Good point. Read one report about some fish that normally migrated out of a Bay before winter, but the extreme cold December in Florida may have messed up their migration patterns. They ended up stuck in the shallow Bay and died in mass from the cold exposure. This was the Coldest December in recorded history for Southern Florida, Eastern Florida and Tampa Bay. After this next Arctic blast we could see almost the entire US coastline much colder then normal. Just took a look at that map again and only South Carolina and North Carolina currently have coastal waters at normal temps. Everything else is already colder except Alaska and Hawaii.
Locally, the nuke power plant at Oyster Creek in Ocean County caused a few fish kills over the years. Seems that they waited until late fall to do some servicing and the warmed cooling water had kept some summer species which normally would have migrated by then. When it was shut down they died.
Of course the eviro-whackos tried to claim that it was radiation poisoning...