Scenes of a relocation in South Africa: Here, an entire herd of rhinos is flown by helicopter to a new habitat. © greenrenaissance.co.za
Slowing or stopping species extinction: In a perspective article, Prof. Dr Bernhard Hausdorf discusses conflicts between species conservation objectives and the measures needed to achieve them. In order to make species conservation more effective, he calls for informed trade-offs between different species conservation measures. It must also be considered whether conserving habitats is more efficient than conservation measures in favour of individual species.
Biodiversity on earth is decreasing. However, species conservation has only limited resources at its disposal. For this reason, the measures in which resources are invested must be well evaluated. In a recent article, Bernhard Hausdorf, Head of the Mollusc Section at the LIB Hamburg site, discusses perspectives for species conservation and points out several issues where trade-offs need to be sought in order to conserve species more effectively.
On the one hand, there are often calls for the conservation of populations that are barely viable due to low population size and genetic diversity. On the other hand, scientists propose to increase the genetic diversity of geographically fragmented populations threatened by inbreeding by transporting individuals. “Sometimes, it is not considered whether these are highly differentiated population groups, “nascent species”, and whether they would be able to survive without such costly measures”, Hausdorf counters.
In his opinion, three objectives should be considered in conservation: A maximum number of species and differentiated population groups should be conserved and their viability under current environmental conditions should be taken into account. Finally, the evolvability of species, which ensures long-term survival under changing environmental conditions, must also be guaranteed.
“Unfortunately, this also requires trade-offs: We have to trade off the number of units to be conserved within species against their population size and genetic diversity,” Hausdorf summarises. In addition, he says, it is also necessary to find a trade-off between optimising the fitness of populations under current environmental conditions and increasing variability and thus maladaptation in order to genetically prepare populations for upcoming changes in environmental conditions.
The use of available funds for increasing habitat area and connectivity can be more sustainable and cost-efficient than assisted migration between populations of a few species. Therefore, he urges, “If we are aiming for ambitious goals – such as conserving half of the habitats on land and in the sea – we have to focus on this goal and should not invest too many resources in protecting individual species.”
Bernhard Hausdorf’s holistic model of species conservation appeared in a perspective article in the journal “Biological Conservation“.