Adequate monitoring of amphibian populations will be increasingly important if global declines are to be understood and, where possible, reversed. The natterjack toad, Bufo calamita, is the rarest British amphibian and has been the subject of substantial conservation efforts. Monitoring strategies have aimed to quantify both the total numbers of populations and the status of individual populations. Between 1970–1999 the number of natterjack populations increased from 43 to 48 because successful translocations (11) outnumbered extinctions (6). Efforts to monitor individual populations increased over the period 1970–1999. Between 1990–1999 there were no detectable trends in B. calamita population size or breeding success in Britain, although power to detect any trends over 10 years was low. Calling activity and short-term trends in spawn counts were unreliable predictors of long-term population viability in the absence of extra information such as toadlet production. Long periods (> 10 years) of spawn counts are needed to demonstrate trends that are reflective of real population changes at the national level. Efforts to develop reliable methods for monitoring B. calamita in Britain could provide useful guidelines for work on some other declining species of amphibians.

Island populations are an interesting dichotomy in conservation biology. On the one hand, they can be a refuge for species where mainland populations have been decimated by loss of habitat and predation by exotic predators. On the other hand, island populations usually have reduced genetic diversity and are more susceptible to extinction through genetic and demographic processes. Genetic variation and morphological characters were measured for island and mainland populations of Parantechinus apicalis, small dasyurid marsupials, restricted to southwest Australia. Genetic variation at seven microsatellite loci revealed low levels of heterozygosity (He = 0.20−0.44) and high levels of inbreeding (Fe = 0.40−0.72) in island populations compared with the mainland population (He = 0.73). A nested clade analysis revealed that allopatric fragmentation was probably responsible for the association between geographical location and control region haplotypes, which is consistent with the isolation of populations on islands and indicative of two main populations of P. apicalis representing separate conservation units for management. While these results are typical of many island populations, they have important implications in terms of the conservation of threatened species in Australia and around the world, where island populations are a common source of founders for captive breeding and translocation to mainland sites.

Eastern collared lizards (Crotaphytus collaris collaris) on the Ozark Plateau of southern Missouri are restricted to islands of rocky glade habitat located throughout the oak-hickory forests of the region. Human mediated suppression of fire negatively impacts collared lizard populations by permitting the overgrowth and consequent disappearance of this glade habitat and also leads to a dense forest understorey that impedes movement of lizards between glades. We present data examining the effects of a fire management regime on collared lizard populations we monitored via mark/recapture from 1998 to 2001. We demonstrate increased glade-to-glade dispersal, colonization of previously unoccupied glades, and a significant increase in population size in the burned area. In addition, we show that populations within burned areas exhibit body sizes similar to those reported for populations living on healthy habitat as compared to those living on habitat that has deteriorated because of fire suppression. We conclude that managed forest fires positively impact collared lizard populations in the Ozarks, promoting factors that increase the long-term sustainability of the species.

The importance of diseases of domestic animals in the conservation of wildlife is increasingly being recognised. Wild carnivores are susceptible to many of the pathogens carried by domestic dogs and cats and some of these pathogens have caused disease outbreaks and severe population declines in threatened species. The risk of disease spillover from domestic to wild carnivores in South America has not been extensively investigated. This study examined the disease exposure of domestic carnivores living near a protected area in Bolivia. Forty dogs and 14 cats living in three towns on the eastern border of Madidi National Park were sampled. High levels of exposure to canine distemper virus, canine parvovirus, Sarcoptes scabiei and Toxoplasma gondii were found among domestic dogs, with similarly high levels of exposure to feline parvovirus, feline calicivirus and T. gondii being found among domestic cats. If contact occurs between domestic and wild carnivores, disease spillover may represent an important risk for the persistence of wild carnivores in the region. Additional research is therefore necessary to determine if wild carnivores living in proximity to these domestic carnivore populations are being exposed to these pathogens.

