BEHAVIORAL AND DISTRIBUTIONAL EFFECTS OF HUNTING DISTURBANCE ON WATERBIRDS IN EUROPE - IMPLICATIONS FOR REFUGE DESIGN

1. Based on studies of effects of hunting disturbance on local waterbi rd distribution and abundance, freedom from such disturbance is conclu ded to be an important part of waterbird management on nature conserva tion areas. Measures to mitigate the effects of disturbance from hunti ng are reviewed. These include complete removal of hunting in refuges, as well as spatial and temporal regulation of hunting activity in res erve areas outwith hunting-free refuges. 2. Disturbance-free refuge de sign should take account of the ecological requirements of all species using a site and the functional units required to meet all daily acti vities, especially primary feeding and roosting areas used by waterbir ds. Refuge size and shape must ensure birds are free from the effects of external disturbance. The most effective are of regular shape, maxi mum practicable size, and as a minimum should have a diameter of three times the escape flight distance of the most sensitive species presen t. 3. Zoning in non-refuge areas can increase local bird numbers by re stricting disturbance to regular predictable stimuli to which habituat ion is more likely. Mobile hunting activity close to roosting and/or f eeding areas is more disturbing than hunting from fixed points or wher e birds are shot moving between such areas. Intermittent hunting is no t an effective means of minimizing disturbance, but where implemented rest periods between hunting events should be considered in weeks rath er than days. 4. Most studies of mitigation techniques to minimize hun ting disturbance have been descriptive and retrospective. Manipulative studies testing specific hypotheses are essential to create a sound s cientific base for management. 5. Management of hunting activity shoul d take place within a broader management planning framework that ident ifies ideal and operational objectives in the management of the site, including feedback monitoring to determine the effectiveness of manage ment prescriptions. 6. We recommend that local site management plannin g should be integrated internationally, especially in the planning of refuge networks along migration corridors. Management actions in one p art of a flyway may affect the ability of areas elsewhere to meet obli gations to biodiversity conservation and maintenance of range under in ternational law. In populations that are limited by winter resources, creation of a refuge network may offer a mechanism to enhance populati on size, but more large scale density dependence studies are required to confirm this.