The habitat requirements of a resident population of Bittern Botaurus stellaris were investigated during the breeding season in a Mediterranean upland wetland, with particular reference to the area's isolation from other wetlands, its small size and hydrological conditions. Vegetation structure and water-level were described and associated with booming male and nesting female distribution within the marsh. A logistic regression model showed that water-level was the only significant factor affecting the distribution of booming males, which occupied areas seasonally flooded with shallower water (< 1 m). Females nested in seasonally flooded zones, while vegetation density appeared an important variable for nesting-site choice. Management of the wet area is discussed and the importance of a better understanding of the temporal dynamics of vegetation cover and spatial and temporal variations in water-level, and their possible effects on prey distribution, is highlighted.

The diet of the endemic Madeira Laurel Pigeon Columba trocaz in agricultural and forest areas of Madeira Island was studied in 1997 by means of microhistological analysis of 157 faecal samples, 94 from two of the main agricultural zones and 63 from a laurel forest. Cabbage was the most important component of the diet in agricultural areas, representing more than 54% of the optical fields analysed. Samples collected further from the forest contained a higher proportion of cabbage. Native fruits did not figure highly in the samples collected from agricultural areas and crop plants did not appear in the forest samples, suggesting a degree of dietary separation and that some individuals may concentrate on crops. Madeira Laurel Pigeon is normally a highly frugivorous species and fruit availability is relatively high in winter when the birds go to agricultural areas to feed. This suggests that it is not a shortage of natural foods that causes them to leave the forest. The unpopularity of the pigeon as a result of its pest status is the main threat to its existence. More information on the seasonal physiological requirements of Madeira Laurel Pigeon and the pattern of individual use of crops is needed to ensure the future conservation of this species.

There are no previous studies supporting the link between the decline of Roller Coracias garrulus populations in the Palaearctic and agricultural intensification. We studied the effect of farming practices on Roller reproduction during 1988–1991 in south-west Spain. Nest-boxes were installed on power pylons that crossed six different man-made habitats representing the most characteristic habitats in the Mediterranean region: pasture fields with and without holm oak Quercus rotundifolia trees, cereal fields with and without holm oak trees, scrub fields and irrigated fields. Rollers nesting in nest-boxes erected in unwooded pasture field had the highest breeding success, suggesting that this is the most suitable nesting habitat of Rollers in the region. There were no significant effects of farming practices in habitat adjacent to nests on Roller laying date and clutch size. However, after controlling for laying date, current agricultural practices around nests affected chick mortality, with higher losses in irrigated fields. Breeding success and egg productivity were also affected by farming activities, with the lowest values in irrigated fields. Future conservation plans for Rollers should consider that nest-box provision might increase habitat suitability for Roller reproduction and that highly intensified agricultural practices might have deleterious effects on Roller populations.

Crested Ibis Nipponia nippon is an Endangered species that has experienced a severe but short-lived population bottleneck in recent years. Only one wild population and two captive populations exist in China today, all of which were probably initiated from two breeding pairs rediscovered in 1981. This paper represents the first study of the genetic diversity of Crested Ibis by analysing sequence variation of a fragment spanning domains II and III of the mitochondrial DNA (mtDNA) control region of both wild and captive populations. Two haplotypes were identified in both wild and captive populations, and the captive population had a bias towards haplotype 1. The species as a whole demonstrated an extremely low level of genetic diversity, with a haplotype diversity and nucleotide diversity of 0.386 ± 0.074 and 0.069% ± 0.013%, respectively. Despite the rapid increase in numbers of birds under intensive management, the paucity of genetic diversity remains a real threat to the species. The mtDNA control region variations detected in the present study could provide significant information additional to the studbook data of Crested Ibis; therefore we suggest that special attention be paid to individuals with haplotype 2 when considering captive breeding management. Overall, great care should be taken in the selection of reintroduction sites for this rare bird, as species with low genetic diversity are thought to be more limited in their ability to tolerate a wide range of environmental extremes and diseases.

From March to July 2000, four seabird colonies in coastal ecosystems of Sinaloa, north-west Mexico were visited: on islets, a sandy beach and a long-abandoned salt-panning flat. There were partial and total breeding failures, most of them due to human activity. Amongst colonies of nine species, the breeding success of three was severely affected. All 250 Royal Tern Sterna maxima eggs were taken for direct consumption; 50% (75) of Blue-footed Booby Sula nebouxii chicks were killed for crab (Portunidae) fishing; and in a Least Tern Sterna antillarum colony (97 pairs), 50% failed due to disturbance from a fishing championship. Some of these species have priority status within Mexican and international conservation regulations. Certain aspects of these problems are discussed, and actions are suggested to balance conservation and the development of economic activities.

I analyse recent trends in the status and distribution of breeding birds of prey in the Canary Islands (Spain). Populations of Barbary Falcon Falco peregrinus pelegrinoides, Eleonora's Falcon Falco eleonorae, Sparrowhawk Accipiter nisus granti, Buzzard Buteo buteo insularum and Osprey Pandion haliaetus recovered throughout the 1990s. Egyptian Vulture Neophron percnopterus majorensis continues to be seriously threatened, with a total population of only around 130 birds. There is a lack of information on status of nocturnal birds of prey, especially of the Canary subspecies of Barn Owl Tyto alba gracilirostris, whose numbers seem to have decreased. Genetic studies should be carried out to clarify the taxonomic status of the birds of prey of the Canary Islands.