Extirpated, immigrated, genetically stratified-first demographic assessment of a recovering bobcat (Lynx rufus) population after a century of extinction

摘要

The bobcat (Lynx rufus) is a widespread mesocarnivore that declined in the USA as immigration and settlement proceeded. It was considered extirpated in Ohio (OH) around 1850, and generally extinct for a century. Listed as state-endangered in 1974, verified reports increased in the 1990s. Population clusters developed in 2 areas of OH, and genetically stratified. The eastern population increased more rapidly, and the southern was part of a multistate population including West Virginia (WV) and Kentucky (KY). To investigate the recovering bobcat's population ecology, the State of OH collected carcasses of bobcats who died mostly from vehicle collision while state-listed. We processed specimens for demographic data, and supplemented the southern sample with western WV and eastern KY harvest data given genetic relatedness. We applied a vertical life table framework interpreting our population cross-section as a recovery period. We estimated age structure, fecundity, and population status of eastern OH bobcats, and compared fecundity between areas. Life-table analyses indicated an eastern OH population hovering around zero growth. Juvenile females contained most reproductive value, and most males died as young adults. Fecundity in eastern OH surpassed that of the multistate population overall where comparable. Fecundity increased through several years of life as bobcats matured. Our results suggest, after a rapid recovery of eastern OH bobcats, population growth slowed as they began to saturate their environment. OH delisted bobcats in 2014 and proposed a harvest season in 2018. With loosening regulation, we recommend more robust sampling for improved population modeling after expansion of the recovered population's range.