The Pollard transect count method was adopted. At each locality a fixed transect, typically of between 1 to 4 km in length, was walked. Butterflies observed either in flight or settled on vegetation within 5m on either side of the observers were recorded. There was no restriction on the recording distance in front of the observers, or on the height at which the butterflies could be recorded. Information recorded included species, abundance, sex (if possible) and the habitat types where each species was seen. The butterfly surveys were undertaken between March and November, which covers the flight period of most local species. The transects were walked between 09:30 and 16:30 on rainless days, when the temperature was generally high enough for butterflies to become active. Other variables recorded included time, weather and cloud cover, as well as the presence of butterfly eggs, larvae or pupae, and special behaviour such as courtship, mating and hill-topping. |
