The Lesser Yellowlegs is a coastal bird, very similar to the Greater Yellowlegs, albeit smaller as one would expect. Telling one apart from the other is difficult, as the size difference may not be apparent if both species are not close by. Both have long, bright yellow legs, with white underparts and mottled gray upperparts, which turn brownish during the non-breeding season. The bill is long and slender, mostly black, although non-breeding adults may show a very small basal portion that’s colored in yellow.
Five species of birds compose the Cinclus genus, all of which have a very unique characteristic: They dive underwater to catch small fish and invertebrates, along with their eggs and larvae. They are most commonly found along river banks and fast flowing streams. Being able to swim underwater, they bear adaptations for this purpose. For instance, their bones are solid to reduce buoyancy, while the feathers are dense and covered in oil that repels water, which has two effects: Maintaining the body dryers, and capturing a small layer of air around its body. The White-capped Dipper in particular is dark gray on the upper side, white on the underside and shows a white cap that goes well with its common name.
The Black-necked Stilt is a wader bird, meaning it walks in shallow waters, looking for small prey to snatch. It does not dive and is not usually seen swimming. The stilt has a streamlined body and extremely long pink legs, allowing it to wade in deeper waters than other, smaller waders found in Costa Rica like the Plovers and Sandpipers. It has a contrasting black and white body. When startled, they usually fly away in a wide circle and return to a similar place they were before.