Populations Of Endangered Species Research Articles

Development of a technique for quarantining Great Artesian Basin springs from colonisation by the invasive fish Eastern Gambusia (Gambusia holbrooki)

SummaryA species recovery project for the endangered fish Red‐finned Blue‐eye (Scaturiginichthys vermeilipinnis) commenced in 2009 at Edgbaston Reserve in central western Queensland. To date, the project has included relocations and control of alien Eastern Gambusia (henceforth Gambusia, Gambusia holbrooki), using the piscicide rotenone. Preventing Gambusia colonising springs where Red‐finned Blue‐eye occur or have been relocated is crucial to the success of the project. As such, this study tested the use of porous silt fences that were installed around five springs from 2012. Results indicate that silt fencing is a suitable barrier material and that provided installed silt fences are serviced regularly, the material is an effective method of quarantining populations of endangered species in isolated aquatic environments. Four of the five installed fences were effective, and maintenance consisted of small repairs at regular intervals (quarterly) followed by replacement after 2 years. As such, silt fencing may have wider application in the conservation of endangered fish and other organisms, particularly in areas where isolated waterbodies occur and where their size renders exclusion fencing a practical recovery action.

Evaluation of a reproductive index for estimating songbird productivity: Case study of the golden-cheeked warbler

It is critically important to determine and understand relationships between endangered species populations and landscape and habitat features to effectively manage and conserve populations and the habitats they rely on. Several recent studies focused on the golden-cheeked warbler (Setophaga chrysoparia), an endangered songbird that breeds exclusively in central Texas, USA, have used a reproductive index to link pairing and breeding success to various factors of interest. However, no field test has evaluated the performance of a reproductive index at estimating productivity of golden-cheeked warblers or similar forest songbirds. We computed reproductive index ranks for 5 observers from multiple plots during 2013 and 2014 and compared these ranks with actual reproductive success determined from territory mapping and nest monitoring of color-banded adults. At the territory level, we found no significant correlation between 84 matched territories delineated by the reproductive index and territories delineated by intensive monitoring. At the plot level, index monitoring underestimated the total number of territorial males, but density from index monitoring was weakly correlated with actual density. We found no significant relationship for pairing success estimated from the reproductive index and actual pairing success, or with breeding success from the reproductive index with nest survival or actual breeding success, when controlling for observer. The reproductive index did not produce reliable estimates of reproductive performance at either the territory or plot level and we recommend intensive monitoring of color-banded individuals when absolute estimates of reproductive success rates or other demographic measures are required, such as in species viability or threat assessments. © 2015 The Wildlife Society.

Engaging active stakeholders in implementation of community‐based conservation: Whooping crane management in Texas, USA

ABSTRACTEngaging a variety of wildlife stakeholders in the implementation of conservation plans is an increasingly frequent activity of wildlife managers. In some cases, stakeholders develop interdependent relationships with a species being managed by the wildlife agency, usually when the species is economically important. We studied the potential for engaging stakeholders in the implementation of community‐based conservation in the winter habitat of the federally endangered whooping crane (Grus americana) to better understand the relationships between stakeholders (including landowners and nongovernmental organizations) and wildlife managers when working with charismatic species that provide local economic value. In May–September 2010, we interviewed 35 Texas individuals interested in crane conservation, and then analyzed transcripts using both a priori and emergent coding techniques. We found that active stakeholders were eager to work with wildlife managers because of the charismatic and economic values they attributed to the whooping crane. We also found that these stakeholders responded positively to agency intervention for the purpose of sharing expert knowledge and providing stakeholders with standing in the dynamically complex management practices surrounding the species and ecosystem. By recognizing the interests of active stakeholders, wildlife managers can expand opportunities for positive public participation in efforts to conserve and restore endangered species populations. They can improve community relations by building on already existing positive perceptions of relationships between humans and wildlife. © 2015 The Authors. Wildlife Society Bulletin published by The Wildlife Society.

