Date of Award

Fall 12-15-2014

Document Type

Thesis

Degree Name

Bachelor of Science (BS)

Department

Marine Science

College

College of Science

First Advisor

Daniel C. Abel

Abstract/Description

As a result of a long-term longline study conducted by Coastal Carolina University, data on the population structure of sharks in Winyah Bay, SC have been recorded since 2002. The data are collected from late spring to fall each year. Two separate data sets, from 2002 to 2006 and from 2012 to 2014, were analyzed for catch per unit effort (CPUE), catch composition, sex ratios, and average precaudallengths (PCL) for males and females. The average CPUE for the 2002-2006 data set was 2.68 with a standard deviation of 0.73 while the average for the most recent data set was 3.20 with a standard deviation of 2.45. The sandbar shark Carcharhinus plumbeus was found to be the most common species in both sets, and the Atlantic sharpnose shark Rhizoprionodon terraenovae was the only other species to be in the top four most frequently caught species for both 2002 to 2006 and 2012 to 2014. In these species, sex ratios and average PCLs were similar between the two sets of data. Gear selectivity and bait play a role in affecting all of these factors. While these can be standardized, understanding the environmental factors that affect the population structure is more difficult. However, doing both of these is important to successfully managing the elasmobranch populations both in the Atlantic and around the globe. The definite extent of their global decline is unknown, but there will be consequences in the ecosystem if their populations are allowed to continue to plummet. Surveys, like the ones conducted by Coastal Carolina University, can help assess the health of elasmobranch populations which will ultimately lead to better conservation.

Download

Included in

Oceanography Commons

Share

COinS