California Sea Lions (Zalophus californianus)
The Smithsonian’s National Zoo is home to four female California sea lions: Sidney (3 years old), Summer (7 years old), Calli (7 years old) and Sophie (1 year old). Sophie is Calli’s first pup and was born on June 17, 2011 at the Pittsburgh Zoo and Aquarium. Calli and Summer are not related, but they have similar stories. Both sea lions were orphaned as young pups: Calli’s mother died shortly after she was born, and Summer was abandoned by her mother. In June 2005, Pacific Marine Mammal Center in Laguna Beach, Calif., rescued Calli and Summer. There, animal care staff hand-raised them. They arrived at the Smithsonian’s National Zoo in spring 2006. Sophie and Sidney arrived at the Zoo in July 2012.
Husbandry training is an important part of sea lion care at the National Zoo. Keepers have trained these animals to hold still for eye exams (and to receive eye drops, if needed), dental exams, injections, blood draws, weigh-ins and radiographs. When keepers need to perform a full body check, they ask the sea lions to present flippers, open their mouths and present other body parts.
Sea lions were once hunted for their skin and oil or killed by fishermen. Under the protection of international laws, some sea lion populations have made a comeback.
Where Do They Live?
California sea lions live on and around the Pacific coast of North America, from Canada's British Columbia to Baja California in Mexico.
- Male California sea lions range from dark gray to chocolate brown in color, while females are a lighter brown.
- Male California sea lions are much larger than females, weighing as much as 1,000 pounds, and measuring up to eight feet long. Males develop a bony bump on the top of the skull at about age five. Females weigh up to 250 pounds and reach lengths of six to seven feet long.
- Sea lions have external ear flaps, large eyes, and 40 to 60 whiskers. Each long whisker, called a vibrissa, can rotate around with the underwater currents, letting the sea lion "feel" any food swimming nearby.
- Their hind flippers are shorter than their front flippers.
- Sea lions are the fastest pinniped swimmers. They can reach speeds of up to 25 miles per hour in the water.
- California sea lions are very vocal! They can bark, roar, growl and grunt.
- When they are on land, sea lions gather in large groups (as many as 1,000 individuals) and may lie near and on top of each other.
- In the water, they may float on the surface in small groups called “rafts.”
Thawed frozen squid, capelin, herring and butterfish. They are given vitamin supplements daily to replace any nutrients lost in the food during the freezing process.
California sea lions live 15 to 20 years in the wild and average 25 to 30 years in zoos.
Gray Seal (Halichoerus grypus)
The Smithsonian’s National Zoo has one gray seal named Selkie (39 years old) in its collection. In fall 2012, her daughters Kjia (22 years old) and Kara (29 years old), and an unrelated male, Gunther, will arrive at the Zoo from the Adventure Aquarium in New Jersey, increasing the Zoo’s gray seal population to four individuals. Gunther is recommended to breed with Kjia and Kara. Selkie was a true Navy seal, chosen for training to perform special missions during the Cold War. Some of the tasks she learned include using a screwdriver, turning a large wheel and retrieving equipment.
At the National Zoo, Selkie is trained to perform behaviors that help keepers and veterinarians take care of her and keep her healthy. She holds still for eye exams (and in the event she needs to receive eye drops), injections, radiographs, blood draws and she presents body parts—such as flippers—to animal care staff for examination. She has also been trained to breathe deeply for heart and lung health checks.
Over the centuries, gray seals were hunted commercially. In recent years, some populations have bounced back. Today, they are protected in many areas and hunting is limited in others.
Where Do They Live?
Gray seals are found in the Gulf of Maine, eastern Canada, northern Europe, eastern Europe and Scandinavia. Gray seals breed from eastern Canada to the Baltic Sea. Their Canadian breeding areas range from the Gulf of Saint Lawrence through coastal Nova Scotia, Newfoundland and Labrador.
- Male gray seals can grow nearly ten feet long and weigh between 375 and 880 pounds. Males become sexually mature between four and eight years old. Females are smaller than males, averaging seven to eight feet in length and weighing between 220 and 570 pounds. They become sexually mature between three and five years old.
- A gray seal’s claws allow it to gain traction while maneuvering on ice. Gray seals use their rear flippers to swim.
- Gray seals spend most of their time in the water; they hunt, sleep and even breed in water.
- This species can dive to depths of up to 475 feet.
- They can hold their breath for up to 20 minutes at a time.
