Such loss of genetic diversity can threaten the survival of reintroduced populations.

The main risks are reduced adaptability (particularly problematic under environmental change), increased susceptibility to disease, and inbreeding.

For example, various populations of Alpine ibex are experiencing increased outbreaks of disease, such as such as infectious keratoconjunctivitis (“chamois blindness”). In the worst case, a large part of the population dies after infection. We have shown that ibex with greater genetic diversity at specific gene loci are more resistant.

Bearded vultures in the reintroduced Alpine population have feather defects that make them unable to fly. We are currently investigating at WSL whether inbreeding is also the cause here.