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Animal translocations commonly fail due to predation after release, especially if animals are reared in human care, away from natural predation pressure. Anti-predator training can be a useful tool for combating the predator naivety of released animals, but its effective implementation requires attention to numerous details. We present the step-by-step development of an anti-predator training regime, tailored to the critically endangered `alalā (Corvus hawaiiensis). `Alalā are the last remaining corvid species of the Hawaiian islands, and historically the level of predation they experienced from the Hawaiian hawk, `io (Buteo solitarius) is unclear. However, one factor thought to compromise outcomes of earlier attempts to reintroduce `alalā in the 1990′s was predation by `io, motivating the development of anti-predator training for recent `alalā releases. We documented evidence for what appears to be competent anti-predator behavior in conservation-bred `alalā, with a range of behavioral strategies for coping with `io observed during a series of controlled presentations of `io and `io-related stimuli. These behavioral responses included vigilance, alarm calling, and mobbing during experimental trials conducted in release training aviaries. Our results did not conclusively establish that anti-predator learning occurred as a result of the training, or that the training produced enhanced survival. However, following release, `io-`alalā encounters were observed on more than 35 occasions, and `alalā responses mirrored those observed pre-release, including the first ever recorded mobbing interactions by juvenile flocks of `alalā in the wild. While it is unclear the extent to which training encouraged these species-appropriate anti-predator responses, their occurrence suggests that the `alalā has retained and can express defensive behavioral strategies. By documenting the design process, training execution and behavioral outcomes in `alalā, we highlight details that other reintroduction programs may need to consider when preparing animals for reintroduction alongside natural predators.

Plant–animal interactions are key to sustaining whole communities and ecosystem function. However, their complexity may limit our understanding of the underlying mechanisms and the species involved. The ecological effects of epizoochory remain little known compared to other seed dispersal mechanisms given the few vectors identified. In addition, epizoochory is mostly considered non-mutualistic since dispersers do not obtain nutritional rewards. Here, we show a widespread but unknown mutualistic interaction between parrots and plants through epizoochory. Combining our observations with photos from web-sources, we recorded nearly 2000 epizoochory events in 48 countries across five continents, involving 116 parrot species and nearly 100 plant species from 35 families, including both native and non-native species. The viscid pulp of fleshy fruits and anemochorous structures facilitate the adherence of tiny seeds (mean 3.7 2.56 mm) on the surface of parrots while feeding, allowing the dispersion of these seeds over long distances (mean = 118.5 m). This parrot–plant mutualism could be important in ecosystem functioning across a wide diversity of environments, also facilitating the spread of exotic plants. Future studies should include parrots for a better understanding of plant dispersal processes and for developing effective conservation actions against habitat loss and biological invasions

While most of the knowledge on invasive species focuses on their impacts, little is known about their potential positive effects on other species. Invasive ecosystem engineers can disrupt recipient environments; however, they may also facilitate access to novel resources for native species. The monk parakeet (Myiopsitta monachus) is a worldwide invader and the only parrot that builds its own communal nests, which can be used by other species. However, the ecological effects of these interspecific interactions are barely known. We compared the role of the monk parakeet as a nest-site facilitator in different rural and urban areas, both invaded and native, across three continents and eight breeding seasons. A total of 2690 nests from 42 tenant species, mostly cavity-nesting birds, were recorded in 26% of 2595 monk parakeet nests. Rural and invaded areas showed the highest abundance and richness of tenant species. Multispecies communal nests triggered interspecific aggression between the monk parakeet host and its tenants, but also a cooperative defense against predators. Despite the positive effects for native species, monk parakeets also facilitate nesting opportunities to other non-native species and may also transmit diseases to tenants, highlighting the complexity of biotic interactions in biological invasions., This research was funded by Severo Ochoa Program (SVP-2014-068732), Action COST “ParrotNet” (ES1304), Loro Parque Fundación (PP-146-2018-1), and Ministry of Economy and Competitiveness, Spanish Research Council (CGL-2016-79568-C3-3-P).