- To navigate their surroundings, gray seals rely on their sensitive whiskers.
- Once a year, gray seals molt—or shed their coats—and grow new ones. The new coat is generally darker in color than the molted coat.
- Gray seals have a distinct vocalization from the Zoo’s California sea lions. The sea lions’ vocalizations sound like barks. The seals’ vocalizations sound like deep sneezes.
Thawed frozen-herring, capelin, butterfish, and squid three-to-four times a day. Selkie receives vitamin supplements daily to replace any nutrients lost during the freezing process.
Gray seals live as long as 41 years in zoos. Wild bulls average 25; wild cows average 35.
Harbor Seal (Phoca vitulina)
In fall 2012, the Smithsonian’s National Zoo will receive two harbor seals.
Historically, harbor seals have suffered population drops due to viral diseases similar to distemper, water pollution and habitat loss. Harbor seals are also threatened by humans through hunting and commercial fishing practices. Seals and sea lions in the Unites States are protected under the Marine Mammal Protection Act of 1972.
Where Do They Live?
Harbor seals have the widest distribution of any seal and can be found in both the North Atlantic and Northern Pacific oceans. On the West Coast, their distribution spans from the southern Arctic (Yukon to northern Alaska) down the California coastline. On the East Coast, their range extends from south Greenland to the Hudson Bay and down the coastline to the Carolinas.
- Adult male harbor seals weigh between 120 and 230 pounds and are between five and six feet in length. Adult females are slightly smaller than their male counterparts, weighing between 100 and 190 pounds and averaging between four and five feet in length.
- Depending on where they live, harbor seal coloration can vary greatly from white or light gray with dark spots to dark brownish black with light spots.
- Harbor seals have a higher metabolic rate than other mammals of comparable size. This allows them to generate heat to keep warm. A thick layer of insulating blubber provides thermoregulation as well as a nutrient reserve during fasting periods. During the winter months, the blubber layer can account for up to 30 percent of a harbor seal’s body mass.
- Harbor seals, like other pinnipeds, have adaptations that allow them to dive and conserve oxygen while under water. Harbor seals are able to dive to depths up to 500 feet.
- Although harbor seals are mainly a solitary species, they can be extremely social, especially on land and during breeding season. Due to their naturally solitary lifestyle, they can become very antagonistic toward each other when groups of several hundred congregate on shore.
- Not only do harbor seals use vocalizations to warn other seals about danger, to fend of danger, and to establish hierarchy, but the vocalizations also keep mothers and their pups together.
Thawed frozen-herring, capelin, butterfish and squid three to four times a day.
Harbor seals in the wild can live up to 15 years and between 20 to 30 years or longer in human care.
Gray Wolf (Canis lupus)
The National Zoo exhibits two female gray wolves, Coby and Crystal. They arrived in July 2012 from the Calgary Zoo. Coby was born May 26, 2004, and Crystal was born May 2, 2004. Although Crystal is not Coby’s sibling, they were hand-raised together with Coby’s littermates. Crystal has white fur. Coby has a black and gray coat.
Gray wolves once had one of the largest natural ranges of any terrestrial mammal in the Northern Hemisphere. Human expansion into the western United States placed wolves and humans in conflict from the outset. The wolf population has stabilized as the result of a combination of factors including legal protections, human migration to more urban areas, and land-use changes.
Where Do They Live?
Historically, gray wolves were known to have the greatest natural range of living terrestrial mammals (aside from humans). More recently, their distribution has been restricted to the open tundra and forests in Alaska, Canada and the northern United States.
- Gray wolves are the largest members of the canine family. Females weigh between 50 and 120 pounds, and males weigh between 65 and 175 pounds. They measure four to seven feet from snout to tail tip.
- Depending on habitat location, the coloration of gray wolves can range from white to black with the majority exhibiting light brown or gray coloration.
- The gray wolf is among the most social of carnivores. Their pack usually includes five to eight individuals, but can be as large as 36 individuals. The pack is a family group consisting of an adult pair, which may mate for life, and their offspring of one or more years.
- Gray wolves have a variety of visual, olfactory and auditory means of communicating. Vocalizations include growls, barks and howls. Different individuals have different howls that other wolves can hear at distances of six to seven miles. Howling is a way to keep the pack together, stimulate a hunt and set territorial boundaries.
A mixture of dry canine kibble, meat, fish, bones, frozen prey (mostly rabbits) and vegetables.
In the wild, gray wolves can live between seven and eight years and up to 20 years in human care.
