2015 Catch Sampling and Estimation in the Federal Groundfish Fisheries off Alaska
February 19, 2015
Federal fisheries conducted in waters off Alaska are some of the largest in the world. In 2013, almost 2.4 million metric tons (t) of fish and shellfish were commercially harvested in waters off Alaska, which was just over half of the total catch in U.S. waters (NMFS 2013a). Many of these fisheries are governed by the Magnuson-Steven Fishery Management and Conservation Act (MSA), which, among other things, requires establishing fishery management plans (FMPs) that are consistent with the MSA and its National Standards. The management of Federal groundfish fisheries off Alaska is governed under FMPs that are specific to the Bering Sea and Aleutian Islands (BSAI) and Gulf of Alaska (GOA) regions (Fig. 1). The catch of FMP species is monitored using landing and production information that is reported by the commercial fishing industry and at-sea information collected from an extensive at-sea observer program. These data sources are integrated into a NMFS application called the Alaska Catch Accounting System (the CAS) and used to produce the total catch estimates referenced in the FMPs.
The primary purpose of the CAS is to provide estimates of total catch for FMP species in the groundfish and halibut fisheries and allow the in-season monitoring of catch against limits as required in the FMPs. We use the term “total catch” to describe the sum of retained and at-sea discarded species and the term “retained catch” to describe quantities of fish not discarded at sea. Species that are targeted in fisheries or have biological characteristics that require them to be protected by conservation and management measures are called groundfish in the FMPs (NPFMC 2013a and 2013b). These species fall under the authority of the MSA National Standard 1 as “in the fishery” and have annual catch limits (ACL) that potentially requires in-season managers to close fisheries when a limit is reached. The FMPs also specify ecosystem components that are composed of fish species that must be avoided by vessels catching groundfish. Specifically, ecosystem components are composed of forage fish (e.g., capelin) and prohibited species (i.e., Pacific salmon (Oncorhynchus spp.), steelhead (O. mykiss), Dolly Varden (Salvelinus malma), Pacific herring (Clupea pallasii), Pacific halibut (Hippoglossus stenolepis), king (Lithodes spp. and Paralithodes spp.) and Tanner (Chionoecetes spp.) crab). Prohibited species often have complicated sector and seasonal catch limits or allocations that require in-season monitoring using the CAS.