We present a comparative analysis of correlates of Red data book status that controls for phylogeny. As a model system we use 244 species of hoverfly (Diptera: Syrphidae) from the British fauna, with their Red data book statuses in Britain and three regions of Germany. The analysis is confined to four adult characters, with Red data book status as the dependent variable. Associated with an increase in risk of extinction were a decrease in flight period and an increase in wing length (in two regions). Variables representing the number of habitats occupied and whether species were single- or multi-brooded were not associated with an increase in risk of extinction. At this stage we restrict our analysis to the identification of patterns rather than speculation as to causal mechanisms, but the patterns themselves are of value to conservation biologists, provided the methods used to identify them control for the possible confounding effects of phylogeny.

Fluctuating asymmetry (FA), a measure of developmental stability, has been proposed as a simple technique for identifying populations suffering from inbreeding and a loss of genetic diversity. However, there is controversy regarding the relationship between FA and both allozyme heterozygosity and pedigree inbreeding coefficients (F). FA of sternopleural bristle number in Drosophila melanogaster was measured in populations maintained at effective sizes of 25 (8 replicates), 50 (6), 100 (4), 250 (3) and 500 (2) for 50 generations (inbreeding coefficients of 0.05—0.71). FA was calculated from the same data set using three different indices (FA1, FA5 and FA6). There was no significant relationship of FA with pedigree inbreeding coefficients for any of the three indices. The relationship between FA and allozyme heterozygosity was non-significant for indices FA5 and FA6 (the more powerful indices) and only significant for FA1. A second comparison of highly inbred (F ≈ 1) populations with their outbred base population showed significantly greater FA in the inbred populations only when analysed with FA6. Analysis of the same data using FA1 and FA5 showed non-significant relationships in the opposite direction. If a relationship between FA and genetic diversity does exist, it is weak and inconsistent. Consequently, our results do not support the use of FA as a monitoring tool to detect inbreeding or loss of genetic diversity.

We surveyed birds in cacao (Theobroma cacao) plantations in the state of Tabasco, Mexico. The shade canopy was planted by farmers and consisted of approximately 60 species of trees with no single dominant species. Canopy height averaged 15 m and the structure was multi-storied. We conducted 220 ten minute, 25 m radius point counts for birds and detected 1550 individuals from 81 species. The average number of birds/point and the expected diversity in a fixed number of individuals within the cacao surveyed were well within the range of other lowland habitats, including agricultural sites, that we have surveyed previously in neighbouring Chiapas. In the Tabascan cacao, the migrant group was composed, in part, of forest species, and dimorphic species were represented primarily by males, which in other areas are known to dominate forest or forest-like habitats. In contrast to the composition of migrant species, we found few resident forest specialists in Tabascan cacao. Instead, the tropical resident group was composed of large-bodied generalist species that use small patches of trees in open habitats. These results (moderate diversity, low numbers of forest specialists) differ from the few studies completed in ‘rustic’ cacao systems located near large tracts of forest. The planted shade cacao agroecosystem – at least in the absence of nearby forest – may have a limited value for conserving lost tropical forest bird diversity, but it provides habitat for woodland-associated migratory species. Our results also indicate that the planted shade cacao plantations supported few small omnivorous or frugivorous species, probably because cacao itself, as well as the dominant shade trees, produce primarily mammal or wind dispersed fruit and seeds.

The number of tiger subspecies is a major conservation issue that is difficult to resolve owing to small fragmented extant populations and limited historical samples in museums, which compromise the rigour of both molecular and morphological taxonomic studies. Rather than considering a static taxonomic approach to geographical variation in the tiger, we consider the changing biogeographical range of the tiger through the last glacial-interglacial cycle, based on habitat associations of modern tiger specimen records, and environmental reconstructions from the Last Glacial Maximum (LGM; approximately 20000 years before present (B.P.)). We regard this cycle as representative of the numerous glacial cycles that span the evolutionary history of the tiger since its appearance in the fossil record about two million years ago, thereby giving a deep-time perspective. The key issue is to determine the extent to which ancestral populations of the tiger were geographically isolated. If no geographical isolation is likely, and gene flow between tiger populations could be maintained until modern times, then diagnosably distinct populations could not have evolved. Our reconstructions show that only two tiger populations were likely to have experienced significant geographical isolation from the main species distribution; these were to the west of Tibet (during the LGM) and on Japan (throughout the glacial cycle). In addition, the LGM is likely to have seen the partial separation of peninsular Malayan and Sunda Islands tigers from mainland populations. From a biogeographical perspective it seems probable that only three contemporary populations were sufficiently separated for the evolution of distinct populations, which can be regarded as subspecies or evolutionary significant units. Therefore, most variation in modern tiger populations is probably clinal, which has important implications for future conservation strategies both in the wild and in captivity.

