Thursday, November 19, 2015

#WhatsInTheTrap

By David Prescott, Save The Bay South County Coastkeeper

It is not often that you get the chance to really see who lives at the bottom of the Bay. Most times we are swimming along the shore, boating over the surface or fishing off the beach. However, just a few feet below the surface, we discover a whole new world of fish, crabs and shellfish.

Three summers ago, Save The Bay partnered with Rhode Island Department of Environmental Management (Division of Fish and Wildlife) and the University of Rhode Island on a study to determine the abundance and distribution of blue crabs within Rhode Island. My focus area was in the lower Pawcatuck River and Little Narragansett Bay in Westerly. The purpose of the project was to analyze the effects of climate change of the geographic expansion of the range of blue crabs. In other words, as our local waters get warmer, are we seeing a northward shift of southern species (such as blue crabs)?

Save The Bay deployed  blue crab traps and checked them frequently throughout the season. While blue crabs were the species of interest to RIDEM and URI, I was equally interested in what other species of crabs and fish made Little Narragansett Bay their home.

We definitely counted large numbers of blue crabs over the past several summers. They seem to prefer the warmer waters of the tidal river where we found the greatest numbers.  However, in addition to blue crabs, we have counted various numbers of other species of crustaceans (lobsters, green crabs, rock crabs, and spider crabs) as well as fish (oyster toadfish, summer flounder, tautog, cunner, scup, rock gunnel, northern pipefish and black sea bass). Many of these animals loved the protection of the cage and used it as a refuge to hide from other predators.

While the study by RIDEM and URI concluded in 2014, Save The Bay has continued to monitor these traps for changes in species composition and abundance. This past summer was the summer of the scup. Large numbers of good sized scup (eight to ten inches) found their way into the traps on a regular basis. In addition, we also caught our first predominantly freshwater species – catfish. It is always interesting to discover what we find as we pull up these traps to the surface of the Bay.


To follow our adventures as we check our traps next season, you can follow me on Twitter @coastkeeperRI or follow the hashtag #WhatsInTheTrap