North American Beaver (Castor canadensis)
The Smithsonian's National Zoo has three American beavers. Chipper, Buzz and Willow were born in June of 2000. They weigh between 40 and 55 pounds. Chipper is the lightest in color and smallest in size (approximately 40 pounds). Buzz is the largest at about 55 pounds. Willow is similar in size to Buzz. She is easily identifiable by a notch in her tail.
The Zoo’s beavers are learning behaviors that help animal care staff evaluate their health, including opening their mouths and showing their paws and bellies. American Trail keepers are training the animals to voluntarily sit in a crate (for any transporting they may have to do), get on a scale (for weekly weight measurements), and hold still for injections and blood draws.
North America had between 60 and 400 million beavers when Europeans first arrived on the continent. The fur trade—which peaked in the 19th century—drastically reduced populations. Today, millions of beavers live throughout North America.
Where do they live?
Beavers are found in ponds, lakes, rivers, marshes, streams, and adjacent wetland areas throughout North America.
- Beavers are the largest rodents in North America and the second-largest rodents in the world (after the South American capybara).
- A beaver’s teeth never stop growing. The incisors—the long, dark orange visible teeth—are self-sharpening and can chop down a willow the size of a person’s finger in a single bite. Their lips do not close over the incisors, but are pulled tightly behind them. This is an important adaptation to the aquatic side of their life, which permits them to work underwater without their mouth filling with water.
- The front feet are small, dexterous and well adapted to work on land. Beavers walk on five digits, grasp sticks with their front paws and have claws built for digging.
- Other characteristics include webbed hind feet, large, rudder-like tails that help them steer in water, excellent diving skills, and specially adapted eyes that allow them to see underwater.
- The tail varies in shape from short and broad to long and narrow and is an individual and family trait. In general, it is about two inches thick at the base and about a quarter of an inch thick at the tip. It is practically hairless and covered with black scales. The tail is used as a rudder for swimming, as a balance prop while on land, and as a danger signal when slapped on the water.
Beavers cut trees for construction projects such as dams and lodges. They will repair any breaks or holes in their dwellings. At the National Zoo, keepers provide the beavers with browse to eat and arrange.
Mixed vegetables and fruits, rodent chow and a healthy supply of wood.
Beavers have a lifespan of about 23 years, both in the wild and in human care.
North American River Otter (Lontra canadensis)
The Smithsonian’s National Zoo has one North American river otter named Niko, born at the Lowry Park Zoo in January 1999. Niko is cautious when exploring or doing something new. He was named in honor of Nikolass Tinbergen, one of two European zoologists credited with founding modern ethology (the study of animal behavior). Niko's brother, Konrad, who died in 2015, was named for the second zoologist, Konrad Lorenz.
Husbandry training is an important part of river otter care at the National Zoo. Keepers have trained these animals to hold still for eye exams (and to receive eye drops, if needed) and dental exams. When keepers need to perform an all-over body check, they ask Niko to present other body parts.
These otters' range has been greatly reduced by habitat loss. Otters are very sensitive to environmental pollution.
Where Do They Live?
The North American river otter is native to the United States and Canada. They live both in the water and on land, making their homes in burrows near the water's edge. Despite their name, river otters can thrive in river, lake, swamp or estuary ecosystems.
- These otters propel themselves through the water by using their powerful tails and flexing their long bodies. They have webbed feet, water-repellent fur to keep them dry and warm, and nostrils and ears that close in the water. For underwater swimming they have a third eyelid, or nictitating membrane, that protects the eye while allowing the otters to see underwater.
- Adults are usually two to three feet long and one to two feet tall.
- North American river otters are very active and always on the lookout for food due to their high metabolic rate.
- They can dive as deep as 60 feet and can hold their breath for up to 8 minutes.
- These slick swimmers usually live in mated pairs in the wild. Offspring live with their parents until the adults are ready to breed again.
- River otters patrol the bottoms of the inland waterways where they make their homes for food such as fish, frogs, crayfish, mollusks or other invertebrates.
- They have a variety of vocalizations, ranging from whistles to buzzes, twitters, staccato chuckles, chirps and growls.
A prepared meat diet, mice, carrots, hard-boiled eggs, clams, crayfish, dry kibble, crickets and several types of fish.
River otters live 10 to 15 years in the wild and up to 25 years in human care.
