This week’s Bird of the Week, compliments of the Weminuche Audubon Society and Audubon Rockies, is the eared grebe.
Grebes are old. Like loons, evidence dates them way back, evolutionarily speaking. Though they have been genetically proven to share closer ties with flamingos, true grebes can be found in the fossil record at 23 million to 25 million years ago, placing them as emerging in the Northern Hemisphere in the early Miocene period. They have lobed toes, as opposed to webbed feet (more traditional for waterfowl sp.), allowing them to dive deep in the water as an escape mechanism, as opposed to flying. Their legs are found way back on their bodies, ensuring athleticism in the water, but rendering them less adept on land. To this point, they typically build nests on floating rafts comprised of reeds or other emergent vegetation, sometimes anchoring them to shorelines.
Eared grebes are smaller-bodied, not too dissimilar from pied-billed grebes in size. They overlap in range with another similar looking cousin, the horned grebe. Breeding adults don a fashionable array of golden yellow feathers across their cheek, contrasting their bright red eyes, darker charcoal necks and chestnut flanks. Nonbreeding and immature birds offer more sooty intergrades of light brown, rufous and white on their flanks. Courtship displays are regal, with prospective mates moving past one another with necks pointed to the sky, emanating primordial ooo-eek calls and oftentimes nearly “running” across the surface of the water in efforts to impress. Pairs develop monogamous relations for the breeding season only.
Known to migrate later in the fall than the majority of fellow waterfowl (and only at night), the eared grebe spends much of the year sedentary on inland freshwater bodies, gleaning crustaceans and insects.
However, one notable exception occurs during migration: nearly all members of this species make a pit stop at either the Great Salt Lake (Utah) or Mono Lake (California) from late summer to November, where they will gorge themselves on brine shrimp, effectively putting their energy into first organ development (upon arrival) and later pectoral muscle (upon departure) for flight to Mexico for winter. Like other birds that rely on clean water bodies, habitat protection is of utmost importance for species survival.
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