The most abundant grebe in the world, the Eared Grebe is a small waterbird with a very thin bill and a bright red eye. In the summer months, golden wisps fan out from their cheeks as they dance and run across the water courting. They breed in colonies in shallow wetlands in western North America and head by the hundreds and thousands to salty inland waters to feast on brine shrimp before heading farther south. In winter, they lose the golden wisps, turning gray and white.
Eared Grebes amass by the thousands at inland salty waters during migration. In the fall (late July through November) they head to either Mono Lake in California or the Great Salt Lake in Utah. In the spring (late January through early April) they tend to congregate at the Salton Sea and the Great Salt Lake, skipping Mono Lake. Here, spotting an Eared Grebe or a few hundred won't be a challenge, the challenge might be in separating them from Horned Grebes; look for the smudgy cheek patch on Eared Grebes and the clean line between the cap and the cheek on Horned Grebes.
In the fall, almost the entire population of Eared Grebes flies to Mono Lake, California, or Great Salt Lake, Utah, to fatten up on brine shrimp and alkali flies before migrating farther south. Here they more than double their weight, and the sizes of their muscles and organs change. The pectoral (chest) muscles shrink to the point of flightlessness and the digestive organs grow significantly. Before departure for the wintering grounds, the process reverses; the digestive organs shrink back to about one-fourth their peak size, and the heart and pectoral muscles grow quickly to allow for flight.
A cycle similar to that of the fall staging areas occurs 3–6 times each year for the Eared Grebe. For perhaps 9–10 months each year the species is flightless; this is the longest flightless period of any bird in the world capable of flight at all.
The Eared Grebe migrates only at night. Because of the length of its stay at fall staging areas, its southward fall migration is the latest of any bird species in North America.
On cold, sunny mornings, the Eared Grebe, like some other grebe species, sunbathes by facing away from the sun and raising its rump, exposing dark underlying skin to light. This behavior may make the bird appear to have a distinctive "high-stern" profile.
Eared Grebes might be the whales of the bird world in one sense. Researchers suggest that they use their large, fleshy tongue much as baleen whales do, crushing prey against the palate to squeeze out the salty water.
The oldest recorded Eared Grebe was at least 8 years, 7 months old when it was found in California in 1998, the same state where it had been banded.