The family Psittacidae is comprised of over 400 species, an ever-increasing number of which are considered threatened with extinction. In recent decades, conservation strategies for these species have increasingly employed reintroduction as a technique for reestablishing populations in previously extirpated areas. Because most Psittacines are highly social and flocking species, reintroduction efforts may face the numerical and methodological challenge of overcoming initial Allee effects during the critical establishment phase of the reintroduction. These Allee effects can result from failures to achieve adequate site fidelity, survival and flock cohesion of released individuals, thus jeopardizing the success of the reintroduction. Over the past 20 years, efforts to reestablish and augment populations of the critically endangered Puerto Rican parrot (Amazona vittata) have periodically faced the challenge of apparent Allee effects. These challenges have been mitigated via a novel release strategy designed to promote site fidelity, flock cohesion and rapid reproduction of released parrots. Efforts to date have resulted in not only the reestablishment of an additional wild population in Puerto Rico, but also the reestablishment of the species in the El Yunque National Forest following its extirpation there by the Category 5 hurricane Maria in 2017. This promising release strategy has potential applicability in reintroductions of other psittacines and highly social species in general.

Accurately identifying threats to global biodiversity is the first step towards effectively countering or ameliorating them. However, such threats are usually only qualitatively categorized, without any comparative quantitative assessment of threat levels either within or across ecosystems. As part of recent efforts in Papua New Guinea to develop a long-term strategic plan for reducing threats to biodiversity at the national level, we developed a novel and quantitative method for not only assessing relative effects of specific biodiversity threats across multiple ecosystems, but also identifying and prioritizing conservation actions best suited for countering identified threats. To do so, we used an abbreviated quantitative SWOT (Strengths, Weaknesses, Opportunities, Threats) analysis and multivariate cluster analysis to identify the most significant threats to biodiversity in Papua New Guinea. Of 27 specific threats identified, there were nine major threats (each &gt, 5% of total) which accounted for approximately 72% of the total quantified biodiversity threat in Papua New Guinea. We then used the information to identify underlying crosscutting threat drivers and specific conservation actions that would have the greatest probability of reducing biodiversity threats across multiple ecosystem realms. We categorized recommended actions within three strategic categories, with actions within each category targeting two different spatial scales. Our integrated quantitative approach to identifying and addressing biodiversity threats is intuitive, comprehensive, repeatable and computationally simple. Analyses of this nature can be invaluable for avoiding not only wasted resources, but also ineffective measures for conserving biodiversity.

Recent decades have seen increasing use and importance of translocations and reintroductions as tools for species’ conservation and ecological restorations. Most such efforts face substantial logistical complexities and high costs, both biological and financial. These and other challenges have contributed to numerous failures or partial successes of reintroductions, a trend which has improved little over time. Given the negative ramifications of reintroduction failures, practitioners have adopted or developed numerous analytical and procedural methods in efforts to promote successful outcomes. However, many such methods are often ad hoc or taxon-specific, particularly regarding the evaluation and selection of reintroduction areas and sites. Despite the recognized importance of this phase of reintroduction planning, there is to date no comprehensive methodology for selecting suitable reintroduction sites. We describe in detail the application of quantitative SWOT (Strengths, Weaknesses, Opportunities, Threats) analysis for objectively evaluating candidate reintroduction areas or sites, and how results of this analysis are used for identifying the most effective and efficient management actions for promoting reintroduction success. We use examples drawn from recent reintroduction plans for three avian species in Puerto Rico (1) and Brazil (2) to illustrate specific methodologies used as well as the results obtained and their application to the reintroduction planning and implementation process. From our findings, quantitative SWOT analysis is a simple, versatile, repeatable and intuitive method for reintroduction area and site selection. The method also provides a valuable mechanism for evaluating and prioritizing management actions relative to their efficiency and effectiveness for achieving reintroduction objectives.

