Each year we have a change in the diving birds. It starts late fall.
Double-crested Cormorants come down to winter in the south. They don’t seem to care if it’s a fresh water marsh or along the shore.
The numbers of Anhinga will drop about the same time. Being a true tropical bird most will drift even further south.
Since some Anhinga stay year round the two species will commingle at times. Usually the Anhinga pushes Cormorants to other locations unless they are really outnumbered.