Just a bunch of FWIW's
I think February would be too cold for alligators to be moving about. My dad drives a tugboat, and has for about 30 years. He sees them every day (like coworkers, he says) in the warm months, both during the day, sunning, and at night when he shines his spotlight and it hits their eyes. He told me that he never sees them moving during the winter months, that he has very rarely seen them sunning on the warmest winter days, but it's too cold for them to eat or really move. He said that they just now (april, may) starting to come out and get active. He is in Southern Alabama.
I live on the Mississippi Gulf Coast less than a mile from the bay. I like to walk over to the bay where I fish, and watch the alligators. It is possible that alligators could "swamp" an area, I would think, especially if it was a dock where people threw scraps/fish guts, or just liked to feed the gators. When I was little and would go with my dad to his work, the alligators would pop up everywhere because the deckhands threw scraps to them daily
(which I strongly oppose! Never feed alligators, y'all!) There were lots of them... Especially if it was nearing dusk, because they like to get active/feed then.
Also, for the record, I've never personally caught an alligator gar in salt/brackish water, but I've seen the remains from where other fishermen (or fisherladies
) have caught them in the bayou/bays. I would guess if alligators can live in this brackish water, the gar can, too.
Also, as another person said, alligators can't feed in winter because of belly rot.
Obviously, this is all just FWIW/my experience. I've always liked and had a healthy fear/respect of alligators, growing up on the coast. They were fascinating to me when I was little! They're a dime a dozen down here, it seems. Off topic, but a strange thing my dad told me about alligators- the temperature of their nest determines the sex of their offspring. Weird
ETA: I edited this post because apparently I misunderstood an earlier post. sorry!