Distribution, habitat use and selection, ranging behaviour, diet and food supply of the stone curlew Burhinus oedicnemus were studied in a small, fragmented population at the north-western edge of its world range. Stone curlews bred on short semi-natural grassland and spring-sown arable farmland in areas with sandy soils with stones or rubble. They were most active at night and travelled up to about 3 km from the nest to forage. Individuals used a fragmented home range comprising an average of 30 ha of short seminatural grassland, short improved pasture and spring-sown crops for foraging. Earthworms, soil-surface arthropods and molluscs were the main prey; the proportion of earthworms being lowest when the soil was dry. Breeding densities were highest on short semi-natural grassland. Stone curlews were most likely to breed on a spring-sown arable ®eld if the crop was of a type that became tall and dense relatively late in the summer and if the ®eld was close to short semi-natural grassland or sheep pasture and distant (> 3 km) from the nearest major road. Sparse vegetation and bare ground were the most obvious characteristics of habitats preferred for nesting and foraging.

Gyps vulture populations across the Indian subcontinent collapsed in the 1990s and continue to decline. Repeated population surveys showed that the rate of decline was so rapid that elevated mortality of adult birds must be a key demographic mechanism. Post mortem examination showed that the majority of dead vultures had visceral gout, due to kidney damage. The realisation that diclofenac, a non-steroidal anti-inflammatory drug potentially nephrotoxic to birds, had become a widely used veterinary medicine led to the identification of diclofenac poisoning as the cause of the decline. Surveys of diclofenac contamination of domestic ungulate carcasses, combined with vulture population modelling, show that the level of contamination is sufficient for it to be the sole cause of the decline. Testing on vultures of meloxicam, an alternative NSAID for livestock treatment, showed that it did not harm them at concentrations likely to be encountered by wild birds and would be a safe replacement for diclofenac. The manufacture of diclofenac for veterinary use has been banned, but its sale has not. Consequently, it may be some years before diclofenac is removed from the vultures' food supply. In the meantime, captive populations of three vulture species have been established to provide sources of birds for future reintroduction programmes.

The Northern Bald Ibis or Waldrapp Geronticus eremita is a species of arid semi-deserts and steppes, which was formerly widely distributed as a breeding bird across North Africa, the Middle East and the European Alps. Just over 100 breeding pairs now remain in the wild at two sites in Morocco whilst two further wild pairs remain in Syria. There is also a population in Turkey, which is maintained for part of the year in captivity, and a large captive population in zoos. The species is classified by IUCN as ‘Critically Endangered’, the highest threat category. The wild population has grown during the past decade, which represents the first evidence of population growth in the species' recorded history. Conservation action in Morocco has contributed to this recovery. A large part of the contribution of research to conservation action has been to establish and document the value of simple site and species protection. Quantitative assessments of the importance of sites for breeding, roosting and foraging have helped to prevent disturbance and the loss of sites to mass-tourism development. Wardening by members of the local community have reduced disturbance by local people and others and increased the perceived value of the birds. Monitoring has suggested additional ways to improve the breeding status of the species, including the provision of drinking water and removal and deterrence of predators and competitors. These actions have been evaluated by subsequent testing. Steppe and two-year fallows were shown to be the key feeding habitats, and maintaining such non-intensive land uses in future may present major management challenges. The recovery in the Souss-Massa region remains precarious because the population is concentrated in a few places where adverse changes are possible. However, it could provide opportunities for natural extension of the range to formerly occupied sites further north in Morocco.

The main wild population of the Northern Bald Ibis Geronticus eremita breeds on the Atlantic coast of Morocco in the Agadir region. This paper describes the numbers of breeding pairs over the last two decades, the recent breeding performance, the causes of egg and chick losses and their conservation implications. Since 1980 there has been no overall decline in numbers with, over the last 5 years, 59–74 pairs breeding and a peak prebreeding population of around 220 birds. In contrast with the now extinct Northern Bald Ibis populations in Turkey and elsewhere in Morocco, the birds are present in the Agadir region throughout the year and do not appear to migrate from the area outside the breeding season. Breeding performance is highly variable from one year to the next but does not appear to be related to rainfall in the vicinity of the colonies as has been reported elsewhere. It is suggested that coastal fogs in this region may buffer the adverse impacts of low rainfall and may in part account for the year‐round residency of the birds. The main causes of breeding failures have been loss of eggs to predators and, most importantly, poor chick survival as a result of starvation and predation. Conservation action to date has focused on reducing the negative influences on breeding success but it is recognized that for such a long‐lived bird adult survival is also likely to be an important limiting factor on the population size.

Summary 1.Jerdon's courser Rhinoptilus bitorquatus is a nocturnally active cursorial bird that is only known to occur in a small area of scrub jungle in Andhra Pradesh, India, and is listed as critically endangered by the IUCN. Information on its habitat requirements is needed urgently to underpin conservation measures. We quantified the habitat features that correlated with the use of different areas of scrub jungle by Jerdon's coursers, and developed a model to map potentially suitable habitat over large areas from satellite imagery and facilitate the design of surveys of Jerdon's courser distribution. 2. We used 11 arrays of 5-m long tracking strips consisting of smoothed fine soil to detect the footprints of Jerdon's coursers, and measured tracking rates (tracking events per strip night). We counted the number of bushes and trees, and described other attributes of vegetation and substrate in a 10-m square plot centred on each strip. We obtained reflectance data from Landsat 7 satellite imagery for the pixel within which each strip lay. 3. We used logistic regression models to describe the relationship between tracking rate by Jerdon's coursers and characteristics of the habitat around the strips, using groundbased survey data and satellite imagery. 4. Jerdon's coursers were most likely to occur where the density of large (> 2 m tall) bushes was in the range 300-700 ha − 1 and where the density of smaller bushes was less than 1000 ha − 1 . This habitat was detectable using satellite imagery. 5. Synthesis and applications . The occurrence of Jerdon's courser is strongly correlated with the density of bushes and trees, and is in turn affected by grazing with domestic livestock, woodcutting and mechanical clearance of bushes to create pasture, orchards and farmland. It is likely that there is an optimal level of grazing and woodcutting that would maintain or create suitable conditions for the species. Knowledge of the species' distribution is incomplete and there is considerable pressure from human use of apparently suitable habitats. Hence, distribution mapping is a high conservation priority. A two-step procedure is proposed, involving the use of ground surveys of bush density to calibrate satellite image-based mapping of potential habitat. These maps could then be used to select priority areas for Jerdon's courser surveys. The use of tracking strips to study habitat selection and distribution has potential in studies of other scarce and secretive species.

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Weak environmental assessments undermine regulations

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