Wildlife Preserves

Lesson 4: Hopper Mountain National Wildlife Refuge Complex

Wildlife

The magnificent California condor came to the brink of extinction in 1985, when only 9 birds remained in the wild. The last free-flying condor was captured in 1987, and successful captive breeding programs at the San Diego and Los Angeles zoos brought the population back to a total of 54 birds by 1992. Two zoo-born chicks were released in the Sespe Condor Sanctuary in 1992, and an additional 31 condors have been released at 3 different sites since then. The first wild laid and incubated egg hatched in April 2002. Condors are North America's largest land bird, with wingspans of up to 9 feet. They are mostly black, with a bare orange or yellow-orange head and neck, a white bill, and several white patches on the wings. They exist chiefly on carrion, as their talons do not have the strength to kill prey. Adulthood comes late, at 5-6 years of age, and usually only one egg is laid on bare rock in a cave or on a cliff ledge. Incubation takes two months, and the parents must feed the chicks for another 12 to 14 months. Such a slow reproduction cycle is one reason the birds nearly disappeared. Habitat destruction and misguided hunting also helped them on their way out of the ecosystem. There is a web-cam available to watch one of the condor feeding stations at http://www.bigsurcalifornia.org/ then click on California Condors, then Condor Cam.

Western snowy plovers are pretty little shorebirds that are becoming so scarce the species is listed as endangered. With a weight less than 2 ounces, this dainty creature has a hard time escaping predator attacks, leaving it especially vulnerable to human habitat interference such as beach construction, dune stabilization projects and off-road vehicular use. Plover nests are simply depressions in the open sand above the tide line, making the clutch of 2-6 eggs easy pickings for larger shorebirds, hawks, and carnivorous mammals or snakes. The fuzzy little chicks can run within hours of hatching, but are unable to fly until about 4 weeks old. The parents signal danger, the chicks crouch in the sand, and the adults try to lure predators away by pretending to be injured, fluttering across the dunes. Plovers eat worms from the wet sand or kelp that has washed on shore, or insects from low-growing plants.

The elephant seal bull has a face only a mother could love, but the cows and pups with their soft brown eyes are endearing. Only the male has the huge flabby "trunk" through which he trumpets with great gusto. This species migrates further than any other mammal, in the world, over 6,000 miles one-way per season. There are a number of elephant seal rookeries along the coast of California, and on several offshore islands. The largest recorded bull measured 18 feet long and weighed over 6,000 pounds. When two bulls bellow and fight for a harem, the cows and pups shuffle for cover or risk being crushed in the melee. Elephant seals are at home in the open sea, can dive over 5,000 feet below the surface, and can stay underwater for more than 80 minutes (even longer than the longest whale sounding.) The seals' size was almost the species' downfall. They were hunted for their blubber, and by the late 1800s, only 100 animals were left. Natural predators include the orca (killer whale), which preys on pups at the water's edge. Today, the elephant seal population has increased to about 130,000. They are still a carefully protected species.

Sea otters are among nature's cutest creatures. They often float on their backs, casually grasping kelp stalks, forming a companionable raft of silvery brown furred animals. They dive for food in the shallow coastal waters, and sometimes use rocks as tools to crack the shells of clams, scallops, or abalones. Sea otters must eat 25 percent of their body weight per day (enough crabs to weigh 10-15 pounds!) to stay warm in the cold ocean water. Their fur is very dense, 600,000 to 1 million hairs per square inch, with the surface hair naturally oiled to keep out water. Otters spend a lot of time grooming to keep their underfur immaculate. If the fur becomes matted, they can die from hypothermia. This lovely pelt led fur hunters to kill hundreds of thousands of otters from Japan down the coast of the United States to Baja Mexico. Fortunately, a small raft of otters, numbering only 300 animals, survived the slaughter, and the species was saved from extinction. Only about 2,300 southern sea otters live along the Big Sur coast, within a range of only 200 miles. They are of course protected by the Endangered Species Act and the Marine Mammal Protection Act.

Gray whales are migrant visitors to the Guadalupe-Nipomo Refuge waters each year, on their way to calving waters in Baja California. Their migration route is almost as long as the elephant seal's - 5,000 miles one way. Gray whales are baleen whales, mottled gray and covered by barnacle clusters on their heads and backs. Their tail flukes are very broad, almost one-fourth their total body length, to provide propulsion for their long journeys. The baleen plates that hang down on either side of their upper jaws act as sieves to filter nearly invisible tiny sea creatures called amphipods from sediment the whales suck up while lying on their sides at the bottom of the sea. In one five-month period of summering near Alaska, a gray whale consumes about 396,000 pounds of amphipods. In winter, the whales eat little while in the calving area. A 16-foot long calf is born to a female once every two years, and the mothers are very protective of their offspring. Adults are up to 50 feet long and may weigh 45 tons, normally living 40-50 years. Predators are humans and killer whales. By the 1930s there were only a few hundred gray whales left in the ocean, and in 1948 the International Convention for the Regulation of Whaling banned all hunting of gray whales except by aboriginal people for use as food only. Gray whale population is now estimated at about 21,000 animals.

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