Bird Lore: Eared Grebe

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The Eared Grebe is a bird of the Northern Hemisphere, found in western North America, Europe and Asia. There are no large winter gatherings of this species on Puget Sound. It can be found almost anywhere along the Sound in ones and twos, but protected salt bays such as Quartermaster Harbor at Vashon Island and Deer Lagoon on Whidbey Island offer appropriate habitat. The Everett sewage lagoons near Langus Riverfront Park have also hosted this species. A single bird will sometimes be found in the marsh or along the Edmonds waterfront, among the much more common Horned Grebes. One has been seen a number of times this winter from the jetty at Brackett’s Landing North.

For nesting, the Eared Grebe favors prairie lakes and ponds with extensive marshy borders. It is opportunistic so it will quickly occupy new or temporary habitats. In winter it can be found on freshwater or alkaline lakes and saltwater bays. We see very few Eared Grebes in winter in Western Washington because in fall almost the entire population flies to Mono Lake and Great Salt Lake to fatten up on brine shrimp before migrating further south. This grebe migrates at night.

The Eared Grebe will more than double its weight when feeding on brine shrimp. Its chest muscles will shrink to the point of flightlessness and the digestive organs grow significantly. Before continuing on to the wintering grounds, which are mostly along the West Coast, the southern border, and Mexico, the digestive organs will shrink and the chest and heart muscles will grow quickly to permit flight. The Eared Grebe has the longest period of flightlessness — 9-10 months — of any bird in the world that is capable of flight.

Besides eating brine shrimp when in migration, the Eared Grebe feeds on insects such as aquatic beetles, dragonfly larvae, and flies. It also forages on crustaceans, mollusks, tadpoles, and sometimes small fish. It forages by diving and swimming underwater, propelled by its feet.

Courtship displays can be complex. A pair will swim side by side while turning their heads and calling loudly. They will also face each other, rearing up out of the water, and turning their heads from side to side. The most exciting display is when a pair will appear to stand and then rush across the water’s surface side by side. This species is gregarious and nests in large colonies from Eastern Washington through the prairies potholes.

Both sexes build the nest, which is a floating platform of weeds that is anchored to standing vegetation. Both sexes incubate the three to five eggs for about three weeks. The young leave the nest after the last egg hatches. They are tended and fed by both adults. The young birds will ride on their parents’ backs when small. They may be independent about three weeks after hatching. Age at first flight is not known.

The Eared Grebe often appears to sit high on the water. On cold, sunny mornings, it will sunbathe by turning away from the sun and raising its rump, exposing its dark skin to the light. This gives the bird its distinctive high-stern profile.

The Eared Grebe is the most abundant grebe in the world. Outside of North America, its common name is Black-necked Grebe. The oldest known Eared Grebe was at least eight years and seven months of age when it was captured in California in 1998, the same state in which it had been banded. The collective noun for any species of grebe is “water dance.”

Eared Grebe populations have been stable over the last 50 years. The estimate of the global breeding population is 2.7 million. Thus, it is a species of low conservation concern. It does, however, remain vulnerable to loss of habitat as wetlands are drained. Its heavy dependence on the brine shrimp of Mono Lake, Great Salt Lake, and the Salton Sea adds to its vulnerability.

A large flock of Eared Grebes was recorded vocalizing on a prairie pothole one June: https://www.xeno-canto.org/110082.

— By Carol Riddell

Carol Riddell manages the bird education displays, on behalf of Pilchuck Audubon Society and Edmonds Parks & Recreation, at the Olympic Beach Visitor Station.

2 Replies to “Bird Lore: Eared Grebe”

  1. Cute little creature. I always enjoy your bird articles,Carol. I’ve seen them feeding at Mono Lake. Brine shrimp are disappearing so that will be a problem for the grebes. Dor

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  2. I’m glad that you continue to enjoy the columns, Dorothy. And how nice that you were able to see one of the Mono Lake gatherings. I have been to Mono Lake but not when the grebes were there to feed on the brine shrimp.

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