if they are not let someone in education know. If you discover a new problem with any biofact (broken pieces, loose teeth, etc.), it is your responsibility to let the staff know and make a notation with the date, time and your name on the sign out clipboard. Note: Please return all items to their appropriate place on the cart, and make sure lids and bungee cords are secured. Things should be left exactly as you found them. Note: Do not try to open the Lucite containers with the food. We are trying to prevent animals from getting into the bone room. MAGELLANIC PENGUIN BAG INVENTORY Magellanic Penguin skull Magellanic Penguin egg Magellanic Penguin feathers in box and bag Magellanic Penguin femur Snowy Owl femur, for weight comparison Magellanic Penguin foot (freeze-dried) Magellanic Penguin wing (freeze-dried) Magellanic Penguin Resource Cards PENGUINS Penguins are a type of aquatic, flightless bird, resident to the Southern Hemisphere. The Magellanic penguin is one of 17 species breeding along the far southern coasts of South America, South Africa, Australia, New Zealand and the continent of Antarctica. Only one species, the Galapagos penguin of the Galapagos Islands, is found north of the equator. The species at the SF Zoo is the Magellanic penguins, named after Portuguese explorer, Ferdinand Magellan who circumnavigated the globe in1520. MAGELLANIC PENGUIN RANGE/HABITAT (see map) A South American penguin species that breeds in colonies at locations along the coasts of Argentina, Chile and the Falkland Islands. May swim as far north as Brazil in search of food. Prefer offshore islands with tussac grass or small shrubs, which are in abundance around the Falkland Islands, Tierra del Fuego and the Pacific coast of Chile. Such islands offer deep layers of soil for burrowing into, and dense vegetation offering protection from aerial predators. Climate is generally cold but warming in South American summer months that include the breeding season, September through February. MAGELLANIC PENGUIN PHYSICAL ADAPTATIONS 1. General Characteristics Penguins have a hooked bill, spiny tongue and spines on roof of mouth that help in holding and swallowing slippery prey such as small fish, crustaceans, krill, and squid. (see photo) At SF Zoo they are fed herring and capelin, a small forage fish of the smelt family. San Francisco Zoo 11/26/14

2 Like many seabirds, penguins possess a salt gland, which allows them to drink seawater, and excrete the excess salt. (water at SF Zoo pool is fresh; penguins fed salt tablets.) Paddle-like wings used for flying through the water, together with a smooth, streamlined shape allows them to reach speeds over 15 mph. and to dive as deep as 300 Penguins have solid bones, reducing buoyancy helping them to dive for food. They are not as light as a mammal bone of similar anatomy. (compare weights of bones) Webbed toes and short tail assist as rudders for quick changes of direction. Penguin eyes are adapted for underwater vision, and are their primary means of locating prey and avoiding predators. 2. Size /Weight/Lifespan Head and body length is Average weight from 7-10 pounds with males being slightly taller and heavier than females. Otherwise male & female are generally similar in appearance. Lifespan in the wild is 25 years, and up to 30 years in captivity. 3. Feathers: Counter Shading: the black & white, tuxedo coloring helps the bird hide from predators when swimming in the ocean. The white belly blends in with the bright light coming from above, making the bird hard for seals to spot. From above, the dark back blends in with the dark ocean waves. Their black and white feathering is very dense; flattened feather shafts allow tight packing with more than 70 feathers per square inch, each coated with oil for waterproofing which together with an internal layer of body fat provides excellent insulation. They have a downy underlayer of feathers, which traps air against the skin. This layer of air is warmed by the penguin's body heat. An internal layer of body fat provides yet further insulation against the cold waters. With this excellent insulation, penguins are often more in danger of overheating. To cool off during the heat of South American summer, they shed feathers around their bills. You may see a pink area around their eyes when this happens. When penguins get too hot, they can pant like dogs and stand with their flippers extended to catch a breeze. Magellanic penguins undergo an annual catastrophic molt, lasting about 19 days during which they are confined to land and unable to replenish fat stores. 4. Counter-current Heat Exchange: Blood vessels running to and from the feet of penguins are organized to facilitate countercurrent heat exchange. Arteries carrying warm blood toward the feet run alongside veins carrying cool blood up from the feet. Heat from the out-flowing blood in the arteries is transferred to blood in the veins. Thus, cool blood moving toward the heart is warmed helping to maintain core body temperature. The warm blood moving toward the feet is cooled, keeping their feet at temperatures just above freezing. A similar heat exchange occurs with air flowing in and out during respiratory exchange. San Francisco Zoo 2