Bald Eagle (Haliaeetus leucocephalus)
The Smithsonian’s National Zoo is home to one bald eagle, a male named Tioga. He came to the National Zoo from the American Eagle Foundation in Dollywood, Pigeon Forge, Tennessee. He was born in 1998 and found injured in the wild as a fledgling near his nest in Pennsylvania. He was unable to fly because he had fractured his left shoulder. It healed out-of-position, and he never regained the ability to fly. Since Tioga cannot fly, he could not be released back into the wild. He arrived at the Zoo in June 2003.
- In 1973, the bald eagle was listed on the U.S. Endangered Species List due to population declines from pesticide use (including DDT), lead poisoning, hunting and habitat loss. A decade earlier it was estimated that only 417 pairs of eagles remained in the United States. The ban of DDT in many states may have greatly helped the eagles recover.
- In 1995, bald eagle populations were healthy enough to merit a downgrade from “endangered” to “threatened” on the Endangered Species List. In 2007, they were officially delisted.
- Though they have been delisted, the bald eagle population in the United States is closely monitored. Both the Bald and Golden Eagle Protection Act and the Migratory Bird Treaty Act protect bald eagles.
Where Do They Live?
Bald eagles live all across North America, but they are always found close to water. They prefer to nest along coastlines, rivers, and other bodies of water ranging from Canada, the Pacific Northwest, the Gulf of Mexico, the Mississippi River and the East Coast of the United States.
- The bodies of mature bald eagles, both males and females, are mostly brown with a distinctive snowy white head, neck, tail and tail coverts (feathers around the base of a quill). They also have pale yellow irises and yellow feet and beaks. Bald eagles range in weight from six to 14 pounds with a wingspan of up to eight-and-a-half feet.
- Females are generally larger than males and have a slightly longer wingspan. Northern birds are usually larger than southern birds.
- They possess sharp, pointed beaks designed for ripping and tearing prey into bite-sized pieces.
- They have powerful legs and feet that are equipped with large talons used for killing their prey.
- Long, wide wings provide them the ability to stay aloft and conserve energy by soaring.
- Keen, full-color vision is their most developed sense and is used for finding prey.
- Bald eagles construct large nests out of sticks twigs, grass and any other materials they may find. Typically, they build these nests in very tall trees or on cliffs. A pair of bald eagles may reuse these nests from year to year.
- Bald eagle hatchlings begin to fly when they are about three months old. They are completely independent from their parents at four months old.
Rats, fish, chicken legs, mice and quail.
Bald eagles can live up to 50 years.
Common Raven (Corvus corax)
The Smithsonian’s National Zoo has four ravens: one breeding pair—Iris (female) and Chogan (male)—and two females that do not have names yet.
Chogan arrived at the national Zoo in October 2011 from the Buffalo Zoo. He was injured as an adult in the wild of Montana, and as a result, cannot fly. Iris arrived at the National Zoo in May 2012 from Chehaw Animal Park in Georgia. She hatched in March 2009. She is fully flighted and was hand-raised to be an education ambassador.
Once controlled, their numbers are now increasing.
Where Do They Live?
The raven has an extremely large range. It can be found in much of North America, Europe, Asia and coastal areas of northern Africa.
- Like other corvids, ravens have strong, large feet and fairly long bills.
- Ravens most closely resemble the common crow; however they soar most similarly to the hawk. Another distinguishing feature is their slender wings and wedge-shaped tail.
- Ravens boast a plume of black feathers, along with black bills and feet.
- Ravens range in size from two to two-and-a-half feet tall, and they can have a wing span of four to seven feet.
- Ravens are highly intelligent animals and can use their beaks to rip objects open, helping them find both food and shelter. They have been known to use tools to obtain food and aide in defending their territories.
- Ravens are very communicative with upwards of 30 different vocalizations. They are known best for their loud, croaking vocalizations.
- Ravens are acrobatic fliers and can catch food and objects mid-air. During breeding season, ravens perform a series of chases, dives and rolls to impress their mates.
- Although ravens do scavenge for food, they also hunt. If prey is too large for a single bird, multiple birds will join forces to bring down their meal. They will also eat eggs and nestlings of other birds, rodents, grains, worms and insects.
Mice, crickets, mealworms, various fruits, a specialized meat-eating bird diet of ground beef, hard boiled eggs and a few different types of commercial dry pellet feed.
In the wild, ravens can live up to between 10 and 15 years. In human care, it is possible these birds could live to between 40 or 50 years of age.
