Dissecting the Shared Genetic Architecture of Suicide Attempt, Psychiatric Disorders, and Known Risk Factors

Background Suicide is a leading cause of death worldwide, and nonfatal suicide attempts, which occur far more frequently, are a major source of disability and social and economic burden. Both have substantial genetic etiology, which is partially shared and partially distinct from that of related psychiatric disorders. Methods We conducted a genome-wide association study (GWAS) of 29,782 suicide attempt (SA) cases and 519,961 controls in the International Suicide Genetics Consortium (ISGC). The GWAS of SA was conditioned on psychiatric disorders using GWAS summary statistics via multitrait-based conditional and joint analysis, to remove genetic effects on SA mediated by psychiatric disorders. We investigated the shared and divergent genetic architectures of SA, psychiatric disorders, and other known risk factors. Results Two loci reached genome-wide significance for SA: the major histocompatibility complex and an intergenic locus on chromosome 7, the latter of which remained associated with SA after conditioning on psychiatric disorders and replicated in an independent cohort from the Million Veteran Program. This locus has been implicated in risk-taking behavior, smoking, and insomnia. SA showed strong genetic correlation with psychiatric disorders, particularly major depression, and also with smoking, pain, risk-taking behavior, sleep disturbances, lower educational attainment, reproductive traits, lower socioeconomic status, and poorer general health. After conditioning on psychiatric disorders, the genetic correlations between SA and psychiatric disorders decreased, whereas those with nonpsychiatric traits remained largely unchanged. Conclusions Our results identify a risk locus that contributes more strongly to SA than other phenotypes and suggest a shared underlying biology between SA and known risk factors that is not mediated by psychiatric disorders.Peer reviewe

The Effects of Prey Availability on the Numerical Response of Wading Birds

Reduced prey availability has emerged as a primary hypothesis to explain population constraints on wading birds in numerous wetlands around the world. However, there is almost no understanding of which component of prey availability (i.e., prey density or vulnerability of prey to capture) is affecting populations and whether the relative effects of each component differ among species. In this study, I manipulated prey density and water depth (i.e., prey availability) in 12 0.2-ha ponds to determine their relative effects on the numeric response of eight species of free-ranging wading birds (White Ibis, Eu- docimus albus; Wood Stork, Mycteria americana; Snowy Egret, Egretta thula; Glossy Ibis, Plegadis falcinellus; Great Egret, Ardea alba; Tricolored Heron, Egretta tricolor; Great Blue Heron, Ardea herodias; and Little Blue Heron, Egretta caerulea). The experiment was conducted in a constructed wetland adjacent to, and west of, the northern tip of the remnant Everglades, in Palm Beach County, Florida, USA. Each pond was set to a water depth of 10 cm, 19 cm, or 28 cm, and was stocked with golden shiners (Notemigonus crysoleucas) at a density of either 3 fish/m2 or 10 fish/m2. Total bird use (all treatments pooled) increased from day 1 (day after stocking) to day 6, stabilized for several days at -280 birds, and then decreased until day 16, when bird use nearly ceased. Fish were depleted most rapidly in the shallow treatment and least rapidly in the deep treatment. The giving-up-density (GUD) of prey increased with increasing water depth. There was no significant difference among species in the slope of that relationship; however, a visual inspection of the data showed that differences in GUDs were becoming more apparent in the deepest treatment. At that depth, the White Ibis, Wood Stork, and Snowy Egret had higher GUDs than did the Glossy Ibis, Great Egret, Tricolored Heron, Great Blue Heron, and Little Blue Heron. Also, the first three species were affected significantly by both prey density and water depth, whereas the latter five species showed a decidedly weaker response to one or the other component of prey availability. The first three species were more abundant in the shallow treatments and the high prey density treatments, and they abandoned the study site before other species reached their maximum density. The feeding strategy of the first group appeared to be one of searching for new high-quality food patches rather than staying and exploiting food patches that were declining in quality. Species that employed a searching strategy also have shown the most severe population declines, suggesting that factors affecting bird density at feeding sites may also have affected population size

The role of wildlife science in wetland ecosystem restoration: Lessons from the Everglades

There has been little discussion of how and when to integrate wildlife science into ecological restoration projects. The recent emergence of wetland ecosystem restoration offers an opportunity to use wildlife science to increase the probability of a project being successful. This paper traces the evolution of wetland ecosystem restoration in North America and proposes three roles for wildlife science in wetland ecosystem restoration: (1) contribute to conceptual ecosystem models, (2) develop quantitative performance measures and restoration targets that track the progress of restoration, and (3) achieve social feasibility by sustaining long-term public support for a project. The extensive knowledge base for many species of wildlife makes them especially useful for contributing to conceptual ecosystem models. Wildlife species are often the subject of long-term monitoring and research because they have commercial value, are conspicuous, or have aesthetic appeal. Wildlife parameters can be good performance measures for large-scale restoration projects because some species integrate information over large spatial scales and are long- lived. Parameters associated with threatened or endangered wildlife species should get special consideration as performance measures because the information will meet multiple needs rather than just those of the conceptual ecosystem model. Finally, wetland ecosystem restoration projects need to sustain funding over decades to ensure the restored system is self-sustaining. Wildlife are a valued resource that can help achieve the social feasibility of a project by providing a way to communicate complex science in terms that society understands and value