Распространение степной гадюки Vipera renardi (Reptilia, Viperidae) в Харьковской области

Изучение современного состояния популяций животных, находящихся под охраной, является неотъемлемым элементом в разработке и построении грамотной стратегии охраны видов. Vipera renardi Christoph, 1861 (Reptilia, Viperidae) включена в Красную книгу Украины, а также в Красную книгу Харьковской области и имеет статус уязвимого вида. В статье приведены обобщенные данные о распространении вида в историческом прошлом, а также о современном состояним популяций в Харьковской области, полученные в результате натурных обследований ранее известных и потенциальных местообитаний. Восемьдесят процентов известных до конца ХХ века популяций степной гадюки в области исчезли. Вероятнее всего, это связано с преобразованием биотопов и, возможно, другими не выясненными причинами, в числе которых отдаленные эффекты фрагментации популяций, загрязнение и побочные результаты применения ядохимикатов. Гадюки практически отсутствуют в северной, лесостепной части области. Северная граница вида в регионе сместилась к югу и сейчас проходит по северной границе степной зоны. На данный момент в Харьковской области достоверно подтверждено пять местообитаний этого вида. Находки в окрестностях пос. Червона Хвыля и пгт. Шевченково приводятся впервые.

Investigation of mortalities associated with Salmonella spp. infection in wildlife on Tiritiri Matangi Island in the Hauraki Gulf of New Zealand

CASE HISTORY: Salmonellosis was suspected as the cause of death in eight wild animals on Tiritiri Matangi Island, in the Hauraki Gulf of New Zealand, between November and September 2011, including three hihi (Notiomystis cincta), a tuatara (Sphenodon punctatus), a masked lapwing (Vanellus miles novaehollandiae), and a saddleback (Philesturnus carunculatus). An outbreak investigation to identify the source and distribution of infection was undertaken over the summer of 2011–2012. CLINICAL AND LABORATORY FINDINGS: Surveillance of five species of forest bird (n=165) in December 2011 returned a single positive result for Salmonella spp. Environmental sampling of 35 key water sources and hihi supplementary feeding stations conducted in December 2011 and March 2012 returned isolates of S. enterica subspecies houtenae and S. enterica serovar Saintpaul from a stream, a dam and a supplementary feeding station. The same serotypes were identified in tissue samples collected from post mortem specimens of the affected birds, and their similarity was confirmed by pulsed-field gel electrophoresis. DIAGNOSIS: Mortality in wildlife associated with infection with S. enterica subspecies houtenae and S. enterica serovar Saintpaul. CLINICAL RELEVANCE: This is the first detection of these Salmonella spp. from wild birds in New Zealand. Our study highlights how active surveillance in response to observed disease emergence (here mortalities) can provide important insight for risk assessment and management within populations of endangered species and inform risk assessment in translocation planning.

FROM HARVESTING TO NONHARVESTING UTILITY: AN OPTIMAL CONTROL APPROACH TO SPECIES CONSERVATION

AbstractThe purpose of this paper is to retrace the evolution of mathematical models focused on relation and interaction between economic growth, sustainable development, and natural environment conservation. First, generic defensive expenditures are introduced into a common‐property harvesting model in order to favor the species growth. Second, a transition model comprising both harvesting and nonharvesting values of wildlife biological species emerges. The latter gives rise to a group of purely nonharvesting models where anthropic activities and economic growth may have positive or negative impact on the natural evolution of wildlife species. Several scholars have proved that optimal strategies that are relatively good for harvesting purposes are not simply “transferrable” to the context of conservation of wildlife biological species with no harvesting value. In addition, the existence of optimal policies for long‐term conservation of all biological species (with or without harvesting value) cannot be guaranteed without having relatively large species populations at the initial time. Therefore, all such strategies are incapable of enhancing the scarce populations of endangered species and, therefore, cannot save these species from eventual (local) extinction. As an alternative, policymakers may soon be compelled to design and implement short‐term defensive actions aimed at recovery and enhancement of endangered wildlife species.

Predicting extinction or explosion in a Galton–Watson branching process with power series offspring distribution

Extinction is certain in a Galton–Watson (GW) branching process if the offspring mean μ≤1, whereas explosion is possible but not certain if μ>1. Discriminating between these two possibilities is a well-studied hypothesis-testing problem. However, deciding whether extinction or explosion will occur for the current realization of the process is a prediction problem. This can be formulated as a different testing problem by considering the conditional distributions of the process given extinction and explosion respectively. For power series offspring distributions, fixed-sample and sequential parametric tests are presented for the prediction problem and illustrated with data on the spread of epidemics and the populations of endangered species.

