Phenology

Since the late 18 th Century, the timing of biological events has been enthusiastically recorded. With increasing evidence for human-induced global climate change, phenology has taken on greater importance as an indicator of species response to the changing environment.

A number of studies from across Northern Europe and Northern America have demonstrated a clear relationship between the timing of regularly occurring natural events and weather. These studies cover a range of taxonomic groups, showing earlier nesting in birds, advanced arrival of migrant birds and insects, earlier flowering and leafing of trees.

To find out more about what butterfly transect data tells us about phenology and other aspects of butterfly flight periods see the following publications:

Brakefield, P.M. (1987) Geographical variability in, and temperature effects on, the phenology of Maniola jurtina (Lepidoptera, Satyridae) in England and Wales. Ecological Entomology, 12, 139-148.

Pollard, E. (1991) Changes in the flight period of the Hedge Brown butterfly Pyronia tithonus during range expansion. Journal of Animal Ecology, 60, 737-748.

Pollard, E. & Greatorex-Davies, J.N. (1997) Flight-periods of the Small Heath butterfly, Coenonympha pamphilus (Linnaeus) (Lepidoptera: Nymphalidae, Satyrinae) on chalk downs and in woodland in southern England. Entomologist's Gazette, 48, 3-7.

Sparks, T.H. & Yates, T.J. (1997) The effect of spring temperature on the appearance dates of British butterflies 1883-1993. Ecography, 20, 368-374.

Roy, D.B. & Sparks, T.H. (2000) Phenology of British butterflies and climate change. Global Change Biology, 6, 407-416.