Bald Eagle Viewing More Likely During the Winter

• Main Author: Cobourn, John; Purdy, Shelly; Segale, Heather M.
• Format: Moving Image (Video)
• Language: English
• Published: University of Nevada, Reno - Department of Teaching and Learning Technologies 2005
• Subjects: Bald eagle > Tahoe; Lake; Region (Calif. and Nev.); Canada; Nev; Tahoe Lake; White Head; Northern Goshawk; Alaska; osprey
• Online Access: http://contentdm.library.unr.edu/cdm/ref/collection/ltresources/id/348

Lake Tahoe Report Segment #153 - "Bald Eagle Viewing More Likely During the Winter" (Air Date: Jan. 23, 2006). Segment 153 - Sighting a bald eagle is a magnificent experience, especially after the bald eagle’s near extinction in the not-so-distant past. The bald eagle population fell to endangered levels of less than 500 pairs in the early 1960s due to hunting, habitat loss and contamination of waterways and food sources by various pollutants and pesticides, most notably DDT. There was a similar drop in eagle populations at Lake Tahoe during the late 1980s, when the two nest sites in the basin were both inactive. There are usually only one or two pairs of bald eagles in the Tahoe Basin during the summer. However, during the winter, bald eagles migrate to Tahoe because it is more temperate than Alaska and Canada. According to wildlife biologist Stewart McMorrow, “as many as 20 eagles have been counted in the Tahoe Basin during the winter months.” Bald eagles live near large bodies of open water, such as lakes, marshes, seacoasts and rivers, where there are plenty of fish to eat and tall trees for nesting and roosting. Bald eagles feed primarily on fish, but also eat small animals, such as ducks, coots, muskrats, turtles, rabbits, and snakes. Occasionally, they also eat dead animals. They are a kind of predator called raptors. They swoop down to seize fish in their powerful, long and sharp talons. They exert approximately 1,000 pounds of pressure per square inch in each foot. They can carry their food off in flight, but can only lift about half their weight. Bald eagles can fly at speeds of about 65 miles per hour in level flight, and up to 150 or 200 miles per hour in a dive. Bald eagles are monogamous and mate for life. A Bald eagle will only select another mate if its faithful companion dies. They build large nests, called eyries, at the top of sturdy, tall trees. The nests become larger as the eagles return to breed and add new nesting materials year after year. Bald eagles make their new nests an average of 2 feet deep and 5 feet wide. Eventually, some nests become 10 feet wide and weigh several tons. When a nest is destroyed by natural causes, it is often rebuilt nearby. Bald eagles line their nests with twigs, soft mosses, grasses and feathers. The female lays one to three eggs each spring, which hatch after about 35 days of incubation. Feathers of newly hatched bald eaglets are light grey, and turn dark brown before they leave the nest in about 12 weeks. When they are 3 or 4 years old, bald eagles have mottled brown and white feathers under their wings and on their heads, tails and breasts. The distinctive white head and tail feathers do not appear until they are about 4 to 5 years old. Their beaks and eyes also turn from dark brown to yellow during this time. Bald eagles are about 29 to 42 inches long, can weigh 7 to 15 pounds, and have a wingspan of 6 to 8 feet. This makes them one of the largest birds in North America. Females are larger than males, but both have white heads and tail feathers and yellow beaks. The bald eagle is our national symbol, so when it became threatened with extinction in the 1960s, people took notice. Strong endangered species and environmental protection laws, as well as active private, state and federal conservation efforts, have brought back the bald eagle population from the edge of extinction in the United States. The use of DDT pesticide is now outlawed in the United States, which has contributed greatly to the return of the bald eagle to America's skies. There are now over 5,000 nesting pairs and 20,000 total birds in the lower 48 states. There are over 35,000 bald eagles in Alaska. There are several other common raptors living at least part of the year in the Lake Tahoe Basin. One of the most common is the osprey, which is somewhat similar in appearance to the bald eagle, having white markings on its head and throat and a dark brown back and tail. It also preys mostly on fish. Most nests that you see in the Tahoe Basin are osprey nests. Sometimes eagles will steal freshly caught fish from the slightly smaller ospreys. Forest hawks, which do not fish for food, include the sharp-shinned hawk, the Cooper’s hawk, and the northern goshawk. Such raptors are called accipiters. Other raptors in the Basin include the merlin, the great horned owl, the western screech owl, the flammulated owl, the northern Pigmy owl, the northern Saw-whet owl, and the rare California spotted owl. Red tail hawks also frequent Tahoe, and peregrine falcons sometimes pass through the region. For more information about the birds of the Tahoe Basin, visit http://www.fs.fed.us/r5/ltbmu/recreation/wildlife/birds.shtml.