Since I didn’t get the clue, from reading the sign or reading her facial expression, she resorted to an all out squawking scream. Perhaps I deserved that.
Among birds, the anhinga is the best fresh-water diver. It goes down quietly and hardly makes a ripple. It finds its food in the water. It spears fish under water with its strong bill. It eats insects, frog eggs, fish and even small alligators. If an object is too large to be swallowed at once the bird spears it on his beak. Then she comes to the surface and flips it off, catches it and lines it up for swallowing.
It spreads its wings out, because it needs to dry its feathers. Most water birds have oil glands on their backs, near their tails, and can spread the oil over their feathers to make them waterproof. But the anhinga cannot oil its feathers.