In this study we investigate some applications of genetic markers in animal conservation, using the Arabian oryx (Oryx leucoryx) as an example. Out of 66 sets of microsatellite primers from other ruminants, 58% were found to amplify microsatellites in Arabian oryx. Polymorphism (50% of loci amplified) and allelic diversity (mean 2.1 alleles/locus amplified) were within the range found in other ruminants. Arabian oryx (n = 343) representing most of the major groups world-wide were typed at six loci. Low but significant population differentiation was found between most oryx groups, suggesting that management of Arabian oryx has led to substantial genetic mixing between populations. Forty percent of the alleles in one additional Arabian oryx sample from the pre-extinction population in Oman were not found in any contemporary Arabian oryx, and two out of four contemporary populations were deficient in rare alleles, suggesting that the species has lost some neutral genetic variation. The microsatellite loci were sufficiently polymorphic for identification of an Arabian oryx sample in a forensic context, but were not sufficiently polymorphic for large-scale parentage inference. We suggest that it is important to evaluate whether genetic markers are likely to have sufficient power to answer particular conservation questions prior to committing conservation resources to genetic typing.

Modern concrete dams have devastated fish populations world-wide. However, dams vary greatly in how they are engineered and operated, and thus pose a range of threats to riverine fauna. Understanding the differences in the impacts of dams is critical for setting conservation priorities. We used a modified BACI (before-after-control-impact) sampling design as a means to quantify the effects of dams on spring/summer chinook salmon in two watersheds (Snake and Upper Columbia Rivers) of the Columbia River Basin, USA. The construction of four dams in the Columbia River Basin from 1966 to 1975 allowed us to test the hypothesis that the presence of these dams does not affect the abundance, survival and population growth of chinook salmon. In both the Snake and Upper Columbia Rivers, there was a significant decline from the period before dams were constructed (1959-65) to the period after dams were constructed (1980-90). In the Upper Columbia River, declines in productivity or population performance (measured as recruits per spawner or Ricker function residuals) were greater than in the control region. On the other hand, patterns of fish productivity in the Snake River were similar to those seen in the control region. The disparity between fates of Upper Columbia and Snake River populations points to the differences between regions in current efforts to reduce fish mortality associated with dams. Our analysis suggests that dams in the Upper Columbia River, but not Snake River, are a potential force preventing recovery of endangered salmon populations.

The Mexican gray wolf appears to be extinct in the wild and exists now only in captivity and as a reintroduced population in southeast Arizona and southwest New Mexico. A recent study did not find evidence for inbreeding depression in juvenile viability or litter size in captive animals. Here we found that captive wolves with little or no known inbreeding had lower body size than wild-caught wolves. In addition, captive wolves with higher inbreeding had lower body size than captive wolves with little or no inbreeding. The captive population was descended from three founders until two other lineages, each descended from two founders, were recently added to the population. There has been concern that the offspring from matings between these lineages may differ from the individuals in the original lineage so we examined the potential statistical power to detect differences between body size for animals from cross-lineage matings and other matings. In endangered species there are often limited opportunities to obtain sample sizes large enough to detect statistically significant differences because of the extensive resources needed to produce and maintain captive animals. In this case, however, it appears from our examination that in the next few years there will be an adequate sample size to evaluate statistically the differences in body size between these groups.

A new species of barking deer (Muntiacus spp.) is described from northern Myanmar. Diagnostic DNA character data are presented along with preliminary information on morphology, distribution, and phylogenetic relationships. This discovery contributes significantly to our knowledge of this poorly studied group and highlights the importance of continued field surveys in remote regions. Similar studies have resulted in a significant increase in conservation efforts in other parts of South-east Asia, and argue for additional conservation efforts for this region.

