Improved monitoring can protect genetic diversity

Amphibians – like this tree frog – are a group that is judged to be particularly sensitive to climate change. Photo: Joachim Mergeay

Every living creature differs from other creatures by small differences in its genome. When the environment changes and becomes unfavorable for populations of species, this genetic variation may allow them to adapt to the new conditions, rather than becoming extinct or having to migrate to other habitats. Genetic diversity is one of the keys to the survival of species. In 2022, the United Nations International Convention on Biological Diversity (CBD) adopted stricter guidelines for the protection of the genetic diversity found in wild species.

Global warming is already putting pressure on many species in Europe, especially those with populations at the climate limits of their ranges. The ability of species to withstand extreme heat or drought, as well as new species colonizing their environment, is therefore crucial for survival.

A new study published in Nature Ecology & Evolution has examined the monitoring of genetic diversity in 38 European countries with a focus on amphibians, birds, large carnivores and forest trees.  
 

Linda Laikre
Photo: Sören Andersson

“In general, monitoring genetic diversity is lagging behind other biodiversity monitoring. Now, however, interest in genetic diversity is beginning to increase as the realisation of the central role this part of biodiversity plays in the impact of climate change on animal and plant populations increases. The amount and type of genetic variation, i.e. variation at the DNA level, can be crucial for whether a population can adapt to climate change or not," says Linda Laikre, co-author of the study and professor of population genetics at Stockholm University.

Sweden at the forefront of monitoring genetic diversity

The results of the study show that monitoring efforts vary markedly between countries and even organism groups. Large carnivores are the group with the greatest focus, while there are very few programs for amphibians – a group that is considered to be particularly sensitive to climate change.

“Sweden is at the forefront when it comes to monitoring genetic diversity, even though most of the species that are now in focus are fish and marine organisms, which were not included in the current study," says Linda Laikre.

The Swedish Agency for Marine and Water Management has, together with Linda Laikre´s research team and researchers at the University of Gothenburg, developed indicators for genetic variation that they have used on salmon, trout and char – species that are all expected to be affected by climate change. Moose have also been mapped with genetic indicators in collaboration with the Swedish Environmental Protection Agency.

In Sweden, work with proxy indicators that are not based on DNA data but population information from, for example, the Swedish Red List work has also been started by Linda Laikre and Henrik Thurfjell at the Swedish University of Agricultural Sciences (SLU), who are also co-authors of the study. In this work, genetic indicators for amphibians have been used.
 

Henrik Thurfjell
Photo: Johan Samuelsson

"In Sweden, we have come a relatively long way when it comes to monitoring genetic variation. Therefore, we have the opportunity to contribute knowledge in this area to other European countries that have not come as far," says Henrik Thurfjell, environmental monitoring and assessment specialist at SLU Swedish Species Information Centre.

In the study, the researchers, led by Peter B. Pearman at the University of the Basque Country, also developed a tool to identify geographical areas where genetic surveillance should be prioritised. European programmes should be adapted to cover full environmental gradients and all sensitive regions with high biodiversity.

Article in Nature Ecology & Evolution: Monitoring of species' genetic diversity in Europe varies greatly and overlooks potential climate change impacts

Article from November 2023 related to genetic surveillance in Sweden with new indicators:
New indicators for monitoring genetic diversity applied to alpine brown trout populations using whole genome sequence data