The general problem of evaluating the potential success of mammalian reintroduction plans has been tackled by a case study illustrating a four-phase approach to finding and assessing potential sites for the reintroduction of European beavers, Castor fiber, to Scotland, combining the use of Geographic Information Systems (GIS), fieldwork and population modelling. Phase 1 used GIS to investigate the wider availability of habitat for beavers in Scotland, and predicted that there is the capacity to support in the order of 180 to 390 beaver families. Phase 2 involved the preliminary assessment of nine sites using brief field surveys. Phase 3 focused further on the three most suitable sites, where a thorough habitat survey was used as a basis for calculating carrying capacities of between three and five families. Finally, phase 4 used population modelling to assess the viability and likely spread of beavers following release at these three best sites. High, medium and low parameters were derived from the literature, and populations were predicted to persist and spread as long as at least the medium parameters were used. This exercise illustrates the power of combining field surveys and GIS-based population modelling as a tool for planning reintroductions in general, and as a foundation for planning the reintroduction of beavers in particular.

Genetic variation at the major histocompatibility (MHC) class I loci was examined in captive and wild samples of three subspecies of tiger (Bengal, Panthera tigris tigris; Siberian, P. t. altaica; Sumatran, P. t. sumatrae) by Southern blot analysis using the domestic cat probe FLA 24. All captive populations showed at least moderate variability compared to other felids. Captive tigers were, on average, significantly more variable than wild tigers, but this was not consistent among subspecies. Significant geographic genetic population structure was found at the MHC class I loci among both captive and wild tigers. Phylogenetic analysis of both captive and wild tigers placed Sumatran tigers basally. In a combined phylogenetic analysis, captive and wild tigers of the same subspecies occurred near one another, indicating that the structure of the captive populations reflects that of the wild populations.

Five out of 169 fertile California condor (Gymnogyps californianus) eggs laid in captivity have exhibited chondrodystrophy, a lethal form of dwarfism. Pedigree records indicate that this chondrodystrophy, like similar conditions in chickens, turkeys and quail, is probably inherited as an autosomal, recessive allele. We estimate that the frequency of this putative allele is about 9%. This high frequency is probably due to a founder effect. We consider three management options for the allele: ignoring it, eliminating it by selection and minimizing its phenotypic manifestation by avoiding matings between possible carriers. We recommend minimizing its phenotypic expression because an unacceptably large proportion of condors (up to 78 out of 146) would be prevented from breeding under a selection strategy designed to eliminate the allele. We predict that many captive populations will prove similar to the California condor population in that it will prove inadvisable or impractical to select against one or more deleterious alleles detected in the population.

There are many methods available for evaluating conservation priorities. Traditional methods of species richness, genus richness and critical species counts were compared with newer methods of phylogenetic and genetic diversity. Conservation priorities for areas designated by the Interim biogeographic regionalisation for Australia (Thackway & Cresswell, 1995) were assessed on the basis of the freshwater crayfish fauna of Australia. Distributions for all crayfish species were taken from the literature, and plotted in the IBRA areas. Species and genus richness, as well as the number of rare or endangered species were calculated for each area. A phylogeny of 35 representative crayfish based on 16 S rDNA sequence data was used to assess phylogenetic and genetic diversity of species and genera. Methods of species richness and phylogenetic diversity agreed to a large extent in their ranking of areas, both methods agreed that the north-west coast of Tasmania and the south-eastern portion of the continent were of highest priority for conserving the greatest amount of diversity. These results differ greatly from high priority areas based on other taxonomic groups, emphasizing the importance of broad taxonomic and ecological sampling in making conservation decisions.

The current extinction crisis is caused primarily by human impacts upon wild populations. Large carnivores are especially sensitive to human activity; because their requirements often conflict with those of local people, predators have been actively persecuted in most regions of the world. In this paper, the impact of people upon predators is analysed by relating local carnivore extinctions to past and projected human population densities. There are strong associations between high human density and the loss of carnivore populations from a region. Interspecific variation in ability to survive at high human densities probably reflects species' ability to adapt to human-modified habitats. However, regional and temporal variation in individual species' sensitivity to human density is more likely to reflect the activities of local people than the phenotypes of local carnivores. Local culture, government policy and international trade all influence human attitudes to predators and, therefore, the impact of people upon carnivore populations. The importance of these factors may mean that extinction risks for carnivores will continue to increase, even though human population growth is projected to deccelerate during the new millennium. This points to an urgent need for techniques to resolve conflicts between people and predators at either the local or landscape level.

Habitat selection by translocated black howler monkeys (Alouatta pigra) was studied in Belize, Central America. Ranging patterns of two recently translocated groups were contrasted with those of two groups in the same area with established home ranges, on a yearly and monthly basis. All groups concentrated their activities along stream beds at elevations below 200 m. Newly translocated groups increased the percentage of their monthly ranges in riverine areas (within 100 m of a water source) over the year of the study (with the exception of the last month) while established groups did not. Areas used more than five times by the monkeys contained larger trees and a greater relative coverage of major food species than low-use areas even though they had a lower overall species richness and diversity. These monkeys may be selecting habitat within the forest based upon vegetative differences and ranging patterns may be affected by patterns of food availability.