Exotic predators, particularly red foxes (Vulpes vulpes) and feral cats (Felis catus), have been implicated in the declines and extinctions of many Australian mammals and a recent incursion of foxes into Tasmania has therefore caused great concern. We tested the behavioural responses of eastern quolls (Dasyurus viverrinus) to acoustic cues of native (masked owl (Tyto novaehollandiae castanops) and Tasmanian devil (Sarcophilus laniarius)) and non-native (fox and cat) predators and to non-predators (cow (Bos taurus) and control noise). Juvenile quolls treated fox vocalisations like those of cows (as measured by an increase in movement), in contrast to their responses (a decrease in movement) to sympatric predators. Cats are probably a lesser threat to eastern quolls than native predators or foxes, their impact probably being greatest on the juveniles. Juvenile quolls, but not adults, showed similar responses to cat vocalisations as they did to owls and devils. Adult quolls responded differently from juveniles to owls and devils, by increasing vigilance. This is consistent with the smaller body size, inexperience and the presumed greater vulnerability of juveniles to predation. The lack of appropriate anti-predator responses to foxes suggests that eastern quolls would be vulnerable to predation by foxes in Tasmania.

How well can indicator groups, as sets of species with well-known distributions, represent the distribution of overall biodiversity to select networks of areas for conservation? In the literature, reliable indicator groups of complementarity have proven difficult to find, with some taxon-based indicator groups resulting in no more species represented than when areas are chosen at random. We rigorously test which quantifiable characteristics of species make them better components of indicator groups of complementarity in area networks. We find that even indicator groups comprised of randomly chosen, taxonomically unrelated species perform better than randomly chosen areas, and we demonstrate the improved efficiency of protected-area networks possible when using indicator groups chosen on the basis of species' characteristics.

Much of the demand for turtle meat in North America and Europe during the past four centuries has been met using green turtle (Chelonia mydas) and other marine turtles. As stocks of marine turtles dwindled, harvest of the alligator snapping turtle (Macroclemys temminckii), the largest freshwater turtle in North America, increased in the south-eastern USA. As a result, this species has declined and is now protected in every state of the USA except Louisiana. There is concern that the remaining legal trade in turtle products may serve as a cover for illegally harvested species. To assess the composition of species in commerce, we purchased 36 putative turtle meat products in Louisiana and Florida. Using cytochrome b and control region sequences of the mitochondrial genome, we identified 19 samples as common snapping turtle (Chelydra serpentina), three as Florida softshell (Apalone ferox), one provisionally as softshell turtle (Apalone sp.), one as alligator snapping turtle, and eight as American alligator (Alligator mississippiensis). It appears that M. temminckii is no longer the predominant species in markets of Louisiana. The presence of alligator meat in a quarter of the samples indicates that the trade in turtle products is not entirely legitimate. As is often the case for unsustainable wildlife harvests, large, esteemed species, such as green turtle and alligator snapper, have been replaced by smaller, more-abundant or mislabelled species, a phenomenon we refer to as the mock turtle syndrome.

With the increasing human population world-wide, animals and humans are sharing more habitat. In this study, we consider the consequences of this habitat usage overlap on the behaviour patterns and social structure of a threatened species. Specifically, we used focal animal samples to collect data on the Cuban rock iguana, Cyclura nubila, in six field sites. Three of these sites are subject to considerable anthropogenic habitat usage, whereas three are in relatively low anthropogenic usage areas. Individuals in high anthropogenic usage sites were more closely assembled, with more males and females sharing a smaller amount of space. These animals exhibited even more aggressive behaviour and social interactions than expected when taking into account the larger number of possible interactants. High anthropogenic usage sites also had more male–male interactions and fewer males interacting with females. We suggest that social and mating system changes have occurred. Ramifications of these recent changes in the behavioural repertoires on the long-term survival of the species are discussed.

The demographic relationship between life-history variation and environment may form a foundation for developing conservation strategy. We predicted that grouping 52 North American carnivore species based on life-history modules (reproductive output and reproductive chronology) would highlight differences in adaptations to particular environments. We tested whether differences among life histories related to particular environments classified according to primary productivity and seasonality into a 2 × 2 table. We found that bet-hedgers (e.g., bears, martens, fishers) have evolved life history adaptations to unpredictable environments, marine carnivores (e.g., seals) have evolved highly competitive abilities, and other terrestrial carnivores show adaptations to high reproduction (e.g., neotropical felids and procyonids) or survival (e.g., foxes and skunks). For example, ‘reproducers’ lived in environments with low seasonality and high primary productivity and were characterized by high reproductive output (long gestation, large neonates and small litters), short chronology of reproductive events (early age at maturity and short life), small home ranges and high population density. Conservation measures to promote carnivore populations should differ relative to the type of life history, emphasizing adult survival for bet-hedgers and survivors, and juvenile survival for reproducers and competitors.

