About Black Coot
They breed in spring. Both birds build a floating nest of stems and leaves in vegetation by lakes or in a marsh. They lay 5-15 grayish-buff eggs, covered in dark brown and black speckles and spots. Both the male and female will incubate the eggs for 21-24 days.
This waterbird is very social in the winter, but beware in the summer during breeding season. During the winter, these birds will gather on inland lakes, or any open water, in groups of up to 1,000 or more birds.
The will dive for food by flattening their feathers to expel the air before plunging down. They propel themselves by the broad lobes on their big, powerful feet. They bounce back to the surface like a cork. As food is harder to find in the winter, they may become quite tame. They will gather to areas where people will feed them and they will eat out of the hands of humans.
During the breeding season they become an entirely different bird. Both the male and the female become territorial, defending their boundaries with aggressive displays that often lead to fights. They will swim at each other with their heads down, tails raised and their wings arched. Some will turn tail and run but some will not and they stay to fight. They will slash at each other with their sharp claws. They will also attack other birds who are much bigger than themselves.
Black Coots take every opportunity to set up new colonies, sometimes on reserviors, or flooded gravel and sand pits.