Brown Pelican (Pelecanus occidentalis)
American Trail has two female brown pelicans, Wendy and Tinkerbell. The Smithsonian’s National Zoo acquired these birds from the Suncoast Sunbird Sanctuary in spring 2001. (Located in Indian Shores, Fla., Suncoast is a rehabilitation facility for injured birds.) Both birds have wing injuries that prevent them from being released into the wild.
Although there are many brown pelicans globally, the species was once severely endangered in the United States, primarily due to pesticide poisoning. Since DDT was banned, brown pelican populations have made a full recovery on the East Coast, and other populations show steady improvement. They still face threats including entanglement in abandoned fishing lines, flying into overhead wires, human disturbance of nesting colonies, and reduction of fish stocks by excessive commercial fishing.
Where Do They Live?
- The brown pelican can be found from Virginia south to the mouth of the Amazon River in Brazil, from central California to south-central Chile and the Galapagos Islands, and in Alabama, Louisiana, and Texas along the Gulf Coast.
- The brown pelican is the only species of pelican that lives mostly in a marine habitat. They are most commonly found along coastlines in shallow bays and estuaries. Pelicans will also congregate near convenient food sources such as fishing piers and docks to feed on fish scraps from boats.
- Brown pelicans are the smallest species of pelican. Males and females are similar in plumage and both are three to five feet long and weigh more than seven pounds.
- There is no distinction in markings between the sexes. The head is white with a pale yellow wash on the crown; the long bill is grayish; back, rump, and tail are streaked with gray and dark brown; the breast and belly are a blackish-brown; eyes pale yellow; and legs and feet are black.
- The brown pelican’s most distinguishing feature is a long beak measuring approximately nine inches in length with a hooked tip and large pouch beneath. The pouch is used as a dipnet and holds the catch of fish until the water (as much as three gallons) is squeezed out. The pouch itself can hold three times more fish than the stomach. Once the water has drained, the pelican swallows the fish.
- Adult brown pelicans make very few vocalizations. Occasionally, they will make a low croak.
- Flying over the ocean, brown pelicans can spot a school of small fish from heights of 60 to 70 feet. The pelican then dives into the water, submerging completely or partially and comes up with a mouthful of fish. Air sacs beneath the pelican's skin cushion the impact and help it surface. Brown pelicans are the only species of pelican that hunts with such dramatic plunging dives.
Thread and Pacific herring and capelin. They are also given vitamin supplements based on the amount of fish they eat.
Brown pelicans typically live 25 to 30 years.
Hooded Merganser (Lophodytes cucullatus)
The Smithsonian’s National Zoo has two hooded mergansers: One male, Paulie, and one female, Carmella. They hatched at the Zoo’s Bird House and now live in American Trail’s beaver exhibit.
Habitat destruction and degradation has limited this species’ populations, though they are not listed as endangered or threatened. Their populations fall when they lose nesting cavities to logging, something that can be mitigated by forest management and the building of artificial nest boxes. Water quality changes in many parts of the country due to increased sedimentation and water turbidity make it harder for mergansers to find food. Improving water quality and restoring natural hydrology in wetland areas help the species.
Where Do They Live?
Hooded mergansers breed in southeastern Canada, and spend the winter along the East Coast of the United States and the Gulf Coast. They are occasionally found on the West Coast. Hooded mergansers live in forests (along streams) and in marshes where they can nest in the cavities of trees.
- Hooded mergansers are the smallest North American merganser species. Typically, they are between one and two feet long.
- The male is black and white with tawny brown sides and flanks. Their heads sport a dramatic fanlike crest, featuring a large white spot surrounded by black plumage. Males have bright yellow eyes, duller yellow feet and a black bill.
- Females have a more modest appearance. Their heads are reddish brown with a backward slanted crest that is smaller than that of the males. Their backs are a dusty brown, and their chests and sides are gray. They have dusky brown backs and gray chests and sides. The females have brown eyes, green feet, and their bills are black on top, yellow on the bottom and outlined in orange.
- Males weigh about two pounds and females weigh less than two pounds. Although it is similar in size to the wood duck, the merganser’s body is slenderer and the wings are narrower.
- Hooded mergansers prefer to nest in tree cavities, hollow trees, and even the open tops of tree stumps.
- Hooded mergansers almost always build their nests right next to water, unlike many other species of duck.
Mergansers eat fish, crustaceans and aquatic insects. At the Zoo, these ducks are fed sea duck diet and mealworms.
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