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Woodland management for birds: Birds and woodlands in Wales

1 Woodland birds in Wales

What is a woodland bird?

The Repeat Woodland Bird Survey

There are many ways of defining species- habitat associations. In this guide the basis of a definition of a woodland bird has been taken from The New Atlas of Breeding Birds in Britain and Ireland (Gibbons et al. 1993). A few changes have been made, eg where woodland habitats in Wales hold a high proportion of the Welsh population of a particular species.

Trends in woodland birds in Wales

Population trends of widespread woodland birds are measured annually by the BTO/JNCC/RSPB Breeding Bird Survey (BBS), and recently by the BTO/ RSPB Repeat Woodland Bird Survey (RWBS). The former is used to calculate the Welsh Assembly Government’s wild bird indicator, a measure of the quality of the Welsh environment.

Due to growing concerns over declines in woodland bird populations in the UK, the RSPB and the BTO Carried out a re-survey of breeding bird populations of mixed and broadleaved woodlands in 2003 and 2004, the Repeat Woodland Bird Survey (RWBS). Woodland plots were surveyed, repeating those first Carried out in the same plots mainly in the 1980s but also, for a sample of sites, in the 1960s and 1970s. In Wales, 56 woodlands were surveyed by the RSPB using point count methods, and 12 woodlands by the BTO using territory-mapping methods. Although the RSPB and BTO datasets were complementary, giving wide geographical coverage, the methods of data collection differed between the two sets, so these were analysed separately with two sets of trends (an RSPB and a BTO) being given for a particular species over the time period. The RWBS trends are presented in the species accounts in Part 3.

The Breeding Bird Survey

The woodland bird indicator

The BTO/JNCC/RSPB Breeding Bird Survey (BBS) was launched in 1994 with the aim of improving the geographical scope of UK bird monitoring by including all habitats, and therefore more species of breeding birds than had the previous Common Birds Census (CBC). Since the final year of the CBC in 2000, the BBS has become the primary scheme for monitoring the population changes of our common and widespread bird species in the UK.

By surveying more than 2,000 sites each year, it is possible to routinely generate UK population trends from BBS data for more than 100 species. Population changes can also be provided for all four constituent UK countries, including Wales, the data being used to produce the Welsh wild bird indicator, including the woodland bird indicator (see below). The current BBS trends for the species considered in this guide are presented in the species accounts in Part 3.

The health of bird populations in Wales is a measure of the quality of our environment. The Welsh Assembly Government measures this using its two- part headline indicator based on different groups of bird species. The BBS (see above) has been used to monitor widespread birds since 1994, and the data is used by the Welsh Assembly Government for the first part of its indicator, published annually in Sustainable indicators for Wales. The indicator shows short-term change in abundance (numbers) of the 58 native species measured by the BBS since 1994. The indicator must always be considered within the context of long-term changes. This is provided by part two of the indicator that shows changes in range (geographical distribution) between 1968– 1972 and 1988–1991. The indicator shows little evidence of an overall trend in woodland bird abundance over the short- term (Figure 1, over), with abundance


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