 Mangrove coverage is limited elsewhere, with the largest areas in the Indian River Lagoon on the east coast, and the Caloosahatchee River, Pine Island Sound and Charlotte Harbor estuaries and Tampa Bay on the west coast.Mangroves are tropical plants, killed by freezing temperatures.These trees can range about halfway up the coast of the Florida peninsula due to mild winter climate and the moderating effect of the warm waters of the Gulf of Mexico on the west coast and the Gulf Stream and Atlantic Ocean on the east coast.