The conservation uses of ringing data. Conclusions of the JNCC/BTO workshop, 4–5 November 1995, Norwich.

Abstract

1. The monitoring of both population size and demographic variables is important for understanding the causes of population changes. The main function of the Ringing Scheme should continue to be the monitoring of demographic variables, for a wide range of species. Ringing has an essential role in the monitoring of productivity, survival and dispersal. Numbers can also be monitored using ringing for some species. 2. Conservationists and policy‐makers require information on the movements of migratory species, particularly migrant passerines, waterfowl and seabirds. Analyses based on the mapping of ringing recoveries can provide much of the information that is required. An Atlas of Bird Migration based on ringing recoveries would fulfil many of these needs and identify areas where more detailed work is needed. There is scope for developing quantitative analyses of movements which incorporate regional variation in reporting rates, for example to estimate the proportions of different populations that use different wintering areas. 3. Ringing also provides information that is of value to conservation bodies working at a site or regional scale. Information for site inventories and on the use of different habitats within sites can be obtained from ringing studies at specific locations. Evidence of the populations which use particular sites can also be provided. Standardised long‐term projects based on particular sites are likely to be most useful for such purposes. 4. Full computerisation of ongoing data gathered by the Ringing Scheme is essential for addressing most questions concerned with population dynamics or movements. This is now being implemented. Recapture data should be computerised to facilitate analyses of survival rates. Selective computerisation of historical data will be necessary to support many of the analytical studies that are currently required for conservation purposes. 5. Sampling strategies for general ringing should to be reviewed in detail. The sample sizes required to estimate survival rates with adequate precision need to be assessed. The representativeness of the samples should also be considered. Ringing patterns of seabirds and waders are generally adequate to meet current monitoring requirements but need some specific extensions in terms of coverage and species targeted. More ringing of ducks is needed. In the short‐term a major shift in the emphasis of winter passerine ringing towards declining farmland species and away from catching at garden feeding stations is recommended. 6. More standardised ringing programmes should be developed, to increase the species and habitat coverage provided by the present Constant Effort Sites scheme. Long‐term coverage of sites and the use of recapture data to estimate survival rates should be emphasised. Colour‐ringing maybe needed in some cases. Designed passerine studies should be extended to farmland, woodland, rivers and other habitats in both summer and winter. Other potential target groups include seabirds, raptors using nestboxes, breeding waders, wintering waders, swifts, hirundines, tits and flycatchers using nestboxes, and low density passerines. Better integration of the Ringing and Nest Record Schemes would increase the quantity and value of data from both schemes. 7. Information from ringing needs to be combined with other population and environmental data in order to interpret population changes. Modelling approaches will generally be needed to understand how changes in demographic or environmental variables will affect population size. Similar approaches apply to many of the other potential uses of ringing data. 8. Better mechanisms need to be developed to co‐ordinate investigations of the causes of declines in particular species. These should include the development of extensive ringing projects that are closely linked to intensive studies undertaken by professional ecologists. Professional scientists, volunteers and policy‐makers should be involved in the design of such studies and in periodic appraisals of the results. Habitat‐based study groups, developing the model of the Wader Study Group, could be promoted, which would serve both to co‐ordinate the efforts of ringing‐based and other studies and to provide a forum for the exchange of ideas and discussions of research priorities. A Farmland Study Group is perhaps the highest priority in this respect. 9. Most ringing is carried out by volunteer ringers who would welcome opportunities to participate in specific projects and advice on how to better target their ringing. New projects must be well organised and provide good feedback to the volunteers involved. Ringing studies often need to be integrated with other work, and such projects might involve non‐ringer volunteers in resighting marked birds and gathering other observations. A Ringing Projects Officer would be required to undertake this work. 10. Many conservation problems involving migratory birds need to be addressed on a continental or fly way scale. The British and Irish Ringing Scheme should continue to work closely with other European schemes through EURING. Wherever possible projects should be integrated with work in other parts of Europe and Africa. Further expeditionary work is needed, particularly to study the ecology of Palearctic‐African migrants on their wintering grounds and of waders and waterfowl breeding in the Arctic. 11. Topic based workshops covered monitoring demography and numbers, diagnosing the causes of declines, passerine movements and winter ecology, waterfowl flyways, impacts of hunting and seabirds. Ringing is making major contributions to conservation‐oriented work in all of these areas. All of the workshops identified further specific projects or initiatives that could be developed within their respective areas. 12. The recommendations from this meeting will be incorporated in a scientific strategy for the BTO Ringing Scheme that is being developed by the Ringing Committee (see Bail lie, this volume). They will also inform discussions between the Country Agencies, JNCC and BTO regarding work to be undertaken within the JNCC/BTO partnership.