Psittaciformes (parrots, cockatoos) are among the most endangered birds, with 31% of Neotropical species under threat. The drivers of this situation appear to be manifold and mainly of anthropogenic origin. However, this assessment is based on the last extensive consultation about the conservation situation of parrots carried out in the 1990s. Given the rapid development of anthropogenic threats, updated data are needed to strategize conservation actions. Using a population approach, we addressed this need through a wide-ranging consultation involving biologists, wildlife managers, government agencies and non-governmental conservation organizations. We gathered up-to-date information on threats affecting 192 populations of 96 Neotropical parrot species across 21 countries. Moreover, we investigated associations among current threats and population trends. Many populations were affected by multiple threats. Agriculture, Capture for the Pet Trade, Logging, each of them affected > 55% of the populations, suggesting a higher degree of risk than previously thought. In contrast to previous studies at the species level, our study showed that the threat most closely associated with decreasing population trends is now Capture for the local Pet Trade. Other threats associated with decreasing populations include Small-holder Farming, Rural Population Pressure, Nest Destruction by Poachers, Agro-industry Grazing, Small-holder Grazing, and Capture for the international Pet Trade. Conservation actions have been implemented on < 20% of populations. Our results highlight the importance of a population-level approach in revealing the extent of threats to wild populations. It is critical to increase the scope of conservation actions to reduce the capture of wild parrots for pets., La lista completa de autores puede encontrarse en el archivo asociado., Facultad de Ciencias Naturales y Museo

The Slender-billed Parakeet (Enicognathus leptorhynchus) is a psittacine endemic to southern Chile and an obligate secondary cavity-nester. In the central valley of southern Chile, most (94%) of the known Slender-billed Parakeet nests have occurred in large, mature southern beech (Lophozonia obliqua) trees (locally known as “pellines”). As relicts of the original old-growth forests of southern Chile, most pellines have been lost due to extensive land-clearing throughout the region, potentially threatening long-term persistence of the Slender-billed Parakeet. We conducted our study in the central valley of southern Chile, near the city of Osorno during three consecutive nesting seasons (November–January, 2008–2011). Nest trees used by Slender-billed Parakeets were located by direct observation of parakeet activities and through interviews with local residents, some of whom were former parrot nest poachers. Nest cavities were accessed, inspected and measured using single-rope climbing techniques. We report means, standard errors, 95% confidence intervals and ranges for 11 cavity-related variables. We also report clutch sizes encountered in active nests, and age estimates of nest trees based on known growth rates of Lophozonia trees in southern Chile. Linear regressions were used to evaluate potential relationships between cavity-related variables and clutch size. We located and measured 38 Lophozonia tree cavities used for nesting by Slender-billed Parakeets. Compared to those used by other psittacines, nest trees were relatively large, averaging 30.4 ± 1.1 m in height with a mean diameter at breast height of 134.5 ± 4.7 cm. Based on estimated annual diameter increment, ages of nest trees ranged from approximately 209–485 years. Nest cavities entrances averaged 12.5 ± 0.9 m in height above ground level. Cavity entrance widths averaged 51.0 ± 13.3 cm (vertical) by 11.5 ± 0.7 cm (horizontal). Cavity entrance orientations were apparently random, with no directional preferences detected. Nest cavities were also relatively large, with a mean internal diameter of 39.6 ± 2.4 cm and mean depth of 90.3 ± 24.2 cm. Clutch sizes (2–9) were unusually large for psittacines of this size (ca. 280–300 g) and broods of up to seven well-developed nestlings were observed. We found that the deep and spacious cavities provided by pellines facilitate successful rearing of large broods, thereby maximizing productivity and fitness. The existence of pellines has apparently allowed Slender-billed Parakeets to adapt successfully to a wholesale loss of ancestral habitat to anthropogenic modifications. Immediate and strategic conservation measures, such as protection of existing pellines and the regeneration and recruitment of additional ones, are recommended for ensuring the survival of Slender-billed Parakeet populations throughout the central valley of southern Chile.

Reintroduction programs often face the challenge of sustaining multiple populations, each with unique demographic rates. Decision makers must determine how to allocate afinite number of captive-reared animals among these populations to achieve the fundamental objective of the program. We explored the optimal allocation of captive-reared Puerto Rican parrots (Amazona vittata) to 3 distinct populations: a struggling relict (population 1), a successfully reintroduced population (population 2), and a potential (new) population (population 3). We illustrate decision tradeoffs using 4 hypothetical scenarios of demographic performance created using the parrot literature and expert opinion and find the optimal decision by formulating the problem as a Markov decision process. Across all scenarios, our analysis favored releasing parrots into population 2 first when population sizes were small, followed by releases into population 3, and subsequently to population 1. The point in the decision space at which these transitions occurred was a function of location demographic rates. Releasing parrots in a location harboring an extant population versus a location that does not is advisable if differences in environmental conditions that promote population growth between locations are small. If management actions cannot ameliorate limiting factors in a location, decisions will favor translocations from such locations and allocations to locations where growth is more likely. When the cost of conducting a release is considered, managers should occasionally postpone releases to avoid these costs. This is optimal whenever the weighted contribution of the additional parrots to the sum of the discounted additional expected future population levels is less than the size of the fixed costs. This was most often the case for population 1 as costs increased. 2013 The Wildlife Society.

