An Analysis of Marine Mammal Self-Reports and Observer Reports from 1996-2014

Abstract:

Over the past two decades commercial fishing vessel owners have been reporting their interactions with marine mammals in accordance with Section 118 of the Marine Mammal Protection Act. The objective of this study is to analyze marine mammal fisheries interactions data from fishermen self-reports and observer reports. We analyzed self-reports from 1996 - 2014 and Pacific Islands observer data from 2001 - 2014, and Northeast observer data from 1996 - 2014. We identify trends in the national marine mammal mortality/injury (M/I) self-report dataset; identify presence of complementary reports between self-reports and observer reports; and determine the compliance rate of self-reports and observer reports. The results of the self-report analysis indicate that the Greater Atlantic Region (GAR) receives the most M/I reports of the five National Marine Fisheries Service (NMFS) regional offices. The rate of animals reported as killed is three times higher than the rate for animals injured. Dolphins and porpoises are the most frequently reported species and gillnets are the most frequently reported gear type. This study will provide fisheries managers a greater understanding of the effectiveness of the requirement for fishermen to report moralities and injuries of marine mammals incidentally taken during commercial fishing operations. Refinements to the Marine Mammal Authorization Program (MMAP) reporting form will provide more accurate estimates of the M/I rate of marine mammals in each region and will help address the challenges with collecting self-reported incidental take data. Furthermore, the results can be used by managers to determine if self-reporting is informative and should be continued, with form improvements made to increase accuracy, or if the corresponding observer reports serve as sufficient data by themselves.