Photographer James Kusz hit the grebe jackpot with this video of a Horned Grebe in breeding plumage (video above), followed by a photo of a Horned Grebe surrounded by two Eared Grebes, all in breeding plumage, below. I’ve seen both species before but never together. As far as the sources I looked at reveal, the two species don’t hybridize.
The Eared Grebes are said to be the most common grebes in existence, but they have some quite uncommon features. The Cornell bird lab says
- 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.