Species in the family Psittacidae may be particularly vulnerable to anthropogenic habitat transformations that reduce availability of suitable breeding sites at different spatial scales. In southern Chile, loss of native forest cover due to agricultural conversion may impact populations of Slender-billed Parakeets (Enicognathus leptorhynchus), endemic secondary cavity-nesting psittacids. Our objective was to assess nest-site selection by Slender-billed Parakeets in an agricultural-forest mosaic of southern Chile at two spatial scales: nest trees and the habitat surrounding those trees. During the 2008–2009 breeding seasons, we identified nest sites (N= 31) by observing parakeet behavior and using information provided by local residents. Most (29/31) nests were in mature Nothofagus obliqua trees. By comparing trees used for nesting with randomly selected, unused trees, we found that the probability of a tree being selected as a nest site was positively related to the number of cavity entrances, less dead crown, and more basal injuries (e.g., fire scars). At the nesting-habitat scale, nest site selection was positively associated with the extent of basal injuries and number of cavity entrances in trees within 50 m of nest trees. These variables are likely important because they allow nesting parakeets to minimize cavity search times in potential nesting areas, thereby reducing energetic demands and potential exposure to predators. Slender-billed Parakeets may thus use a hierarchical process to select nest sites; after a habitat patch is chosen, parakeets may then inspect individual trees in search of a suitable nest site. Effective strategies to ensure persistence of Slender-billed Parakeets in agricultural-forest mosaics should include preservation of both individual and groups of scattered mature trees.

We present the 13CO/C18O (J=3→2) Heterodyne Inner MilkyWay Plane Survey (CHIMPS) which has been carried out using the Heterodyne Array Receiver Program on the 15 m James Clerk Maxwell Telescope (JCMT) in Hawaii. The high-resolution spectral survey currently covers |b| ≤ 0°.5 and 28° ≲ l ≲ 46°, with an angular resolution of 15 arcsec in 0.5 km s-1 velocity channels. The spectra have amedian rms of~0.6 K at this resolution, and for optically thin gas at an excitation temperature of 10 K, this sensitivity corresponds to column densities of NH2 ~ 3 × 1020 cm-2 and NH2 ~ 4 × 1021 cm-2 for 13CO and C18O, respectively. The molecular gas that CHIMPS traces is at higher column densities and is also more optically thin than in other publicly available CO surveys due to its rarer isotopologues, and thus more representative of the three-dimensional structure of the clouds. The critical density of the J = 3 → 2 transition of CO is ≳104 cm-3 at temperatures of ≤20 K, and so the higher density gas associated with star formation is well traced. These data complement other existing Galactic plane surveys, especially the JCMT Galactic Plane Survey which has similar spatial resolution and column density sensitivity, and the Herschel infrared Galactic Plane Survey. In this paper, we discuss the observations, data reduction and characteristics of the survey, presenting integrated-emission maps for the region covered. Position-velocity diagrams allow comparison with Galactic structure models of the Milky Way, and while we find good agreement with a particular four-arm model, there are some significant deviations. © 2015 The Authors.

With 28% of the 350 species of parrots considered threatened, numerous conservation efforts have been initiated for these species. Among these, the restoration or establishment of new populations has increasingly relied on reintroductions as a conservation strategy, often with mixed or uncertain results. We reviewed the results and methodologies of 47 distinct releases and reintroductions of psittacines in nine different countries worldwide over the past 25 years to identify common denominators of successful efforts. To do so, we established a uniform and objective definition of reintroduction success (first-year survival >0.50 and released birds breeding with conspecifics, either captive-reared or wild), and applied generalized linear models and information-theoretic model selection to multiple datasets to identify important predictor variables. We identified several likely predictors of successful psittacine reintroductions, relating to predation mitigation, habitat quality, and post-release supplementation that may provide guidance for future efforts. We also advocate SWOT analysis for objectively evaluating the suitability of potential reintroduction sites.

