The outstanding one was by Louise Mair of the University of York and was entitled 'Abundance changes and habitat availability drive species' responses to climate change'. I would normally avoid lectures about climate change like the plague, not because I don't believe it is happening but because all you ever hear is the bleedin' obvious! But there was a lecture on the effects of nitrogen deposition on the Wall Brown during the same session so I stuck it out.
Louise had used data from the various butterfly atlases to look at distribution changes and from the UK Butterfly Monitoring Scheme to look at abundance changes, so if you have ever submitted records for one of the atlases or done a transect you have contributed to her work. She found that butterflies ability to extend their range northwards was related to habitat availability (bleedin' obvious you might say, but wait...) when the source populations were stable or increasing but when the source populations were in decline, as they were in most cases between the late '90's and late '00's, habitat availability was irrelevant. So, to quote the abstract from one of her papers 'This suggests that stable (or positive) abundance trends are a prerequisite for range expansion.' She pointed out that most climate change research focussed on the availability of suitable habitat for species to colonise and ignored the health or otherwise of the source populations. I understand that her papers have a very high citation index and have clearly had an impact within the scientific community but I suspect that her work remains entirely unknown within the conservation sector.
This is important because I think that her work has implications well beyond climate change. No-one can have failed to notice that these days nature reserves are out of favour. Everything is about 'landscape scale conservation' (LSC). Now I don't have a problem with LSC as a concept. Clearly it would be a good thing if you could increase the amount of suitable habitat for species to colonise but my problem is with the apparent attitude that it is the only thing that matters. When LSC was first being promoted, the main justification seemed to be 'we've been managing small nature reserves for x years and still species are declining so we need to do things on a much larger scale'. That would be all well and good if the nature reserves were being well managed. I remember a new Conservation Officer being appointed to a County Wildlife Trust (before everyone had pompous titles!) and saying that that Trusts' reserves were 'the worst managed pieces of land in [that county]'. What's changed? If anything, nature reserve management has got considerably worse in the intervening years. I'm sure you can all come up with numerous examples of mis-management of nature reserves. So what are the implications of Louise Mair's findings in this respect? If you don't manage your nature reserves properly and get strong, stable or increasing populations, you can do whatever you want in the surrounding landscape and species will still not colonise those areas. Bleedin' obvious? Maybe, but if it is, it seems to have by-passed the conservation movement in Britain at the moment.
I hope that Louise will get funding to continue her research (she's welcome to have the data from my recording scheme to analyse) and that she will promote her work to the conservation movement as well as the scientific community. How about an article in British Wildlife Louise?
