Monster Seminar JAM - Sea Turtle Bycatch in NW Atlantic Waters: The Truth Behind the Magic Number
Kimberly T. Murray, Resource Evaluation and Assessment Division, Protected Species Branch, Northeast Fisheries Science Center
AbstractIn this presentation I review an approach to estimating bycatch of threatened and endangered sea turtles in Northwest Atlantic waters and describe how bycatch estimates are used in fisheries management. Computing robust bycatch estimates can be difficult due to the rare nature of sea turtle bycatch events and low sampling levels. Datasets typically have excess zeros in the data, and there is low power to detect significant effects when analyzing bycatch rates. Using a case study of loggerhead (Caretta caretta) sea turtle bycatch in the U.S. Mid-Atlantic sink gillnet fishery (Murray 2009), this presentation reviews some of these analytical concerns and approaches to dealing with uncertainty. In this study I developed a Generalized Additive Model to describe bycatch rates of loggerheads, and then applied this model to commercial fishing effort to identify times and areas where conservation efforts should be focused. Finally, I describe how bycatch estimates are typically used in Endangered Species Act (ESA) Section 7 consultations and efforts by colleagues at the NEFSC to put sea turtle bycatch into a broader population context.
Date and Time:
February 11, 2010,
11:00 am - 12:00 pm