Despite the importance of the post-fledging period in avian population dynamics, little is known about habitat use during this life stage. We examined habitat selection by radio-tracked juvenile Slender-billed Parakeets (Enicognathus leptorhynchus) at multiple spatial scales in a fragmented agricultural landscape of southern Chile. Using home ranges versus study area (home-range selection) and locations versus combined home range (habitat-type selection), we based spatial analyses of habitat selection on the population level. Slender-billed Parakeets made similar habitat choices across the hierarchical levels examined, except for riparian and native second-growth forests, which they avoided at the level of overall home-range selection but used in proportion to availability at the level of habitat-type selection. Farmland and pastures with high densities of scattered mature trees were the only habitats positively selected at multiple spatial scales, adding to the increasing amount of literature h...

Critically Endangered Puerto Rican parrots Amazona vittata are one of the rarest birds in the world. Several exotic mammal species capable of preying on Puerto Rican parrots cohabit the Caribbean National Forest with the only wild population of these parrots. We used tracking plates, monitoring blocks and trapping to index black rats, small Indian mongooses and feral cats in parrot habitat and in public-use areas in the same habitat type. We had high trap success for black rats at all sites (42% of all sites combined), among the highest reported in the world. Rat response to monitoring (nontoxic bait) blocks was universally high, regardless of ground or tree placement. Mongooses were present at all sites, with a greater proportion of plates tracked within the forest than at public-use sites. Cats were present at all forest sites and one of the public-use sites. Presence of the three species did not appear to be linked to human disturbance. Because only 30–40 Puerto Rican parrots survive in the wild, with as few as three pairs nesting in 2002, we concluded that the abundance and pervasiveness of exotic mammalian predators poses a greater threat to the parrots than has been generally acknowledged. This is evidenced by mammalian predation during recent parrot breeding seasons, including six fledglings taken by mongooses and one nest failure from rats during 2000–2003.

We report first-year survival for 34 captive-reared Puerto Rican Parrots (Amazona vittata) released in the Caribbean National Forest, Puerto Rico between 2000 and 2002. The purpose of the releases were to increase population size and the potential number of breeding individuals of the sole extant wild population, and to refine release protocols for eventual reintroduction of a second wild population elsewhere on the island. After extensive prerelease training, we released 10 parrots in 2000, 16 parrots in 2001, and eight parrots in 2002 ranging in age from 1–4 years old. All birds were equipped with radio-transmitters to monitor survival. The overall first-year survival estimate for the 34 parrots was 41% (CI = 22%–61%). Only one parrot died within the first week postrelease, with most (94%) surviving for at least eight weeks after release. Most (54%) documented mortalities were due to raptor predation, which claimed 21% of all released parrots. A captive-reared bird (male, age one), released in 2001, paired with a wild female and fledged two young in 2004. We also calculated survival based on 0% and 50% of observed predation losses and found hypothetical survival rates of 72% and 54%, respectively. Rigorous prerelease training and acclimation was believed to have improved initial postrelease parrot survival, and releasing mixed age-class groups suggests the potential for shortening the time to recruitment. Supervivencia de Individuos de Amazona vittata Criados en Cautiverio y Liberados en el Bosque Nacional del Caribe Resumen. Determinamos la supervivencia de 34 individuos de cotorras Amazona vittata criados en cautiverio y liberados en el Bosque Nacional del Caribe, Puerto Rico entre el 2000 y el 2002. El propósito de las liberaciones era aumentar el tamaño de la población y el número potencial de individuos reproductores en la única población silvestre remanente, y refinar los protocolos de liberación para eventualmente establecer una segunda población silvestre en la isla. Después de un adiestramiento extensivo, liberamos 10 cotorras en el 2000, 16 cotorras en el 2001, y ocho cotorras en el 2002 fluctuando en edades entre uno y cuatro años. Cada individuo se liberó con un radio transmisor para determinar su supervivencia. La tasa general de supervivencia para 34 cotorras después de un año fue de 41% (IC = 22–61%). Sólo una cotorra murió durante la primera semana post-liberación, con la mayoría (94%) sobreviviendo por lo menos ocho semanas después de liberadas. La mayoría (54%) de la mortandad se debió a la depredación por aves rapaces, la que reclamó 21% de todas las cotorras liberadas. Una cotorra criada en cautiverio (macho, un año de edad), y liberada en el 2001, se apareó con una hembra silvestre y produjeron dos volantones en el 2004. Reduciendo la mortandad por aves rapaces informada en este estudio en un 100%, o en un 50%, resultó en tasas hipotéticas de supervivencia del 72% y 54%, respectivamente. Creemos que el adiestramiento y la aclimatación rigurosa pre-liberación mejoraron la supervivencia inicial post-liberación, y que la liberación de grupos de cotorras de edades mixtas sugiere el potencial de acortar el tiempo de reclutamiento.

