Fire on St. Vincent National Wildlife Refuge
Fire is a natural part of the ecosystems in North America. Here on St. Vincent National Wildlife Refuge, fire is ignited in two different ways. The first way is unplanned fires ignited by lightning. These unplanned fires are called wildfires. The second way is planned fires ignited by the refuge fire staff called prescribed fires.
Before St. Vincent Island was altered with roads, lightning would ignite a fire that could burn throughout the islands various habitats. Now when lightning starts a fire, the refuge fire staff decides where to stop the wildfire. We use tactics that minimize damage to the hydrology of the island. These tactics may include using water, building control lines or using a controlled fire called a back fire against the wildfire.
Since the island has been changed by human activity, planned fires called prescribed fires or controlled burns are ignited by fire staff to mimic the lightning fires. Mimicking the lightning fires with prescribed fires achieves the same results as the naturally occurring wildfires. Fire reduces the amount of live and dead leaves from flammable fire-dependent plants, which reduces the potential damage of a wildfire.
Diversity of Habitat
Fire opens up the ground cover to bare mineral soil, so that the plant seeds can have space to germinate. Fire promotes plant diversity in the habitat, which offers a range of food sources for the animals and birds that live on or migrate through St. Vincent National Wildlife Refuge.
Gopher tortoises, one of the many animals living on St. Vincent Island, rely on fire to keep their habitat suitable. Without fire, the woody plants and saw palmetto grow very tall and thick. Little sunlight can reach the ground. The herbaceous plants that are the primary food source for the gopher tortoises do not grow in the shade. Fire keeps the woody plants including saw palmetto short and sparse, so that the herbaceous plants continue to flourish for the gopher tortoises to eat.
Marsh birds, like the sea side sparrow, prefer that marsh grasses are open and free of dead leaves. The sea side sparrow keeps their nests in the more open marsh and walks around on the ground to eat seeds, insects and marine invertebrates. When the marsh is too thick, the sparrows do not nest. Fire keeps the marsh open and cleaned up of dead leaves from the marsh grasses. To keep the grasses open like the sea side sparrow prefers, the fire management staff burns the marshes frequently, approximately every other year.
St. Vincent and St. Marks National Wildlife Refuges share the same fire staff. All but one of the fire staff is located at St. Marks National Wildlife Refuge http://www.fws.gov/saintmarks/fire.html. The fire staff maintains the fire ecology of both refuges and assist nationwide with wildfires and prescribed fires.