Extremely Low Genetic Diversity in the Endangered Hawaiian Monk Seal (Monachus schauinslandi)

• Published in: Journal of Heredity
• Main Authors: Schultz, Jennifer K., Baker, Jason D., Toonen, Robert J., Bowen, Brian W.
• Format: Text
• Language: English
• Published: Oxford University Press 2009
• Subjects: Original Articles; Antarctic; Antarc*
• Online Access: http://jhered.oxfordjournals.org/cgi/content/short/100/1/25; https://doi.org/10.1093/jhered/esn077

Hunted to near extinction in the late 19th century, the endangered and endemic Hawaiian monk seal ( Monachus schauinslandi ) exhibits low variation at all molecular markers tested to date. Here we confirm extreme paucity of genetic diversity, finding polymorphisms at only 8 of 154 microsatellite loci tested (143 novel species-specific loci, 10 loci from Antarctic seals, and 1 previously characterized locus). This screening revealed unprecedentedly low levels of allelic diversity and heterozygosity ( A = 1.1, H e = 0.026). Subsequent analyses of 2409 Hawaiian monk seals at the 8 polymorphic loci provide evidence for a bottleneck ( P = 0.002), but simulations indicate low genetic diversity ( H e < 0.09) prior to recorded human influence. There is little indication of contemporary inbreeding (F IS = 0.018) or population structure ( K = 1 population). Minimal genetic variation did not prevent partial recovery by the late 1950s and may not be driving the current population decline to ∼1200 seals. Nonetheless, genotyping nearly every individual living during the past 25 years sets a new benchmark for low genetic diversity in an endangered species.