University of New England marine biologist James Sulikowski, Ph.D., has placed himself in the middle of a contentious debate between conservationists and the commericial fishing industry over the health of the spiny dogfish stock.
Sulikowski, assistant professor, Department of Marine Sciences, has been awarded a $237,000 grant from the NOAA Saltonstall-Kennedy Grant Program to use satellite tags to examine the behavior of spiny dogfish in the Northwest Atlantic. The research will try to determine the habitat, depth and movement patterns of the spiny dogfish to better understand the inconsistencies in data collected by federal agencies and the commercial fishing industry.
The status of the spiny dogfish, Squalus acanthias, stock in the northwest Atlantic Ocean has become a volatile issue. Distributed from Labrador to Florida, this species was once considered to be the most abundant shark throughout this geographic range.
However, with the decline of traditional groundfish resources in the last 15 years, an increase in directed fishing for spiny dogfish resulted in a nearly ten-fold increase in U.S. landings from 1987-1996, reducing the stock below survival threshold levels.
The Debate Based on this reported decline, conservation groups are suggesting the species should be protected while commercial fishing interests say that spiny dogfish are abundant in northeastern U.S. waters.
The National Marine Fisheries Service and the Mid Atlantic Fishery Management Council, agencies charged with managing the spiny dogfish, are thus in the middle of a volatile issue and rely on Northeast Fishery Science Center (NEFSC) bottom trawl survey data to estimate spawning stock biomass and thus base management decisions from those results, among other factors.
A management plan consisting of a 4-million pound annual quota and reduced possession limits for vessels fishing in federal waters was established in 2000. Despite these measures, the spiny dogfish stock is not expected to rebound before 2020; however, recent NEFSC survey data suggest a three-fold increase in spawning stock biomass occurred between 2005-2007, an increase considered biologically unrealistic by many.
In addition, data supplied by commercial fishermen and scientists suggest that anomalies within the recent NEFSC bottom trawl survey exist, such as a skewed 4:1 male to female ratio, which suggest, to some, a flawed estimate of the stock status.
Sulikowski's Research Sulikowski proposes to build upon his recent success using advanced tagging technology to test the hypothesis that the horizontal and vertical behavioral patterns of spiny dogfish preclude the species from being effectively captured by NEFSC otter trawl surveys thus resulting in data that do not accurately reflect trends in spiny dogfish abundance.
Ultimately, anomalies could account for the substantially larger spiny dogfish biomass observed by the fishing industry and field biologists.