Royal Society for the Protection of Birds

About: Royal Society for the Protection of Birds is a nonprofit organization based out in Sandy, United Kingdom. It is known for research contribution in the topics: Population & Biodiversity. The organization has 670 authors who have published 1425 publications receiving 88006 citations. The organization is also known as: RSPB & Plumage League.

Use of preferred nesting habitat by stone curlews Burhinus oedicnemus in relation to vegetation structure

Abstract: The stone curlew is a nocturnal bird which nests and forages on sparsely vegetated ground. Its population and geographical range in Britain have declined throughout the 20th century. Estimates of the size of a sub-population in the Breckland region of eastern England show that a decline which began in the 1940s or earlier continued up to the mid-1980s, but that the population was stable from 1985 onwards. A survey in 1987 indicated that stone curlews nested at the highest densities on fragments of formerly much more extensive short semi-natural dry grasslands and heaths (referred to throughout as heathland). However, most pairs bred at much lower density on spring-sown tilled farmland. An important part of the decline in the Breckland stone curlew population between 1968 and 1991 is attributable to a decline in the number of pairs nesting on heathland. Observations of stone curlews marked individually with colour rings showed that individuals did not nest exclusively on heathland or arable farmland. Some birds nested in both habitats in the same year and there were frequent moves between habitats from one year to the next. Year-to-year changes in the number of pairs of stone curlews nesting on heathland during a period of population stability were associated with variation in both the rate of return to heathland of ringed birds which previously nested on heathland and the proportion of surviving young adults with no previous breeding experience which nested on heathland. Some of the birds which were displaced from, or failed to recruit to, heathland nesting sites nested on arable land, but there was also evidence that a proportion of them did not attempt to breed. Measurements of sward height at heathland sites with a recent history of occupation by nesting stone curlews show that those sites which had been abandoned had taller swards than those where the birds remained. An index of the biomass of green vegetation was derived from satellite imagery obtained before and after a sharp decline in the number of heathland nesting stone curlews. It was found that the index had increased significantly more at heathland sites which had ceased to be used by stone curlews than at sites which continued to be used for nesting. The long-term decline in the number of stone curlews nesting on heathland is believed to have begun with the conversion of large areas of heathland for arable agriculture and forestry. However, it has continued during a period when little heathland was lost. Changes in vegetation structure and species composition associated with a reduction in grazing by rabbits and livestock are the most likely cause. Since 1985 breeding success has been enhanced by protection of eggs and chicks in arable crops from destruction by farming operations. Beginning in 1989 efforts have also been made to change the management of Breckland heaths. These include shallow ploughing and increased grazing by livestock, supported by payments from government under the Environmentally Sensitive Areas scheme. The number and proportion of stone curlews nesting on heathland has increased and the decline in the total population size has ceased. The relative contribution of different management factors to this change is not yet clear.

A hotspot revisited – a biogeographical analysis of West African amphibians

Abstract: Aim The study was aimed at testing whether West Africa can be regarded as a distinct biogeographic region based on amphibian assemblages. If so, we asked what were the relationships of these assemblages with those in Central Africa, and whether West African amphibian distributions showed biogeographic substructure. We further investigated what events or processes may explain the observed patterns. Location Sub-Saharan Africa. Methods Presence–absence data of amphibian assemblages derived from field surveys and the literature were statistically analysed using three different multivariate techniques (consensus clustering, Monmonier analysis and nonmetric multidimensional scaling) to emphasize consistent results. Results We showed that West Africa has unique amphibian assemblages, which could be clearly demarcated from Central African assemblages, particularly by the geographic barrier of the Cross River. Further biogeographic subdivisions were detected to the west of this barrier. Habitat, mainly forest, was the best factor explaining our observed pattern. Overall, intra-regional similarity (e.g. within West Africa) was higher than intra-habitat similarity (e.g. within forest) across regions. Main conclusions Our results are compared with previous works and interpreted in the light of the known evolutionary history of West and Central Africa. The observed pattern may be explained by postulated differences in river continuity through time, with West African rivers serving as more or less constant barriers in contrast to those in Central Africa. Our results demonstrate the uniqueness of West African amphibian assemblages, highlighting the need for their conservation as many are under acute anthropogenic pressure.

The status and distribution of waders breeding on wet lowland grasslands in England and Wales

Abstract: Damp grasslands are disappearing at an alarming rate, due to drainage and agricultural changes Consequently their breeding waders have experienced fragmentation of range, with notable concentrations now at a few key sites A 1982 survey has provided a much-needed assessment of the current situation