CONSERVATION BIOLOGY AND THE EVOLUTION OF A LAND ETHIC

Volume: 26Start Page: 179End Page: 18

Multiple Nest-Tending Behavior in an Adult Female White Ibis

A non-breeding adult female White Ibis (Eudocimus albus) was observed tending multiple nests during the 2006 wading bird breeding season in the Florida Everglades. This is the first known case of adult multiple nest-attending breeding behavior documented for the Ciconiiformes order

Dietary flexibility of Wood Storks in response to human-induced rapid environmental change

Human-induced rapid environmental change (HIREC) has altered landscape processes and negatively impacted many species globally. Some of the most dramatic changes have been in wetlands where flows have been disrupted, and new wetlands have been created to retain runoff. In response to disrupted natural wetland conditions, Wood Stork (Mycteria americana) populations in South Florida have significantly declined over the past several decades. Despite the well-documented sensitivity of Wood Storks to natural wetland conditions, Wood Storks are often observed foraging in roadside created wetlands; however, the availability of prey in created wetlands is currently unknown. We sampled natural and created wetlands to determine aquatic fauna available for foraging Wood Storks. To determine prey use, we collected food boluses from Wood Storks in both natural wetland and urban landscapes. Historical studies found nonnative fish were absent in Wood Stork diet prior to the dominance of created wetlands in the landscape; however, we found nonnative fish frequently in both created wetlands and boluses. Furthermore, urban nesting Wood Storks consumed large-bodied prey species that were more characteristic of created wetlands whereas Wood Storks nesting in natural wetlands consumed large-bodied prey more characteristic of natural wetlands. Overall, Wood Storks consumed prey that were more similar to the fish community in created wetlands than those in natural wetlands. These dietary patterns suggest that Wood Storks have behavioral plasticity in both foraging habitat and prey use to cope with HIREC. Conservation efforts for species existing in both natural and urban habitats should consider the importance of novel prey and foraging habitats, as they may assist in sustaining populations in a rapidly changing world

Anthropogenic food in the diet of the Sacred Ibis, Threskiornis aethiopicus, a non-native wading bird in southeastern Florida, USA

The Sacred Ibis ( Threskiornis aethiopicus ), is native to sub-Saharan Africa. A small breeding population in southeastern Florida, USA, was established in 1992 and expanded to surrounding natural areas until 2008 when an eradication program was initiated. This study investigated the degree to which the population of Sacred Ibis in South Florida consumes food items derived from human activities which may have contributed to its population expansion. Body measurements, the first such data for this species in North America, were obtained for eight adult males and five adult females. The contents of the esophageal tract and gizzards were used to classify ibis diets (N = 22) as being of anthropogenic origin (derived from human activities) if they contained cheese, meat, paper pulp, and/or pellet meal. The diet of the Sacred Ibis was comprised of predominately anthropogenic food items (58% of the cumulative biomass). Ibises with anthropogenic food items found in their diet consumed more biomass (26.99g ± SE 5.35g) than did birds that contained only natural food items in their diet (8.74g ± SE 2.21g). Natural diets, on average, contained a significantly greater percent vegetative matter (63% ± SE 12%) than did anthropogenic diets (8% ± SE 3%). Novel organic and inorganic items found in anthropogenic diets included bacon, glass, hot dog, pellet meal, and plastic. A cluster analysis revealed that some ibises used anthropogenic food as a primary food source whereas others used it as a supplement to natural food items. This study suggests that human food resources, and the habitats that contain them, may have the ability to support this species’ establishment. Further investigation, of ecologically similar species, may elucidate linkages between human food resources in urbanized areas and impacts in nearby natural habitats

Potential for successful population establishment of the nonindigenous sacred ibis in the Florida Everglades

The nonindigenous sacred ibis (Threskiornis aethiopicus) was first discovered breeding in the Florida Everglades in 2005 in the Arthur R. Marshall Loxahatchee National Wildlife Refuge. Prior to this, sacred ibises were seen periodically throughout South Florida since the mid 1990s, with occasional confirmed breeding occurrences in Miami-Dade and Palm Beach counties. We used a logistic regression model developed by Allen (Biol Invasions 8:491–500, 2006) to predict the probability of successful establishment of sacred ibis in the Florida Everglades ecosystem. Empirical data collected from several sacred ibis nests and chicks were used to validate those findings. The probability of successful establishment was estimated to be 73%. The physiological condition of nestlings suggested that this species was able to fledge chicks in good condition, thus adding to the potential to increase their breeding population. Exponential population growth rates and expanding distribution of the nonindigenous sacred ibis in France demonstrate this species’ potential for becoming invasive in Florida. We suggest that the most prudent and effective management strategy is eradication of the few pioneering individuals that are nesting in the Everglades as well as the urban source population