A new study has found that the sensitivity and recovery of UK butterfly populations to extreme drought is affected by the overall area and degree of fragmentation of key habitat types in the landscape.
The analysis, published this week in the scientific journal Ecography, used data on the Ringlet butterfly collected from 79 UK Butterfly Monitoring Scheme sites between 1990 and 1999, a period which spanned a severe drought event in 1995.
The study was led by Dr Tom Oliver from the NERC Centre for Ecology & Hydrology (CEH) in collaboration with colleagues from CEH and the charity Butterfly Conservation.
Lead author Dr Tom Oliver from the NERC Centre for Ecology & Hydrology said, "Most ecological climate change studies focus on species' responses to gradual temperature rise, but it may be that extreme weather will actually have the greatest impact on our wildlife. We have provided the first evidence that species responses to extreme events may be affected by the habitat structure in the wider countryside; for example in the total area and fragmentation (i.e. isolation) of woodland patches."
The UK has suffered from a number of severe droughts over the last few decades (e.g. 1976, 1995). Under global warming, the frequency of such summer droughts is expected to increase. The intense summer drought in 1995 led to marked declines in insect species associated with cooler and wetter microclimates and scientists are interested in how to make species populations more resilient, i.e. more resistant to and more able to recover from these extreme climate events.
The Ringlet Aphantopus hyperantus is a grass-feeding butterfly commonly found close to woodland edges and known to be susceptible to drought effects. The researchers found that, following the 1995 drought, Ringlet populations not only crashed most severely in drier regions but, additionally, the habitat structure in the wider countryside around sites inf
|Contact: Barnaby Smith|
Centre for Ecology & Hydrology