Genetic diversity, structure, and effective population size of an endangered, endemic hoary bat, 'ōpe'ape'a, across the Hawaiian Islands

PeerJ. 2023 Jan 25:11:e14365. doi: 10.7717/peerj.14365. eCollection 2023.

Abstract

Island bat species are disproportionately at risk of extinction, and Hawai'i's only native terrestrial land mammal, the Hawaiian hoary bat (Lasiurus semotus) locally known as 'ōpe'ape'a, is no exception. To effectively manage this bat species with an archipelago-wide distribution, it is important to determine the population size on each island and connectivity between islands. We used 18 nuclear microsatellite loci and one mitochondrial gene from 339 individuals collected from 1988-2020 to evaluate genetic diversity, population structure and estimate effective population size on the Islands of Hawai'i, Maui, O'ahu, and Kaua'i. Genetic differentiation occurred between Hawai'i and Maui, both of which were differentiated from O'ahu and Kaua'i. The population on Maui presents the greatest per-island genetic diversity, consistent with their hypothesized status as the original founding population. A signature of isolation by distance was detected between islands, with contemporary migration analyses indicating limited gene flow in recent generations, and male-biased sex dispersal within Maui. Historical and long-term estimates of genetic effective population sizes were generally larger than contemporary estimates, although estimates of contemporary genetic effective population size lacked upper bounds in confidence intervals for Hawai'i and Kaua'i. Contemporary genetic effective population sizes were smaller on O'ahu and Maui. We also detected evidence of past bottlenecks on all islands with the exception of Hawai'i. Our study provides population-level estimates for the genetic diversity and geographic structure of 'ōpe'ape'a, that could be used by agencies tasked with wildlife conservation in Hawai'i.

Keywords: Bats; Endangered species; Hawaiian hoary bat; Hawaiʻi; Island bat conservation; Lasiurus; Microsatellites; Mitochondrial DNA; Population genetics.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Animals
  • Chiroptera* / genetics
  • Genes, Mitochondrial
  • Genetic Variation
  • Hawaii
  • Islands
  • Male
  • Microsatellite Repeats
  • Population Density

Grants and funding

External funding was provided by Kawailoa Wind, LLC to the U.S. Geological Survey Pacific Island Ecosystems Research Center (Agreement: 17WSTAAZB005651), through support by the Hawaiʻi Department of Land and Natural Resources Endangered Species Recovery Committee. Work was supported by the U.S. Geological Survey Pacific Island Ecosystems Research Center and Hawaiʻi Cooperative Studies Unit at the University of Hawaiʻi Hilo. There was no additional external funding received for this study. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.