Conflicting rates of increase in the sperm whale population of the eastern Caribbean: positive observed rates do not reflect a healthy population

Observed rates of increase calculated from trends in the numbers of animals present in a population should generally agree with those estimated from life-history data. However, for a small population of individually identified sperm whales Physeter macrocephalus occupying the waters of the eastern Caribbean there is a discrepancy. Using a mark-recapture analysis that included heterogeneity in identification, the population, numbering about 156 adults (95% CI 126−195) in 1998, has been increasing at 3.4% yr −1 (95% CI: 1.0−5.7% yr −1 ). However, a 2-stage matrix population model including unweaned calves and adults (and excluding mature males), whose parameters were estimated directly from empirical data, gave a projected rate of increase of −2.7% yr −1 (95% CI: −5.4 to −0.4% yr −1 ). This estimate is primarily sensitive to calculated adult mortality. The discrepancy between the observed and projected rates of increase for this popula- tion may be explained by a high, probably anthropogenic, mortality of sperm whales in the east- ern Caribbean, coupled with immigration from surrounding regions, so the area becomes an attractive sink (ecological trap). The analysis emphasizes the fragility of sperm whale populations. More generally, our analysis of this population shows that a positive observed rate of increase is not necessarily a sign of a healthy population. This case study highlights the importance of analysing populations of endangered species using multiple methodologies and with a solid base of individual-level empirical data based on longitudinal monitoring.

Male reproductive success is correlated with testosterone in the eastern black rhinoceros (Diceros bicornis michaeli)

Among natural populations of polygynous species, males often vary in their lifetime reproductive success. However, in managed populations of endangered species, either in situ or as part of captive breeding programmes, it is important to understand why differences in reproductive success occur. The European captive population of the critically endangered eastern black rhinoceros is currently under-performing relative to their wild counterparts, with low reproductive output and high reproductive skew limiting growth and genetic diversity. To investigate why over 40% of captive males fail to breed, faecal samples were collected weekly from 23 males at 12 institutions across Europe for 4–32months. Testosterone metabolite concentration was compared between proven and non-proven males and a number of intrinsic and extrinsic factors that could influence reproductive success were also investigated. Males that sired within the last 3½years had significantly higher androgen concentrations than non-proven males, and average testosterone was positively correlated with the number of offspring sired per year spent in the reproductive age class. Proven and non-proven males did not differ in their body condition, or in average faecal glucocorticoid concentration. Differences in individual temperament were associated with adrenal activity, but did not correlate with reproductive category. Highest testosterone concentrations were observed in proven males that were housed with females during oestrus, and lowest concentrations in non-proven females not housed with females at all during the study period. Further work is necessary to determine whether proven males had higher testosterone due to underlying differences associated with quality, or whether external stimuli such as access to females could influence testosterone concentration and increase a male’s chances of becoming a successful breeder.

First record of an introduced population of the southern lineage of white-clawed crayfish (Austropotamobius ‘italicus’) north of the Alps

Elucidating the status of populations of endangered species of unclear origin may have important implications for conservation management. In September 2013, a population of white-clawed crayfish was discovered outside of the native range in a small artificial lake in the River Neckar catchment in southwestern Germany. White-clawed crayfish comprise two distinct lineages of yet unresolved taxonomic status, of which only the western lineage (Austropotamobius pallipes s. str.) is native to Germany. To clarify the taxonomic identity and origin of the newly discovered population, we evaluated diagnostic morphological characters and sequences of two mitochondrial genes (for 16S rRNA and cytochrome c oxidase subunit I) from two crayfish specimens. Both analyses concordantly assigned the crayfish to the southern lineage (A. ‘italicus ’), with the closest matching haplotypes originating from northwestern Italy, southeastern Switzerland, and Lake Plansee in Austria, where an abundant introduced population of this lineage is present. The artificial lake in Germany was reportedly stocked with freshwater mussels from this Austrian lake. It thus appears likely that A. ‘italicus ’ was introduced intentionally or accidentally during the process. Austropotamobius ‘italicus ’ does not naturally occur north of the Alps and thus represents a non-native taxon for Germany, a fact to be considered in its management.