3 MAGELLANIC PENGUIN BEHAVIORAL ADAPTATIONS 1. Lifestyle Magellanic penguins often travel in large groups when searching for food. Swimming penguins often swim by popping out of the water to gulp air and plunging back into the waves. This kind of swimming is called porpoising. Porpoising is less energy efficient than staying completely submerged, but it has the benefit of allowing the birds to breathe more regularly. Porpoising may be used to confuse and disorient both predators and prey. Their wide range of vocalizations (moo, bleat, cackle, and two-toned bray) may be important for locating mates and chicks. 2. Breeding/Reproduction/Parental Care During the breeding season, Magellanic penguins gather in large nesting colonies, digging underground burrows or making shallow nests under bushes with up to 20 nests per 20 square yards. They vacate their nest sites in winter, but use them again each year. Magellanic penguins are generally long lived and form monogamous pairs that may go through 20 or more breeding cycles in a lifetime. They lay one - two eggs, but usually only one chick survives to adulthood. Living in burrows provides protection from both predators and cold weather while parents are away feeding. Both parents incubate eggs then care for the chicks, taking turns finding food and regurgitating it for their young. Eggs are incubation for days. By the end of 30 days the chicks have developed their mesoptile plumage (one of the second set of down feathers in a bird having two sets), and are able to venture out of the burrows. Chicks look very different from the adults, being a brown-grey above, creamy white below. (see picture) They develop adult plumage at about one month old and at days old they are ready to head out to sea. PREDATION Predators of adult Magellanic penguins include sea lions, leopard seals, orcas and their chicks are preyed upon by kelp gulls, skuas, and giant petrels. MAGELLANIC PENGUIN CONSERVATION ISSUES There are approximately 1.3 million pairs of wild Magellanic penguins on the coasts of Argentina and Chile, The large breeding colonies are vulnerable to oil spills, destructive guano mining (for the manufacture of fertilizers) and declining fish populations. Oil pollution alone is thought to kill more than 42,000 penguins every year along the Argentine coast. Comparisons of colonies in the Falklands, Chile and Argentina confirm that competition with commercial fishing is the major cause of the decline in Falkland Islands populations. El Nino Southern Oscillation events may cause considerable disruption to breeding cycles, as fish stocks (that parent birds depend on to feed chicks) change drastically during El Nino. With global climate change, penguins may be in serious danger as shifts in the marine food web directly affect these amazing predators. As a result, Magellanic penguins are currently considered near threatened. San Francisco Zoo 3

4 The Wildlife Conservation Society (WCS) has been working with local partners in coastal Patagonia since the 1960s, helping to conserve Magellanic penguins and other key wildlife by protecting their breeding sites and managing their populations. MAGELLANIC PENGUINS AT SF ZOO The San Francisco Zoo maintains the largest and most successful breeding colony of Magellanic penguins in captivity, having fledged approximately 205 chicks since 1985, and participating in a nationally-coordinated Population Management Plan (sponsored by the Association of Zoos and Aquariums). SF Zoo born chicks go to fish school where keepers teach them to take fish by hand thus assuring adequate nutrition and allowing for monitoring their health. Eggs hatch in May around Mother s Day at the Zoo. San Francisco Zoo 4

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