Genetic rescue could benefit more at-risk species

Examples of successful genetic rescue include the greater prairie chicken (above), write the researchers. (Credit: Getty Images)

Genetic rescue is a critical conservation strategy that goes unaddressed in the recovery plans of at-risk species in the United States, say researchers.

During a recent review of the US Fish and Wildlife Service’s recovery plans for more than 200 endangered and threatened vertebrate species in the United States, researchers made an interesting discovery. They found that two-thirds of these species could benefit from a gene-boosting diversity strategy known as genetic rescue. Surprisingly, just three of these plans to support species recovery currently use this approach.

Genetic rescue is an increase in population size caused by the movement of new genetic material from one population to another. This can happen through either human-assisted intervention or natural migration. As a conservation tool, this strategy can increase the genetic diversity of small, isolated populations and help them recover from inbreeding.

“These small, isolated populations are becoming more frequent, fragmented, and in trouble,” says Sarah Fitzpatrick, an associate professor in the department of integrative biology at Michigan State University and a faculty member at the W.K. Kellogg Biological Station (KBS). “They might benefit from some human-assisted migration to help infuse deteriorating populations with more genetic variation, which can help them respond to changes in the environment as well.”

Translocating, or the act of moving individuals from one place to another, is a common practice that has most often been used outside the context of genetic rescue.

“This is pretty common in fish management,” says Cinnamon Mittan-Moreau, a postdoctoral fellow based at KBS. “Managers have been moving animals and plants around for more than a century, just not with the intention of increasing genetic variation.”

The good news is that, in many cases, the logistics of carrying out these translocations have already been overcome, and so the time is ripe for more attempts at genetic rescue. Despite this, however, this strategy continues to be left out of species recovery plans.

“We found that over two-thirds of the 222 species we evaluated would be good candidates for consideration of genetic rescue,” says Fitzpatrick. “And yet, we found only three examples of implementation of genetic rescue. As genomic resources become available for more species, we hope to see increased incorporation of genetic information in recovery planning, including informed translocation actions for the purpose of genetic rescue.”

“There’s a lot of opportunity for this to help, but we don’t see it very often,” says Mittan-Moreau. “No one had done this full review to see if this could be considered more often for endangered species plans.”

The paper appears in the Journal of Heredity.

Source: Michigan State University