[Image description: A map of the coastline of New Jersey with Barnegat Bay highlighted in red. End description.]
Just about every person in New Jersey has a story about Hurricane Sandy. My family was lucky; I could tell you an uneventful tale about wandering around on my unexpected day off from school. Others weren’t so lucky, and went weeks without power or lost their homes. But if you asked the critters living off the coast of Barnegat Bay, they might not have much to tell you about the historic storm.
A study headed by Rutgers University’s Gary Taghon found that eight months after Hurricane Sandy, communities of sea slugs, clams, and marine worms were largely unaffected by the storm. Sure, some species of crabs became more common, and a particular species of marine worm became less common, and the nitrogen concentration in the sediment was lower than usual. Nonetheless, this is not the usual effect of a hurricane on seafloor communities. How could a storm that wreaked havoc on the coast (costing $70 billion in damages) leave a bay almost entirely unscathed?
Typically, a hurricane will affect seafloor communities through large amounts of rainfall. The rainfall, being comprised of freshwater, will alter the seawater’s composition and lower its overall salinity. If organisms that live in the area cannot tolerate a lower salinity, they die. The rainfall may also alter the composition of the seawater in such a way that oxygen is removed from its deepest parts, suffocating anything that lives there. Despite its incredible proximity to the origin of the storm, this was not observed in Barnegat Bay during or after Hurricane Sandy.
The storm’s apparent lack of effect on seawater salinity and oxygen concentration may be due to its structure. Most estuaries receive a steady stream of freshwater from rivers. Barnegat Bay, in comparison, does not receive nearly as much freshwater. During the storm, this may have spared its inhabitants from the harm that a sudden influx of freshwater can cause to marine organisms. This study is more comprehensive than the average study on the effect of hurricanes on the seafloor and its sediments. The data was collected as a part of a larger overall study on the Barnegat Bay. One major difficulty in studying the effects of hurricanes on the seafloor is having an accurate picture of the before when the after is readily apparent. Thankfully, data had been collected 3.5 months prior to the hurricane that was used to evaluate the effects eight months after the hurricane. While eight months does not give a clear picture of the immediate effect of the hurricane on the Barnegat Bay, it does demonstrate that there were very relatively little long-lasting effects on the bay and its inhabitants. It really goes to show you how complicated and varied the effects of storms can be. With some luck, more studies like this could be possible, and hurricanes better understood!
Thoughts of an Aspiring Biologist 