Injury Determinations for Humpback Whales and Other Cetaceans Reported to NOAA Response Networks in the Hawaiian Islands During 2017

Reports of cetaceans with human-caused injuries in Hawaiian waters are made each year to the Pacific Islands Region Marine Mammal Response Network (PIR-MMRN, coordinated by the NOAA National Marine Fisheries Service (NMFS) Pacific Islands Regional Office) and the Hawaiian Islands Entanglement Response Network (HIERN, coordinated by the NOAA Hawaiian Islands Humpback Whale National Marine Sanctuary). These injury reports largely involve humpback whales that were entangled in fishing gear or marine debris or were struck by or otherwise made contact with a vessel. Bradford and Lyman (2015, 2018) made determinations of injury severity (i.e., serious or non-serious) for cetaceans in Hawaii reported injured by human causes during 2007–2016. Prior to this work, most human-caused injuries reported to PIR-MMRN and HIERN were not accounted for in the mortality and serious injury (M&SI) estimates that are a key component of the Stock Assessment Reports (SARs) for cetaceans in Hawaiian waters. The present paper provides a summary of injury determinations for cetaceans in Hawaii reported injured by human causes during 2017. Injury determinations were made using a nationally standardized process and criteria for distinguishing serious from non-serious injuries (NMFS 2012). During 2017, there were 12 reports of cetaceans with human-caused injuries, including 4 humpback whales involved in vessel collisions, 7 humpback whales entangled in presumed fishing gear or marine debris, and 1 pantropical spotted dolphin of the 4-Islands1 stock entangled in marine debris. The 11 humpback whale vessel collisions and entanglements led to 6.45 serious injuries, and the entangled spotted dolphin was determined to be seriously injured. Estimates of M&SI in the SARs are considered over five-year periods. The 2017 M&SI estimates can thus be compiled and averaged with those from 2013–2016 (Bradford and Lyman 2018) for the relevant 2019 SARs. While accounting for injuries reported to PIR-MMRN and HIERN has improved the stock assessment process for some populations, significantly more effort is needed to report, document, and monitor injured cetaceans in Hawaiian waters, particularly species other than humpback whales.

Bradford AL, Lyman EG. 2019. Injury determinations for humpback whales and other cetaceans reported to NOAA response networks in the Hawaiian Islands during 2017. U.S. Dept. of Commerce, NOAA Technical Memorandum NOAA-TM-NMFS-PIFSC-81, 18 p. https://doi.org/10.25923/7csm-h961. https://doi.org/10.25923/7csm-h961.