There are isolated populations of the endangered butterfly, Pyrgus sidae, on the Iberian Peninsula. The mark-release-recapture method was used to study the population parameters, the use of resources and the spatial distribution of a population in the centre of Spain. The estimated number of males and females within the population were similar and did not differ significantly from a ratio of 1 : 1. Total population size was estimated to be 569 ± 83 individuals. Potentilla recta is the principal adult nectar source and larval food plant, and its abundance is correlated with the number of marked and recaptured butterflies. The average total distance moved between capture and recapture was significantly greater for males than females, but the average daily distances moved were similar for both sexes. The spatial distribution of the movements of males and females was of a uniform type and lacked a predominant flight direction, which is typical of sedentary species. Continuing the traditional land use (cattle grazing or hay mowing) of the habitat of the species keeps the habitat open, which is necessary if the butterfly is to survive at this locality. These management practices favour P. recta, which would otherwise succumb to competition from invasive shrubs. Taking into account the habitat requirements of this species, it is important to conserve the mosaic of meadows already present in the area.
Interest in insects as conservation foci and as tools in broader conservation assessment has accelerated markedly in recent years, but the diversity and complexity of insect life demands a more focussed and structured approach to \"biodiversity\" and inventory studies than has commonly occurred. Strategies for insect conservation are reviewed, together with the variety of uses for insects as ecological tools in broader monitoring of environmental quality. Principles fur selecting optimal focal groups are discussed, and the importance of developing standard protocols to sample and interpret insect assemblages emphasised. The global values and relevance of the pioneering lessons in insect conservation developed in Europe are summarised.