climate & ecosystems
Listening to NYTimes Science Podcast, about the problems facing the grizzly population on some nature reserves in the US. The main problem, according to the scientist interviewed, is changing climate that is affecting bark beetles, affecting something or other which eventually affects the grizzlies (wasn’t listening closely).
So this is an interesting problem with climate change that I hadn’t really thought of previously. As long as climate change happens gradually, we can be fairly confident of nature’s ability to adapt: as the overall climate warms, species will tend to move north to relatively colder climates, to maintain roughly their climate and ecosystems. This should happen across the board, and indeed we are seeing this in the migration patterns and presence of new species in areas where they’d not before been present.
The problem is, however, that human use of land (cities, towns, roads, highways, farming) has penned in natural areas (often set aside by government decree to protect zones of nature). So they tend to be surrounded by blocks to movement.
This means that, on a large scale, as the climate warms (which, whether or not you believe it has anything to do with human activities, is not in doubt), the normal adaptive response of sepcies - moving north - may well be blocked off. So so nature reserves may end up losing significant species, who are not able to migrate anywhere else.
