Contents of report
Breeding Bird Survey
Common Birds Census
Constant Effort Sites
Nest Record Scheme
Waterways Bird Survey
Alerts
Summary
What the categories mean
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4. DISCUSSION

4.7       Future Developments

The key development in this report is to provide it as a web-based report.  This allows the provision of a much greater range of information and results than previously, increasing the applicability of BTO information and its use by conservation and other bodies.  In the future, we hope to introduce other web-based features, such as the ability to undertake interactive, user-defined tabulations of the data.  This will serve to increase the value of the information and increase its usefulness for wider range of applications.

In the last report (Crick et al. 1998), several potential future developments have, indeed, been implemented in this new report.  Thus, we have introduced more appropriate regression analysis (Loglinear Poisson regression for population indices) and Generalised Additive Model smoothing techniques.  We have also implemented a more sophisticated system of alerts that we hope will have a broad applicability within the conservation science sphere.

While some moves have been made toward the provision of regional information, by the provision of country indices from the BBS, there is more that could be done in this regard, particularly for CBC, WBS, CES and NRS data, where there are sufficient sample sizes to permit this.  Other types of categorisation have yet to be implemented and will need discussion with JNCC and the Country Conservation Agencies.  The use of Landscape-based reporting (derived from perhaps the Countryside Survey 2000, organised by the Centre for Ecology & Hydrology) or, perhaps more appropriate species-specific habitat-based reporting could be considered.

Some form of survival rate monitoring is possible through the use of the BTO Age Specific Totals dataset derived from the Ringing Scheme. These were introduced in 1985 to collect cohort sizes (the numbers of adults, juveniles, pulli and unaged) of birds ringed during the summer (April to September) of each year (Baillie & Green 1987).   Twenty-two species of passerine are included, covering a range of common migrant and resident birds.  This information, when combined with information on the numbers of ringed birds recovered each year, allows the calculation of age-specific survival rates, while accounting for age- and year-specific variation in recovery reporting rates.  Without information from the Age Specific Totals Lists, recovery reporting rates must be assumed to be constant, which could lead to biases in estimates of survival (Baillie & McCulloch 1993).  Ringing data submitted on disk will soon extend the range of species for which such analyses are possible.  It should be possible to provide further information on changes in survival in future reports.

4.8      Conclusion

We hope that this report will be both useful as a ready source of information for the day-to-day use of conservation practitioners and as a source of information for those involved in more strategic conservation policy making.  The information presented here is very much the tip of the data iceberg held by the BTO, providing a concise overview and pointers about how populations are changing and where further research and conservation action needs to be taken. 

The report raises Alerts due to declines in population size or breeding performance for a considerable number of species.  These alerts will help inform conservation organisations when they are drawing up their plans for priority work, especially as the current lists, such as the Conservation Importance List, quickly become dated.

The information in this report on demographic factors will also help conservation organisations to target their resources more effectively.  For declining species of conservation importance, declines in breeding performance show that conservation action may need to be targeted at the breeding season; the lack of a decline in breeding performance suggests that either loss of habitat or changes in the factors affecting survival are more likely to be playing a role rather than factors affecting nesting success.

Finally, we hope that users of this report will provide feedback on how the report can be improved in the future.  We will welcome comments on more general aspects of this report if they help us to produce a better and more useful product in the next edition.

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The report should be cited as: Baillie, S.R., Crick, H.Q.P., Balmer, D.E., Bashford, R.I., Beaven, L.P., Freeman, S.N., Marchant, J.H., Noble, D.G., Raven, M.J., Siriwardena, G.M., Thewlis, R. and Wernham, C.V. (2001) Breeding Birds in the Wider Countryside: their conservation status 2000. BTO Research Report No. 252. BTO, Thetford. (http://www.bto.org/birdtrends)

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