This paper presents estimated national and regional changes in numbers of breeding woodland birds in predominantly broadleaved woodland in Britain between the mid 1980s and 2003-04, derived from the Repeat Woodland Bird Survey (RWBS). A total of 405 sites across Britain for which historical data on bird populations were available were re-surveyed by BTO and RSPB fieldworkers during the RWBS. Changes were estimated separately for sites surveyed by the RSPB ( n = 252) and BTO ( n = 153) because of differences between the two groups in the field methods used in the original surveys. Changes between the 1960s and 1970s and 2003-04 were also estimated with the BTO data set only. The BTO and RSPB sites provide geographically complementary coverage of Britain and together provide much more widespread coverage than did the Common Bird Census (CBC), the former national monitoring scheme. Nationally, between the 1980s and 2003-04, six species declined significantly and three increased significantly based on the RSPB data, whereas eight declined and 13 increased according to the BTO data, with good correspondence between the changes recorded by the two data sets (only seven of 34 species showing trends differing in direction). Eight species showed large national declines ( > 25%) according to both data sets: The declines detected by the RWBS for Garden Warbler, Pied Flycatcher Ficedula hypoleuca and Common Redstart Phoenicurus phoenicurus were not evident from the national monitoring schemes. Most of the increases detected by the monitoring schemes were confirmed by the RWBS. However, the large increases detected by the RWBS for Coal Tit, Goldcrest, Great Tit and Eurasian Treecreeper were unexpected. All long-distance migrants have declined whilst medium-distance migrants (Blackcap and Common Chiffchaff ) have increased. Also, rare and specialist woodland species have fared less well than common and generalist species.
SummaryLaos is an important country for bird conservation. Bird surveys between 1992 and 1996, the first since 1949, covered 20 main areas, with incidental records from many others.This paper reviews the status of all Lao species reported to be of elevated conservation concern (key species) in any of the following categories: Globally Threatened or Globally Near-Threatened (sensu Collar and Andrew 1988 and Collar et al. 1994), and At Risk or Rare in Thailand (sensu Round 1988 and Treesucon and Round 1990). Several additional species are covered which have clearly undergone a National Historical Decline in Laos. A comprehensive review of other Lao species was not possible, and some species which are in truth of conservation concern have doubtless been overlooked. Historical and modern records were reviewed and population trends identified where possible.Current global status listings (Collar et al. 1994) were supported, except that consideration should be given to changing Red-collared Woodpecker Picus rabieri and Sooty Babbler Stachyris herberti from Threatened to Near-Threatened. If the Lao situation is representative of the species throughout their range, then consideration should also be given to placing Ratchet-tailed Treepie Temnurus temnurus and River Lapwing Vanellus duvaucelii as Near-Threatened.Twenty-seven Globally Threatened species are known from Laos, of which there are recent records of 22. There are recent unconfirmed records of two more. Forty-seven Globally Near-Threatened species are known from Laos, of which there are recent records of 39; there are unconfirmed records of one further species. Five Globally Threatened and five Near-Threatened species were recorded for the first time in Laos in recent years, suggesting that further species of elevated conservation concern remain to be found.
The British Willow Tit Poecile montanus kleinschmidti underwent a decline of 85% between 1970 and 2003. The cause of this decline is unknown. However, several hypotheses have been put forward to account for it: competition from other tit species, predation by Great Spotted Woodpeckers Dendrocopos major and habitat change. In order to test these, woods that are currently occupied by Willow Tits were paired with woods (within 50 km) that had been abandoned by Willow Tits five or more years previously. Point counts for other tit species (potential competitors) and woodpecker species (potential predators) were carried out at ten evenly spaced points throughout each wood. Habitat variables were collected within a 50-m radius of where a Willow Tit was located (in the occupied woods) or where maps showed a Willow Tit had been located (for abandoned woods). No evidence was found for differences in numbers of potential competitor or potential predator species in abandoned and occupied woods. Soil water content was found to be higher at occupied sites. No other habitat features differed between the two categories of site. The drying up of British woods could therefore be implicated in the Willow Tit decline and this warrants further investigation.
SummaryThe Giant Ibis Pseudibis gigantea was formerly more widespread in mainland South-East Asia, being found in Thailand, Cambodia, Laos and Vietnam. However, it has always been scarce throughout its range and has declined dramatically over the past 50 years as a result of habitat destruction, disturbance and hunting. This paper documents the species's decline with a review of all previous records including the recent sightings between 1993 and 1995, and suggests conservation measures to be taken for its continued survival.
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