Coastal Forests

Coastal forests—whether upland forests, bottomland hardwoods, or mangrove swamps—often sustain substantial damage during hurricanes. Desiccation and salt stress causes some of the damage, but the most notable destruction comes from storm-generated winds, which can snap, uproot, and completely defoliate trees. In 1992, the mangrove forests of Florida were particularly hard hit by Hurricane Andrew; for example, 80–95% of the mangroves in Everglades National Park were damaged by trunk snapping and uprooting (Smith et al. 1994).

Analysis of specific habitat loss following Hurricanes Katrina and Rita (2005) suggests that swamps dominated by bald cypress (Taxodium distichum) and water tupelo (Nyssa aquatica) were much less severely impacted than other ecosystem types, such as bottomland hardwood forests. Some forests directly in the path of Hurricane Katrina suffered as much as 80% wind throw, while cypress–tupelo swamps were left relatively intact. As such, investigators suggest that bald cypress–tupelo swamps are essential for coastal wetland restoration strategies. However, cypress–tupelo swamps are not immune to the effects of hurricanes and tropical storms, and are particularly sensitive to saltwater inundation (Jackson 2006).

Although various tree species exhibit different responses to hurricane-force winds, one trait is common: larger trees are more heavily damaged than smaller trees. During Hurricane Hugo (1989), smaller trees were less damaged than larger ones in the coastal forests of South Carolina (Gresham et al. 1991). Similarly, in mangrove forests, hurricanes usually inflict the greatest damage on the largest trees (Smith et al. 1994), and large trees in tropical ecosystems have been observed to be uprooted more frequently than smaller trees (Lugo et al. 1983). As a result, some investigators have suggested that hurricanes are a major selective force in coastal forest structure (Gresham et al. 1991).

Last updated: July 11, 2019