Last Update: 12/22/17



Horseshoe Crabs

Horseshoe crabs are a naturally occurring species in the waters of Long Island.  They are a listed internationally as a species of special concern – meaning their numbers are declining.  In Long Island Sound and surrounding waters, they are an important commercial bait species – horseshoe crabs are harvested and sold to be used as bait for eels and whelk, which are then sold to China.  Horseshoe crabs are also harvested elsewhere along the east coast for medical reasons – their blood is important in medical testing of antibiotics.  These crabs are also important ecologically:  their eggs are an important food source to some species of migratory shore birds.

Since the species is so important to the local economy and to regional ecology, scientists are studying why the species is declining.  Recent research suggests that, in Long Island Sound estuaries, beaches are experiencing a lot of erosion leaving them with less sand and with a lot of cobble and rock.  This is the preferred habitat of the Asian shore crab which preys on juvenile horseshoe crabs.  More experimentation needs to be done to confirm this theory, but, even so, habitat loss is a major concern for Manhasset Bay and Long Island Sound.

What you can do:

·         Support local habitat restoration efforts by viewing them as a positive move for the Bay and local economy (sometimes there are volunteer opportunities associated with these restoration efforts)

·         Excessive nitrogen in the ecosystem has been linked to the die-off of coastal habitats:  pay attention to new regulations and research made to address this problem

·         Know where your sewage goes:  the main source of nitrogen to Manhasset Bay is from sewage treatment systems.  If you have a cesspool or septic system, make sure your system is regularly pumped out and properly functioning.  Additionally, as these systems are not designed to remove nitrogen, consider upgrading to a system that does or to connect to sewer when it’s time to get a new system.


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