A COMPARATIVE ANALYSIS OF THE STATUS OF THE U.S. MARINE MAMMAL STOCK ASSESSMENT PROGRAM

Abstract

The Marine Mammal Protection Act (MMPA) includes a multi-step process for reducing national marine mammal bycatch. This process requires the National Marine Fisheries Service (NMFS) to publish annual marine mammal Stock Assessment Reports (SARs), which include best estimates of each stock’s abundance, population trend, maximum rate of increase, potential biological removal (PBR), and ‘annual human-caused mortality and serious injury’. On the basis of these estimates, NMFS determines ‘strategic’ stocks which are most at risk from bycatch. According to the MMPA, a stock should be considered strategic if is: a) Threatened or Endangered under the ESA, or decreasing in abundance and likely to be listed, or b) classified as depleted under the MMPA, or c) experiencing direct human-caused mortality and serious injury at a level which exceeds its PBR. If strategic stocks interact with commercial fisheries that have significant levels of marine mammal bycatch, the agency is required to establish Take Reduction Teams (TRTs), which craft Take Reduction Plans (TRPs). TRPs include measures to reduce the fishery-related mortality of a particular strategic stock, given that the current level of annual human-caused mortality and serious injury exceeds the stock’s PBR. Therefore, without a TRT, the strategic stocks interacting with fisheries that cause either frequent or occasional mortality will continue to remain imperiled because nothing is being done to reduce the unsustainable level of stock mortality. Because NMFS’ status determinations are data-dependent, deficient and/or imprecise stock data hinders the agency’s ability to appropriately determine strategic status. This project assessed the current state of the U.S. marine mammal stock assessment program, with regard to data quality and MMPA compliance, relative to previous assessments by NMFS (2004) and the GAO (2008). The results of this project indicate that previously-identified gaps in stock information and MMPA compliance persist in the 2013 stock assessment reports.