Horned grebes look like small ducks with short, pointed bills. They are 31 to 38 cm long and weigh 300 to 570 g. Breeding adults have a reddish neck, breast, and flanks. They have black heads, and dark throats and backs. They also have orange or golden plumes of feathers on the sides of their heads that look a little like horns. In winter, horned grebes are much duller. They have white cheeks, throat and breast, and a dark crown, nape and back.
Horned grebes are found in the Nearctic and Palearctic regions. They breed from Alaska and northern Canada south through the Canadian prairie provinces to Washington, Montana, South Dakota, and Wisconsin. Populations winter along the Pacific coast from Alaska to Mexico, along the Altantic coast from Nova Scotia to the gulf coast, and on large inland lakes such as the great lakes. They also breed and winter in Eurasia. (Bull and Farrand Jr, 1988; Farrand, 1988a; Farrand, 1988b)
During the breeding season, horned grebes live on freshwater lakes that have some open water and some marsh vegetation. They may also nest in marshes, small sloughs, ponds, and occasionally on rivers. Horned grebes spend the winters in coastal saltwater habitats such as protected bays and exposed shores, and occasionally on large freshwater lakes. (Farrand, 1988b; Kaufman, 1996)
Horned grebes begin breeding when they are 1 year old, and usually raise one brood per year. Breeding pairs form in the winter or spring, and may breed together for more than one year. Like other grebes, horned grebes have complex courtship rituals. Both the male and female may perform these displays, and many displays are performed together. For example, the male and female run on top of the water together with their “horn” feathers raised, then dive together, and then run along the water together again with pieces of plant in their bills. These ceremonies are one way that members of a pair communicate with each other. (Kaufman, 1996)
Horned grebes begin breeding when they are 1 year old, and usually raise one brood per year. They breed between mid-May and early October. The male and female both build the nest, which is located in shallow water among vegetation. The nest is made of floating wet plant material, and is attached to standing vegetation.
The female lays 3 to 8 (usually 5 to 7) eggs at a rate of approximately one every other day. The eggs are whitish to buff when they are laid, but they quickly become stained red and brown from the nest material. Both parents incubate the eggs for 23 to 24 days. The precocial chicks are able to swim and dive immediately after hatching, but are often seen riding on their parent's back for the first week after they hatch. The parents brood the chicks for about 9 days after hatching, and feed them for up to 14 days. Chicks become independent at 20 to 25 days old, but cannot fly until they are 41 to 50 days old. (Bull and Farrand Jr, 1988; Collins, 1981; Kaufman, 1996; Ransom, 1981; Stedman, 2000)
Both adults build the nest and incubate the eggs. After the chicks have hatched, horned grebe parents carry them on their backs often for the first 10 days. They also feed the chicks for 10 to 14 days after hatching. (Stedman, 2000)
The oldest known wild horned grebes lived at least five years and two months.
Horned grebes are excellent swimmers and divers. During dives they may stay underwater for up to three minutes and travel 150-200 meters. They are graceful on the water, but very awkward on land. Their legs are set so far back on their bodies that they are hardly able to walk.
Like other grebes, P. auritus must run along the surface of the water in order to take-off. Horned grebes fly quickly with rapid wingbeats. Their feet and neck are outstretched during flight and their head tilted downward.
Horned grebes are migratory. They spend the breeding season on inland lakes and move to the coast during the winter. They migrate alone and at night.
During the breeding season, horned grebe home ranges typically range from 330 to 30,000 square meters. (Stedman, 2000)
Horned grebes use many different physical displays and calls to communicate with each other. Most calls that horned grebes use are to attract and keep their mate or to defend their territory. A breeding pair may call together in duet. They are mostly silent during the winter. (Stedman, 2000)
Horned grebes eat aquatic arthropods in the summer and fish and crustaceans in the winter. They may also occasionally eat leeches, tadpoles, salamanders, and some plant material. Horned grebes capture their prey by diving underwater. They swallow small prey underwater, but bring large items to the surface to eat.
Like most other grebes, horned grebes swallow many feathers. This probably helps them digest fish bones and other sharp objects.
Adult horned grebes do not have many predators. Incubating adults are vulnerable while on the nest, and may be killed by mink or other predators.
Horned grebes affect the populations of the animals that they eat. They also compete with some fish species for aquatic invertebrate prey. (Stedman, 2000)
Horned grebes feed on small fish, some of which may be economically important species.
Horned grebes have no known affect on humans.
Populations of horned grebes appear to have declined in recent decades. Loss of wetland habitat is a threat to horned grebe populations. Oil spills and pesticide accumulation in their aquatic habitats also hurt horned grebe populations. Other threats to horned grebes include accidentally eating plastics and lead, and becoming tangled in fishing nets. (Kaufman, 1996)
Kari Kirschbaum (author, editor), Animal Diversity Web.
Bradley Handford (author), University of Alberta, Cindy Paszkowski (editor), University of Alberta.
Bull, J., J. Farrand Jr. 1988. The Audubon Society Field Guide To North American Birds--Eastern Region. New York: Alfred A. Knopf.
Collins, H. 1981. Harper & Row's Complete Guide To North American Wildlife--Eastern Edition. New York: Harper & Row Publishers.
Farrand, J. 1988a. Eastern Birds--An Audubon Handbook. New York: McGraw--Hill Book Company.
Farrand, J. 1988b. Western Birds--An Audubon Handbook. New York: McGraw--Hill Book Company.
Godfrey, W. 1986. The Birds of Canada--Revised Edition. Ottawa: National Museums of Canada.
Kaufman, K. 1996. Lives of North American Birds. Boston: Houghton Mifflin Company.
Ransom, J. 1981. Harper & Row's Complete Field Guide To North American Wildlife--Western Edition. New York: Harper & Row Publishers.
Stedman, S. 2000. Horned grebe (Podiceps auritus). Pp. 1-28 in A Poole, F Gill, eds. The Birds of North America, Vol. 505. Philadelphia, PA: The Birds of North America, Inc.