Supplemental Methods and Figures from Effects of inbreeding on reproductive success in endangered North Atlantic right whales

• Main Authors: Carla A. Crossman, Philip K. Hamilton, Moira W. Brown, Lisa A. Conger, R. Clay George, Katharine A. Jackson, Sonya N. Radvan, Timothy R. Frasier
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: 2024
• Subjects: Ecology not elsewhere classified; Genomics; ddRAD sequencing; North Atlantic right whale; inbreeding depression; inbreeding; conservation; heterozygosity-fitness correlations; Eubalaena glacialis; North Atlantic
• Online Access: https://doi.org/10.6084/m9.figshare.26323599.v1; https://figshare.com/articles/journal_contribution/Supplemental_Methods_and_Figures_from_Effects_of_inbreeding_on_reproductive_success_in_endangered_North_Atlantic_right_whales/26323599

Only approximately 356 North Atlantic right whales ( Eubalaena glacialis ) remain. With extremely low levels of genetic diversity, limited options for mates, and variation in reproductive success across females, there is concern of the potential for genetic limitations of population growth from inbreeding depression. In this study, we quantified reproductive success of female North Atlantic right whales with a modified de-lifing approach using reproductive history information collected over decades of field observations. We used double-digest restriction site-associated digest sequencing to sequence approximately 2% of the genome of 105 female North Atlantic right whales and combined genomic inbreeding estimates with individual fecundity values to assess evidence of inbreeding depression. Inbreeding depression could not explain the variance in reproductive success of females, however we present evidence that inbreeding depression may be affecting the viability of inbred fetuses—potentially lowering the reproductive success of a species as a whole. Combined, these results allay some concerns that genetic factors are impacting species survival as genetic diversity is being retained through selection against inbred fetuses. While still far fewer calves are being born each year than expected, the small role of genetics underlying variance in female fecundity suggests that variance may be explained by external factors that can potentially be mitigated through protection measures designed to reduce serious injury and mortality from human activities.