We report first-year survival rates of 49 captive-reared Hispaniolan Parrots (Amazona ventralis) released in Parque Nacional del Este, Dominican Republic. Our goal was to learn about factors affecting postrelease survival. Specifically, we tested if survival was related to movements and whether modifying prerelease protocols influenced survival rates. We also estimated survival in the aftermath of Hurricane Georges (22 September 1998). Twenty-four parrots, fitted with radio-transmitters, were released between 14 September and 12 December 1997. Twenty-five more were released between 29 June and 16 September 1998. First-year survival rates were 30% in 1997 and 29% in 1998. Survival probability was related to bird mobility. In contrast to birds released in 1997, none of the 25 parrots released in 1998 suffered early postrelease mortality (i.e., 3–5 days after release). Two adjustments to prerelease protocols (increased exercise and reduced blood sampling) made in 1998 may have contributed to differences in mobility and survival between years. The reduction of early postrelease mortality in 1998 was encouraging, as was the prospect for higher first-year survival (e.g., 30% to 65%). Only one death was attributed to the immediate impact of the hurricane. Loss of foraging resources was likely a major contributor to ensuing mortality. Birds increased their mobility, presumably in search of food. Survival rates dropped 23% in only eight weeks posthurricane. This study underscores the value of standardized prerelease protocols, and of estimating survival and testing for factors that might influence it. Inferences from such tests will provide the best basis to make adjustments to a release program. Supervivencia de Amazona ventralis Criadas en Cautivero y Liberadas en el Parque Nacional del Este, República Dominicana Resumen. Determinamos la supervivencia de 49 individuos de Amazona ventralis criados en cautiverio y liberados en el Parque Nacional del Este, República Dominicana. El proyecto se diseñó para aprender sobre los factores que pueden influenciar la supervivencia de las cotorras dominicanas. Específicamente, pusimos a prueba si la supervivencia estaba relacionada a movimientos y si modificaciones al protocolo de pre-liberación influenciaron la supervivencia. También estimamos la supervivencia de las cotorras después del paso del huracán Georges el 22 de septiembre 1998. En 1997 se liberaron 24 cotorras con radio transmisores entre el 14 de septiembre y el 12 de diciembre. Otras 25 se liberaron entre el 29 de junio y el 16 de septiembre de 1998. La estimación de la supervivencia en 1997 fue de un 30% y en 1998 de un 29%. La probabilidad de supervivencia estuvo relacionada a la movilidad del ave. En comparación con las cotorras liberadas en 1997, ninguna de las cotorras liberadas en 1998 murió durante los primeros 3–5 dias post-liberación. Dos ajustes a los protocolos de pre-liberación en 1998 contribuyeron probablamente a las diferencias en movilidad y supervivencia entre años. Este resultado fue alentador, así como el prospecto de alcanzar tasas más altas de supervivencia (e.g., 30% a 65%). La muerte de sólo una cotorra se atribuye al impacto directo del huracán. La pérdida de recursos alimenticios probablemente contribuyó fuertemente a la mortandad subsiguiente. Las cotorras exhibieron mayor movilidad, presumiblemente en búsqueda de frutos. La tasa de supervivencia disminuyó un 23% en solo ocho semanas después del huracán. Este estudio enfatiza el valor de protocolos de preliberación estandarizados y de estimaciones de tasas de supervivencia que ponen a prueba factores que la puedan influenciar. Las inferencias de dichas pruebas proveerán un mejor fundamento para ajustar los programas de liberación.

