A new international study published in Nature Ecology and Evolution, led by researchers from Bielefeld University, reveals the genetic impact of hunting on northern elephant seals. This species was on the verge of extinction due to hunting at the beginning of the 20th century, with genetic analyses suggesting that the population was reduced to fewer than 25 animals. The severe population decline resulted in lasting genetic effects in the present population, increasing the risk of inbreeding and threatening its survival. Despite this, the population has recovered to around 225,000 individuals, and the study examines how this near-extinction event impacted the species’ genetic diversity and health.
By combining genetic data, health records, modeling of population sizes, and genetic simulations, the researchers found that the severe population decline led to the loss of many beneficial and harmful genes from the northern elephant seal’s gene pool. This loss of genetic diversity may impair the species’ adaptability and ability to cope with future environmental changes, such as those caused by climate change, changes to their habitat, or disease outbreaks. The closely related southern elephant seal, which did not experience such a drastic decline, did not exhibit the same loss of genetic diversity.
Despite the potential for inbreeding due to the loss of genetic diversity, the researchers found no signs of health problems related to inbreeding in the northern elephant seals. They believe that the severe population decline may have eliminated many harmful mutations, resulting in surprisingly robust health traits in the population. This research highlights the importance of understanding a species’ unique population history in shaping its genetic diversity, offering important insights for species conservation and ecosystem management.
The study emphasizes the importance of considering a species’ history when planning conservation strategies, as each species responds differently to threats. Individualized approaches are essential for effective conservation and management of species and ecosystems. The research provides valuable information for understanding how genetic impact from hunting and other threats can shape a species’ genetic diversity and health, ultimately contributing to the overall conservation and preservation efforts for the northern elephant seals and other species at risk.