During this warm spell has anyone been seeing many butterflies? It would appear that sightings in the UK in 2011 dropped by almost a quarter compared with the previous year, with several of our more common species affected including Small Tortoishell. See http://www.wildlifeextra.com/go/news/butterfly-survey-2011.html#cr
One thing these stories often forget to mention, all else being equal of course (like the habitat remaining connected and in good condition!), is that insect numbers naturally fluctuate wildly from year to year according to weather conditions. Such declines and recoveries are completely normal for any species where one female can produce hundreds of offspring in one generation when conditions are good again!
Having said that, a long series of cold wet summers may be too much for certain ‘warmth-loving’ species to cope with, and their range and distribution will contract or shift accordingly as they die out where the climate no longer suits. But the power of insect populations to recover quickly when conditions are favourable remains enormous in comparison with birds and mammals that can raise only a few young each year.
Ralph and Dave






















