The endemic koloa, looks similar to the female mallard, but smaller at around 16 to 22 inches. Male and females look alike with dark bills, dark sides and cinnamon colored tail. One way to spot a koloa is by their teal colored patch of wing feathers. Unlike mallards, koloa mostly live in mountain streams. This species was nearly hunted to extinction before being protected and reintroduced back into the wild. It’s greatest threat is through hybridization with introduced mallards.