Long-line fishing mortality poses a significant threat to many large procellariiform seabirds. To date, estimates of impacts have concentrated on lower survival rates, largely ignoring the costs to fecundity resulting from disruption of breeding pairs and skews in sex ratio. A comparative, stochastic, individual-based model was used to investigate these costs for the wandering albatross Diomedea exulans. Ignoring the time taken to replace a lost mate overestimates fecundity by 13–18%, resulting in annual population growth rates (λ) being 0.006–0.007 too high. Long-line mortality exacerbates this cost, which becomes more substantial with increasing demographic skew resulting from female-biased mortality. At moderate levels of long-line mortality (2–4% per year), 80% female-biased mortality reduces fecundity by 9–27% and λ by 0.003–0.010 relative to models with random mortality. Biased sex ratios accumulate and, unlike reduced survival, their impacts on albatross demography persist after long-line mortality ceases. Estimates of the demographic costs of long-line mortality should incorporate individual-level effects, especially where mortality is sex-biased.

Anthropogenic natural habitat transformation presents the single most important threat to global biodiversity. Land cover data, based on Landsat Thematic Mapper (TM) imagery, were used to derive land use information for the Gauteng, Mpumalanga and Northern provinces of South Africa. The assessment integrated land use data with species presence data (15 × 15 minute grid cell resolution) for butterflies, mammals, birds and endemic vascular plants. The objectives of the present study were: (1) to identify areas at a regional scale where there is a possible conflict between biodiversity conservation interests and current land uses; (2) to investigate the influence of incorporating a land use constraint (LUC) into a conservation area selection algorithm, while taking cognizance of the existing reserve system; (3) to investigate the circumstances of species recorded within these conflict areas. Many grid cells identified as species richness hotspots, rarity hotspots or as part of the complementary network selected by the unconstrained algorithm were in reality largely transformed or modified. These areas should thus be avoided when striving to identify a viable conservation network. Although the LUC algorithm selected more grid cells to represent all species, it succeeded in increasing the percentage of natural vegetation within the selected conservation network and highlighted areas where potential conflicts should be thoroughly investigated at a local scale.

We present results from a study of genetic variation in Utah's cougar population. Estimates were based on data for 50 animals at nine microsatellite loci with five individuals sampled for each of ten management units throughout Utah. Levels of variation were moderate (average genetic diversity across populations was estimated to be 0.4687 for all 50 individuals), and comparable with other large mammals. But this level of variation for the microsatellite loci translated into an inbreeding effective population size of only 571 animals, much lower than the current estimates of census sizes of around 2000-3000. A lack of differentiation among the sampled populations across Utah (average Nem = 6.2) indicates that gene flow occurs over a large area. Since cougars are capable of movement beyond the Utah state borders (and certainly across management units), a better understanding of migration rates and patterns of dispersal will be achieved by sampling a much larger geographic region incorporating much of the western USA. Successful management and conservation of this species will then require a far more integrated approach, involving agencies across a number of states, as opposed to current management practices involving individual units within states.

The major nesting areas for loggerhead turtles in Brazil are estimated to produce about 90% female hatchlings on account of their warm temperatures. In the present study, sand temperatures were monitored at the southern cooler end of the nesting range (Comboios, Espiríto Santo): the temperatures were cool enough to produce a far greater proportion of males than at the major beaches further north. Particular beaches may be thermally suited for the production of a particular sex. Protection of rookeries that appear minor in terms of numbers of turtles nesting could be important for the health of a larger population by insuring that there is an appropriate sex ratio. Temperatures were also monitored in a central guarded hatchery, set back from high seas. The hatchery was thermally similar to zones on the beach where turtles commonly lay, indicating that this conservation practice is unlikely to introduce any large distortions of sex ratio on this beach.

