REDUCING SEA TURTLE DAMAGE TO CRAB POTS USING A LOW-PROFILE POT DESIGN IN CORE SOUND, NORTH CAROLINA
The blue crab (Callinectes sapidus) supports North Carolina's most valuable commercial fishery;
the value of hard blue crabs landed in 2000 was over $30 million dollars. This lucrative fishery
may be adversely affected by loggerhead sea turtles (Caretta caretta), which are listed as
threatened under the Endangered Species Act of 1973. Crabbers in Core Sound, North Carolina,
report that sea turtle damage to crab pots has become an increasingly serious issue. Turtles
damage crab pots by overturning them while trying to get the bait, tearing up the bottoms and
sides of the pots; this damage results in higher gear replacement costs and losses in crab catch.
Experimental fishing was conducted to test for differences in crab catch and pot damage using
three types of crab pots: low-profile, square mesh, and hexagonal mesh. The hexagonal mesh
pot is the most common pot type used by crabbers in Core Sound, and the low-profile pot was
designed to reduce the sea turtles' ability to overturn the pots. The number and size of all crabs
caught in the experimental pots were recorded. An analysis of variance (ANDVA) was used to
analyze the relationship between number of crabs caught per pot and the effect of pot type,
location, date, the interaction of date and location, and the interaction of pot type and location.
Tukey-Kramer multiple comparison tests were used to determine significant differences among
treatments. There was no significant difference in crab catch between the low-profile and the
square mesh pots at any of the three experimental fishing locations. There was a significant
difference in catch between the low-profile and hexagonal mesh pots at one location. The lowprofile
pots sustained considerably less damage than both the square mesh and hexagonal mesh
pot types. In interviews with 19 Core and Pamlico Sound crabbers, crabbers estimated that 62%
of all crab pot damage, and 37% of lost crab catch, is due to sea turtle damage. The low-profile
crab pot has the potential to improve this situation by allowing crabbers to maintain crab catch
with a reduction in gear replacement costs.
Advisor:Crowder, Larry; Schlesinger, William H.
School Location:USA - North Carolina
Source Type:Master's Thesis
Keywords:blue crab callinectes sapidus loggerhead sea turtle caretta core sound n c pots
Date of Publication:01/01/2002