Some female white-necked jacobin hummingbirds have male-like plumage and mimic male appearance — but not male behavior, researchers report
The bird pelvis is an example of terminal addition, a biological mechanism in which ancestral features continue to appear in an animal until late in its development.
Osprey have several adaptations that help it hunt fish, including closable nostrils to keep out water during dives. The kind of fish they hunt depends on what region the bird is living in.
American Dippers have a black cap, brownish-black back, and white underparts. They are also known as “water ouzels” or “water dippers” because they spend most of their time swimming underwater
Lava gulls are omnivores like most Larus gulls, generally scavenging or stealing from nests and from fishers, but will also catch fish, small crustaceans, and newly hatched lizards, iguanas, and turtles.
The Swallow-tailed gull (Creagus furcatus) is a nocturnal foraging seabird that breeds mostly in the Galapagos Islands; a few pairs nest on Malpelo Island off Colombia.
The glaucous-winged gull is rarely found far from the ocean, and is a familiar sight from the western coast of Alaska to the coast of Washington.
The northwestern crow can be told apart from the American crow (Corvus brachyrhynchos) by its body size, which is about 10% smaller, and its smaller feet