Reintroductions of captive-managed animals are a vital tool for the conservation of populations and species extinct in the wild. Because genetic diversity may impact population persistence, the genetic composition of reintroduced and captive populations is critical. For captive-managed species with known pedigrees, individual animals can be selected to create reintroduced populations with specific genetic compositions. Five genetic and demographic strategies for selecting animals were tested on four species. Selection strategies were based on criteria identified in field and theoretical studies. Simulated reintroductions of animals from captive-breeding programmes created a genetic conflict. Among the different strategies, increases in the genetic diversity of one subpopulation were negatively correlated with changes in the genetic diversity of the other subpopulation. For example, the release of genetically over-represented animals was the most beneficial strategy for a captive-breeding programme, but provided the least genetic diversity for the reintroduced population. However, gains and losses in genetic diversity between populations varied with different selection criteria and different population structures. Because captive-breeding histories vary for each species, changes in genetic composition cannot be accurately predicted and no one strategy is universally optimal. Thus, genetic trade-offs must be assessed for each population relative to specific programme goals.

Maximum likelihood mixed stock analysis was used to identify the natal origin of immature loggerhead turtles (Caretta caretta) in a tropical developmental habitat in Caribbean Panamá. Approximately 65-70% of the loggerhead turtles in Chiriquí Lagoon originate from South Florida nesting beaches, and the other 30-35% originate from Mexico. Haplotype frequencies of the Chiriquí Lagoon loggerhead population are significantly different from those observed in the pelagic environment in the eastern Atlantic, and estimated nesting beach contributions to Chiriquí Lagoon are significantly different from values expected if recruitment were based solely on the size of nesting populations. These observations suggest that dispersal of loggerheads into benthic developmental habitats from the pelagic environment is not random. The occurrence of US and Mexican loggerheads in tropical developmental habitats has not been previously recognized. Exploitation and other mortality factors operating in the Caribbean area must be taken into account in demographic models and management plans for these two populations. This exploitation could be particularly important for the small, demographically vulnerable Mexican population and for other small populations for which no genetic data are currently available.

Predicting the threat of extinction aids efficient distribution of conservation resources. This paper utilises a comparative macroecological approach to investigate the threat of extinction in Neotropical birds. Data on ecological variables for 1708 species are analysed using stepwise regression to produce minimum adequate models, first using raw species values and then using independent contrasts (to control for phylogenetic effects). The models differ, suggesting phylogeny has significant effects. The raw species analysis reveals that number of zoogeographical regions occupied, elevational range and utilisation of specialised microhabitats were negatively associated with threat, while minimum elevation and body mass were positively associated, whereas the independent contrasts analysis only identifies zoogeographical regions as important. Confining the analysis to the 582 species restricted to a single zoogeographical region reveals elevational range and number of habitats occupied to be negatively correlated with threat whether the analysis is based on the raw data or on independent contrasts. Analysis of four contrasting zoogeographical regions highlights regional variation in the models. In two Andean regions the threat of extinction declines as the elevation range across which the species occurs increases. In the presence of substantial human populations on high Andean plateaus, a species with a greater elevational range may be more likely to persist at some (relatively) unsettled altitudes. In Central South America, the strongest predictor of threat is minimum elevation of occurrence: species with a lower minimum are less threatened. The minimum elevation result suggests that lowland species experiencing an ecological limit to their minimum elevation (min. elevation >0 m) may be more at risk than those not experiencing such a limit (min. elevation = 0 m). Finally, in southern Amazonia, where there is little altitudinal variation, the only weak predictors of threat are body size, larger species being more threatened, and number of habitats, species occupying more habitats being less threatened. These contrasting results emphasise the importance of undertaking extinction risk analyses at an appropriate geographical scale. Since the models explained only a low percentage of total variance in the data, the effects of human-mediated habitat disturbance across a wide range of habitats may be important.