Grebes

Grebes are a distinct and fascinating group of small to medium-large aquatic diving birds that belong to the order Podicipediformes. These birds are found worldwide, from freshwater lakes to marine habitats during migration and winter, with grebes even including some flightless species. The grebe family, Podicipedidae, comprises 22 species across six genera, known for their specialized lobed toes suited for swimming, diving, and somewhat awkward movement on land. Often monogamous, grebes are celebrated for their elaborate courtship dances and floating nests where they lay several eggs. Their conservation status is concerning with a third of species facing various threats such as habitat loss, invasive species, and hunting, which have already led to the extinction of three grebe species. Grebes bear a unique appearance with dense, waterproof plumage that can be ornate during the breeding season but more subdued in winter. They have the ability to regulate their buoyancy and, uniquely, are known to ingest their feathers, potentially aiding in digestion and protection against parasites. Although they resemble loons and coots and were historically associated with them, grebes are actually more closely related to flamingos, as determined by anatomical, molecular, and paleontological studies. Their fossil record suggests they likely originated in the Southern Hemisphere, with an incomplete record that indicates a sudden appearance 23–25 million years ago. Today, grebes are found worldwide except in the Arctic and extremely arid environments. Some species are resident while others migrate between freshwater breeding sites and coastal marine environments for winter. Their diet ranges from small aquatic invertebrates to mid-depth fish, depending on the species and bill shape. Grebes have a complex reproductive behavior, including courtship rituals like synchronized swimming and dances with aquatic vegetation. After these displays, they construct nests on the water, and both parents partake in rearing the young, who often ride on their parents' backs for safety. Grebes also play host to a variety of parasites, both internal and external, including an array of worms and lice. Preserving grebe populations requires attention to threats such as habitat destruction, climate change, and invasive species. Without action, more species risk becoming extinct, similar to the unfortunate fate of lake-endemic relatives like the Alaotra grebe, the Atitlán grebe, and the Colombian grebe.