Do you see the creature in the tree?
Its looking at you.
Now, I am sure you see it.
This is a Black-crowned Night-Heron, Nycticorax nycticorax. A truly awesome bird. Their loud "QUUAARRKK!" drew our attention to them; there were two sitting in trees next to the river. Black-crowned Night-Herons are fairly common throughout North America, although the populations did take quite a hit in the late 1960's due to DDT. Night-herons, as the name suggests, are nocturnal and crepuscular when they feed. They will roost all hunkered down in trees during the day and apparently we had disturbed them.
Black-crowned Night-Herons are opportunistic feeders, meaning, just like some guys I know, they will eat anything that is in front of them. They prefer fish, but will also take small mammals, amphibians, other birds, reptiles, eggs, crayfish, mussels, insects, worms, leeches, carrion, plants and garbage. This feeding behavior can help with survival. If one food source is limited, they can easily switch to another source. Raccoons and oppossums are other opportunistic feeders and everyone knows how prevalent they are!
Night Ravens, another name for these secretive midnight munchers, are bioindicators. (The Greek scientific name Nycticorax means night raven.) Since Black-crowned Night- Herons are high on the food chain, if their populations start to drop, scientists receive a heads-up on contaminations or other pollution problems in their ecosystems.