Breeding ecology and success of a reintroduced population of the endangered Crested Ibis Nipponia nippon

SummaryReintroduction projects usually attempt to re-establish a self-sustaining population of endangered species within their historical ranges through the release of captive-bred individuals into the wild. We studied the breeding biology and nesting success of a reintroduced population of Crested Ibis Nipponia nippon in Ningshan County on the south slope of the Qinling Mountains of Shaannxi Province, China. From May 2007 to October 2011, 56 captive-bred individuals, composed of 26 females and 30 males, were released into the area and monitored using radio-telemetry. The average age of individuals at release was 5.2 ± 2.5 years for females and 6.4 ± 2.9 years for males. Mean clutch size was 3.14±1.06 (range 1-5). Mean number of fledglings per active nest was 1.57 ± 1.03 and mean number of fledglings per successful nest was 2.00 ± 0.87. Most of the fledglings survived to complete their post-fledging dispersal. Mean annual survival rate was 0.552 ± 0.064 for all released birds, 0.815 ± 0.054 for breeders, and 0.515 ± 0.058 for first year fledglings. The average number of young produced/year/pair was 1.57 ± 1.03 and the growth rate (λ) of the reintroduced population was 1.2193. We confirmed that starvation and predation by King Rat Snake Elaphe carinata were the main causes of death of released individuals, nestlings and fledglings. This is the first attempt to reintroduce captive-bred Crested Ibis to former natural habitat. The ability of captive-bred ibis to survive and breed successfully bodes well for future releases of this and other endangered species.

Effects of temperature and surface water availability on spatiotemporal dynamics of stream salamanders using pattern-oriented modelling

Ecological models are powerful tools for generating predictions about the viability of populations of endangered species, especially in landscapes where they may be subject to complex, cross-scale disturbances. Spatially explicit, individual-based approaches are particularly promising due to their ability to simulate the effect of landscape level changes in habitat on individual-level behaviour, thus predicting possible emergent responses from the bottom up. We apply this approach to modelling the movement behaviour and the complex life cycles of two species of stream-dwelling salamanders (the Allegheny Mountain Dusky Salamander, Desmognathus ochrophaeus, and the Northern Spring Salamander, Gyrinophilus porphyriticus) in response to a spatially and temporally varying environment. Despite the poor state of ecological knowledge about these species, our model provides reasonable predictions about life cycle, as well as the density and distribution of salamanders. When tested with a dynamic, drought prone environment, the model predicts viability levels that are biologically plausible. By simulating the cross-scale interactions between organisms and their environment, individual-based models such as we have developed here provide a new tool for in silico investigations of the expected impacts of varying landscape scenarios and environmental changes.

Outstanding challenges for urban conservation research and action

Researchers, advocates and policymakers have proposed urban conservation as an emerging, integrative discipline that can contribute to sustainable cities by delivering co-benefits to human and non-human components of biodiversity. Given the recent growth in biodiversity-friendly designs and management schemes, there is an urgent need for a synthesis of this fragmented research base to inform planners and decision-makers. We conducted a systematic multidisciplinary literature review (787 papers) and found that the importance of urban areas for general conservation is not convincingly supported by empirical research. Only few studies demonstrated that cities can directly contribute to conservation efforts, by hosting viable populations of rare or endangered species, or by providing green corridors for the passage of natural populations. From a social perspective, while several studies demonstrated that green infrastructure could provide services for people (notably cultural services), only few studies explored the role of species diversity per se. Our review also shows strong geographical, location and taxonomic biases in urban biodiversity conservation research that make generalisations difficult. It is a disturbing paradox that while research in urban biodiversity conservation is rising exponentially, the main motivations for conserving urban biodiversity remain largely untested and unproven. We thus propose a framework for promoting integrative urban conservation research to bridge those gaps. Together, these findings warn against expanding cities under green planning and call for enhancing biodiversity experience by improving the quality of existing green spaces throughout the entire urban matrix. We provide a set of recommendations for practitioners and decision-makers to continue action.

Diversidad, composición y estructura de la vegetación en un agropaisaje ganadero en Matiguás, Nicaragua

The diversity, composition and structure of vegetation in a cattle landscape in Matiguás, Nicaragua was characterized, and the floristic and structural differences of six types of habitats (secondary forests, riparian forests, charrales, live fences and pastures with high and low tree cover) were compared. A total of 3 949 trees of 180 species and 52 families were recorded. Forty six percent of the total trees reported for the landscape were represented by Guazuma ulmifolia (18.5%), Bursera simaruha (13.2%), Tabebuia rosea (6.3%), Enterolobium cyclocarpum (4.2%) and Albizia saman (3.4%). Many of the dominant species in the landscape were typical of open and disturbed areas. There were significant differences between the different habitats in the patterns of tree species richness, abundance, diversity, structure and floristic composition. The riparian forests had greater tree richness (p=0.0001) and diversity (p=0.0009) than other habitats. The floristic composition varied across habitats. with pairs of habitats sharing between 18.4 and 51.6% of the same tree species, and with clear differences in composition between the forested (riparian and secondary forests) and agricultural habitats. Of the habitats studied, the riparian forests and secondary forests seem to have greatest value for the conservation of the flora in the agropaisaje because they have the greatest species richness, and maintain small populations of endangered species. On the basis of the study, we recommend including agricultural landscapes in strategies to conserve tree diversity and suggest measures to ensure the maintenance of tree diversity in the Matiguas landscape.