American black bear (Ursus americanus) populations were significantly reduced throughout their range, particularly in southeastern North America. Currently, populations in this region are very fragmented, resulting in concern over possible barrier effects of rivers to normal bear movements and dispersal. This is particularly true for Mississippi, where black bear dispersal into the state is critical if populations are to be recovered. Thus, we studied the relative effects of rivercourses on bear movements and dispersal patterns in southeastern Arkansas, 1992–1996. We captured, radiocollared, and uniquely tagged 40 bears and used radiotelemetry to determine their movements. The Mississippi River (width ≈1600 m) deflected bear movements, whereas the White River (width ≈200 m) was not a barrier to bear movements or dispersal patterns. Frequency of river crossing differed by gender (P=0.007) and season (P

Most habitats available to black bear (Ur,~usamericanus) in the Mississippi Alluvial Valley (M.4V) consist of seasonally flooded commercial forests where lack of suitable dens may limit population growth. \Ve studied interactions between forest management and flooding relative to female black bear denning. Denning behavior differed between commercial and noncommercial forests. Females used tree dens exch~sivelyon nonco~nmercialforests, whereas on commercial forests, most (83%) were ground dens. L7ariationsin ground den elevation resulted in differing inundation probabilities, altering survival prol.)abilities for neonates. On commercial forests, ground dens with similar inundation probabilities as tree dens allowed successful repro-duction to occur. Management practices that enhance suitable cover in areas of nlirlimal inundation probability may mitigate for lack of den trees in flood-prone landscapes. JOURNAL OF WILDLIFE MANAGEMENT 65(1):34-40 Key words: batture, black bear, denning, elevation, flooding, forest management, Misissippi Allu~ialValley, reproduction, topography, Ursus arnericanus.

We determined habitat use by adult eastern wild turkey females (Meleagris gallopavo silvestris) in the Mississippi River batture before and after selective thinning of riverfront hardwoods. Thinning reduced basal area from 20.3 to 13.7 m2/ha and decreased canopy closure from 60 to 49%. Midstory density was reduced from 1,421 to 971 stems/ha. One year after treatment mean understory cover increased from 31 to 57%. No nesting occurred because the study area was flooded both springs. Female turkey habitat use changed after thinning; the thinned area received the highest frequency of increased use. An increase in understory cover and hypothesized increase in productivity, particularly of wild turkey food items, apparently were the major attractions for the thinned area. J. WILDL. MANAGE. 52(2):253-260 Some of the largest populations of eastern wild turkeys occurred in the bottomland hardwoods along the Mississippi River (Dickson et al. 1978). This habitat was greatly reduced by extensive conversion to cropland. By 1977, only 20% of the original forest of the lower Mississippi delta remained (U.S. Fish and Wildl. Serv. 1978). Currently, wild turkeys of the Mississippi delta are most abundant in the batture (Hopkins et al. 1980), the land between the river and the flood control levee. Although relatively narrow, the batture along the lower third of the Mississippi River contains approximately 630,000 ha (Lower Mississippi Reg. Comprehensive Stud. Comm. 1974), most of which has not been converted to agricultural production because of seasonal flooding (Frey and Dill 1971). Timber management practices are the primary means for manipulating turkey habitat (Smith 1981). Little information is available on the effects of various forest harvesting methods on habitat use by wild turkeys (Hurst 1981) and immediate effects of a selective thinning (Smith 1986) on wild turkeys in the batture have not been studied. We investigated habitat use by wild turkey females before and after selective thinning of hardwoods in the Mississippi River batture of northeastern Louisiana. Funding for this study was provided by the National Wild Turkey Federation and the Louisiana Department of Wildlife and Fisheries through Louisiana State University. Research was conducted under the auspices of the Louisiana Cooperative Fish and Wildlife Research Unit; U.S. Fish and Wildlife Service, Louisiana State University, Louisiana Department of Wildlife and Fisheries, and Wildlife Management Institute, cooperating. Access to the study area was granted by International Paper Company and Anderson-Tully Company. This is Contribution 87-22-1310, Louisiana Agricultural Experiment Station.