SC/69A/NH/06  

Document Number

SC/69A/NH/06

Full Title

North Atlantic right whale status update

Author

Daniel Linden, Allison Henry, Danielle Cholewiak

Authors Summary

The North Atlantic right whale population continues to decline, with a median total abundance during 2021 estimated at 340 individuals (credible interval 333-347). The model results continue to show a diverging sex ratio with an estimate of only 143 (137-149) females in the population during 2021. A total of 37 mortalities were observed from 2016-2020, with entanglements and vessel strikes each accounting for 11 of the mortalities. One perinate calf was found dead, presumably from natural causes. The cause of death for the remaining 14 cases was undetermined. Since the start of 2021, 4 mortalities have been observed, all in US waters: 1 calf and 1 adult died from vessel interactions, 1 adult from chronic entanglement, and 1 perinate from maternal abandonment. A recent random forest model applied to live injured whales found that current assessment methods may underestimate risk for injury cases lacking details or long-term observations (Carretta and Henry 2022). Based on the abundance model (Pace et al. 2017, 2021) an estimated 136 (121,195) NARW died during 2016-2020 which was more than 3 times the number of observed deaths.

Publisher

IWC

Keywords

Publication Year

2023