Loss of genetic variation in declining populations of Aricia artaxerxes in Northern Hungary

Rapid decline of population size often gives rise to loss of genetic variation and may result in a reduction in fitness. It is, therefore, essential to detect past demographic changes in populations of endangered species. Aricia artaxerxes occurs in two regions of Northern Hungary: Bukk Mts. and the Aggtelek Karst region. The species prefers short-grass habitats, which are subject to succession. Due to climatic differences between the two regions succession is more rapid in the Bukk plateau resulting in the decline and isolation of A. artaxerxes populations there. In contrast, most populations have remained rather large and stable in the Karst region. This situation provides an excellent possibility to compare the genetic composition of stable and declining populations. A. artaxerxes was collected in four populations of the Bukk Mountains and in ten in the Aggtelek Karst region in 2002 and 2005. We analysed 19 polymorphic allozyme loci in all samples. The results revealed an extremely high level of enzyme polymorphism in A. artaxerxes. Most parameters of polymorphism proved to be significantly higher in the Karst region compared to the Bukk. The shape of the distribution of alleles among the frequency classes indicated the effect of bottleneck in three Bukk and one Karst population. Though heterozygote excess was only significant in one Bukk population a tendency was observed for higher values of standardised heterozygote excess in those populations that had a typical bottleneck distribution of alleles. Our results clearly demonstrated that those populations/subpopulations that compose a network with intense migration are able to maintain their genetic diversity in a long run, while the isolated small populations of the Bukk plateau have lost a sizeable part of their variation.

Habitat selection by Eld's deer following relocation to a patchy landscape.

An emerging issue in wildlife conservation is the re-establishment of viable populations of endangered species in suitable habitats. Here, we studied habitat selection by a population of Hainan Eld’s deer (Cervus eldi) relocated to a patchy landscape of farmland and forest. Hainan Eld’s deer were pushed to the brink of extinction in the 1970s, but their population expanded rapidly from 26 to more than 1000 individuals by 2003 through effective reserve protection. As part of a wider relocation and population management strategy, 131 deer were removed from the reserve and reintroduced into a farmland-forest landscape in 2005. Habitat use under a context of human disturbance was surveyed by monitoring 19 radio-collared animals. The majority of deer locations (77%) were within 0.6–2 km of villages. Annual home ranges of these collared deer averaged 725 ha (SD 436), which was 55% of the size of the reserve from which they had originated. The annual home ranges contained 54% shrub-grassland, 26% forest and 15% farmland. The relocated deer population selected landscape comprising slash-and-burn agriculture and forest, and avoided both intensively farmed areas and areas containing only forest. Within the selected landscape, deer preferred swiddens and shrub-grasslands. Forests above 300 m in elevation were avoided, whereas forests below 300 m in elevation were overrepresented during the dry season and randomly used during the wet season. Our findings show that reintroduced deer can utilize disturbed habitats, and further demonstrate that subsistence agroforest ecosystems have the capacity to sustain endangered ungulates.

Density-dependent regulation of the critically endangered black rhinoceros population in Ithala Game Reserve, South Africa

Ensuring the persistence of populations of endangered species requires an understanding of, and response to, the causes of population declines. Species occurring in small populations are vulnerable to stochastic problems that are environmental, demographic, or genetic in nature and can reduce survival as much as the deterministic threats of habitat degradation. Critically endangered black rhinoceros (Diceros bicornis) populations declined throughout Africa since 1960, with numbers steadily increasing at a continental level, but remaining lower than three generations ago. However, size, demographics, trends, and factors affecting these, are poorly known. We used 18 years (1990–2008) of long-term sightings data from Ithala Game Reserve, KwaZulu-Natal, South Africa, to determine population estimates, growth rate and fecundity over time, as well as sex and age structure and age-specific probabilities of survival. Calf survivorship between the ages of 0 and 1 year was 74% for females and 94% for males. Age-specific survivorship for both sexes was significantly higher from yearling to subadult age-classes (1–6 years) than for adults (7–30 years). The most frequent cause of mortality was attributed to unknown causes while fighting injuries was recorded as the second most common cause of mortality, particularly among subadult and adult males. There was no significant difference in the sex ratios at birth, although the proportion of females in the population was 0.58. There was strong evidence for density-dependent regulation, with density in conception year a key driver of population performance (birth rate). The population does not appear to be at ecological carrying capacity; however, social effects are delaying conception. To mitigate density-dependent social effects, we recommend an adaptive management strategy of pre-selecting individuals for removal from the reserve, so as to maintain stability in the social organization of the population.

