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What happens to ecosystems during major storms? WIND DISLOCATION Powerful winds from hurricanes and tropical storms can blow birds off course and push them hundreds of miles away from their home habitat. Last year, a North Carolina brown pelican was found on the roof of a night club in Halifax, Nova Scotia. The news often covers the appearance of rare species after a major storm. Sometimes younger or weaker birds become separated from their flock and many can take weeks to return home — if they can find the right foods on their way back. During major storms, sea birds and waterfowl are most exposed. Birds are not the only species affected by the winds. Sea mammals can be harmed too. While many can seek shelter in open water or in near shore shelter, some dolphins and manatees have actually been blown ashore during major storms. TREE LOSS In 1992, Hurricane Andrew brought incredible wind velocities onshore and knocked down as many as 80% of the trees on several coastal Louisiana basins, such as the Atchafalaya. Tree loss during Hurricane Katrina in 2005 caused even more extensive damage. Loss of coastal forests and trees can be devastating to dependent wildlife species and migratory species. Many wildlife species have very specialized niches in these forests that are lost to heavy winds. Specific foods can be taken away too. High winds will often strip fruits, seeds and berries from bushes and trees. DUNE AND BEACH LOSS Storm surges, wave action, and winds can cause beach and dune erosion and that can have severe effects of species. Many wildlife species live in ecological niches in the sandy areas and dunes of coastal barrier island. In some cases the storm can cause a beach area to disappear. Sea turtle nests, for example, can be washed out, or a water surge, called a “wash over” can submerge these nests or tern and plover nesting areas. SALTWATER INTRUSION The sustained and powerful winds of a hurricane will cause salty ocean water to pile up and surge onshore. These “storm surges” can be huge. Hurricane Irene’s surges brought water levels that were as much as 8 feet above normal high tide and Katrina pushed a 30 foot high surge onto the coast. In addition to the physical damage this causes, the salt contained in sea water dramatically shifts the delicate balance of freshwater and brackish wetland areas. Creatures and vegetation that are less salt-tolerant will be harmed and many will not survive this influx of sea water. Marsh grasses, crabs, minnows, fish hatchlings, insects, and myriad creatures of freshwater and estuarine environments are harmed. The salt water intrusion in these some of these areas does not drain off very quickly and can even harm or kill off bottomland forests and other coastal trees. FRESHWATER FLOODING The reverse is true too. The heavy rains generated by hurricanes will dump water in coastal area river basins (called watersheds) and this, in turn, can send vast amounts of fresh water surging downstream into coastal bays and estuaries. This upsets the delicate and finely tuned freshwater/salt water balance that can be so vital for the health of these ecosystems. In 1972, Hurricane Agnes sent such massive amounts of freshwater into the Chesapeake Bay. The normally brackish (partially salty) water was fresh for months placing great pressure on the species living there. TURBIDITY Heavy rainfall in upstream areas also washes soil, sediment and many pollutants into coastal and marine environments. After Hurricane Agnes, the turbidly or cloudiness of the water became so severe in the Chesapeake Bay that the native grasses growing on the bottom of Bay died off in huge quantities. These grasses provided critical habitat from crabs, fish spawning and many species. It took the Bay years to recover. Similarly, sediment can wash over coral reefs, blocking needed sunlight and even causing algae to grow. MARINE AND AQUATIC SPECIES When hurricane Andrew hit Louisiana more than 9 million fish were killed offshore. Similarly an assessment of the effect of that same storm on the Everglades Basin in Florida showed that 182 million fish were killed. Hurricane Katrina also had a huge effect on dolphin species. Many dolphins were hurt during the storm and were rescued and underwent rehabilitation.