Government targets for protected area management: will threatened butterflies benefit?
The UK Government has set targets for biodiversity conservation in England based on several indicators, including the status of protected areas [e.g. Sites of Special Scientific Interest (SSSIs)]. Specifically, the Government aims to achieve favourable condition [defined by Common Standards Monitoring (CSM)] on 95% by area of SSSIs by 2010. SSSIs are important for threatened butterflies and management to achieve favourable condition will play a key role in determining future population levels of these high-profile insects. Because only notified features of SSSIs are considered within CSM, we investigated the level of notification for three threatened butterflies. We found that these species were notified at only 15–33% of SSSIs where they occurred; though most site managers did manage for them under broader site conservation objectives. We investigated the relationship between SSSI condition status and population trend for eight butterfly species of conservation concern to assess the benefit to butterflies of sites attaining favourable condition status. The majority (80%) of population trends on SSSIs in favourable condition were positive, suggesting an overall beneficial impact of SSSI management. However, four of the eight species maintained lower populations at favourable condition SSSIs than at sites in one of the unfavourable condition categories. We suggest that current condition assessment based chiefly on notified vegetation communities lacks the sensitivity to identify the complex habitat conditions for these (mosaic) species. As butterflies are good indictors for a wide range of invertebrates, many species requiring fine-scale habitat heterogeneity may be at risk from the Government’s target.