First parasitological survey of Endangered Bornean elephants Elephas maximus borneensis

Relatively few studies have been carried out on the parasites of free-ranging wild animal species, which has led to a lack of baseline parasitological data. This is a concern because endoparasites can have an important influence on fitness and survival, particularly in small populations of endangered species. This field study is the first parasitological survey of Endangered Bornean elephants Elephas maximus borneensis. Using a special modification of the McMaster method, trematode, cestode and nematode ova were identified in the faeces of wild Bornean elephants in 2 key range areas in Sabah, Malaysian Borneo: the Tabin Wildlife Reserve and the Lower Kinabatangan Wildlife Sanctuary. Preliminary comparisons between the sites suggest that prevalence, load and diversity vary between the two, leading to hypotheses on host, parasite and environmental factors which may affect endoparasite infection dynamics in wild Bornean elephants. This study provides an initial catalogue of parasite types in the Bornean elephant and reports on endoparasite prevalence and load, valuable baseline data for future research.

The Promise and Practicality of Population Genomics Research with Endangered Species

Recent technological advances have dramatically reduced the cost of DNA sequencing. In addition, these methods require lower DNA quantities and qualities than did the previous generation of molecular techniques. As a result, genomic-scale studies of natural populations of endangered species, including those using noninvasively collected samples, are increasingly feasible. Such studies have the potential to advance our understanding of behavior, demography, evolutionary ecology, biogeography, and population history, and to contribute to the prioritization of conservation efforts. I point to a number of salient examples. However, there are also some current limitations and challenges associated with this scale of population genomics research in nonhuman, nonmodel species. Here, I describe the practicalities of the present state of this research while providing what is intended to be a straightforward walkthrough of the technology and methods involved.

Demographic variation, reintroduction, and persistence of an island duck (Anas laysanensis )

Population variation in life history can be important for predicting successful establishment and persistence of reintroduced populations of endangered species. The Laysan duck (Anas laysanensis) is an endangered bird native to the Hawaiian Archipelago that was extirpated from most islands after the introduction of mammalian predators. Laysan ducks were restricted to a single remote island, Laysan Island (4.1 km2), for nearly 150 years. Since the species is not known to disperse between distant Hawaiian Islands today, 42 wild birds from Laysan Island were translocated to another mammalian predator-free low-lying atoll (Midway Atoll; 6.0 km2) to reduce extinction risk. We explored how variation in demography influences establishment and longer-term retention of genetic diversity (rare alleles) for reintroductions of this species. We observed dramatic differences in population growth between the source (λ = 1.18) and reintroduced (λ = 3.28) population. The number of eggs hatched at Midway Atoll was greater than at Laysan Island, however, we found no difference in hatching success (proportion of clutch hatched) between populations. Adult females produced 3 times as many fledglings per breeding year on Midway Atoll compared to Laysan Island. We estimated population abundance of both populations until 2010 and applied a Gompertz model with a Bayesian approach to infer density dependence, process variation, observation error, and carrying capacity for the Laysan Island and Midway Atoll populations. The carrying capacity from the Gompertz model for Midway Atoll (K = 883 ± 210 SD) was estimated to be greater than that of Laysan Island (K = 598 ± 76 SD). Translocations with small numbers of founders and no immigration can create population bottlenecks, leading to loss of genetic variation over time, and potentially reducing the reintroduced population's viability or its potential to serve as a source for future translocations. Therefore, we also assessed the probability of retaining rare alleles in an isolated reintroduced Laysan duck population using life history parameters observed from the Laysan Island and Midway Atoll populations; we concluded that additional founders are needed under scenarios using demographic estimates from both Laysan Island and Midway Atoll to retain either 90% or 95% of source population genetic diversity. © 2013 The Wildlife Society.