Species Of Greatest Conservation Need Research Articles

Genetics, geography, and subspecies status of American mink in Florida, with an emphasis on Neogale vison evergladensis

Historical records of American mink (Neogale vison) in Florida suggest they occur in four populations, each currently recognized as a separate subspecies. The Everglades mink (N. v. evergladensis) is a state-listed threatened subspecies, and the Atlantic salt marsh mink (N. v. lutensis) and Gulf salt marsh mink (N. v. halilimnetes) are both Species of Greatest Conservation Need, but support for their taxonomic status is limited. We acquired 62 samples of mink for genetic analysis using mtDNA and microsatellite data with the objective of assessing the subspecies status of mink in Florida with an emphasis on evergladensis. We also compared historical and current range estimates of mink subspecies in Florida using museum specimens, public sightings, and detection records from scientific studies. All estimates of FST were significant when evergladensis was paired with other subspecies and both assignment tests and the Principal Coordinate Analysis separated evergladensis from other subspecies. The single mtDNA haplotype from evergladensis was not found elsewhere in Florida but was present in a subspecies outside of Florida (vulgivaga). Genetic diversity was lowest in evergladensis and highest for vulgivaga from Louisiana. We found support for lutensis as a separate taxonomic unit and assignment tests found some support for the genetic distinctiveness of halilimnetes. Sample sizes limited analyses in halilimnetes and prevented any conclusions about the subspecies status of mink in the Panhandle. Based on current range estimates, mink from evergladensis, lutensis, and halilimnetes are geographically isolated from one another and supports the genetic analysis. Using a more modern definition of subspecies that includes genetics, distribution, and ecology, we conclude that the data supports multiple subspecies of mink in Florida.

The relative contributions of habitat area, configuration, and vegetative diversity on snake and lizard presence in agricultural landscapes

AbstractNearly one in five reptile species is at risk of extinction. Changes in habitat area, its configuration, and vegetation diversity could affect habitat use, but their relative importance is understudied. We assessed how these factors affected reptile presence in agricultural landscapes figure in Iowa, United States, using 695 cover boards visited 16,441 times in 2015–2020. Species‐wise encounter rates ranged 0.0001–0.012. Eight of 11 species and 54.2% of individuals were species of greatest conservation need. Habitat area, configuration, and vegetation diversity influenced reptile presence similarly. Mean patch occupancy was 0.18 for common garter snake (CG, Thamnophis sirtalis) and 0.45 for all snakes (AS). Naïve presence was explained by effort (odds ratio [OR]AS = 1.83, ORCG = 1.79), vegetation diversity (ORAS = 1.28, ORCG = 1.28), woody cover (ORAS = 1.24, ORCG = 1.41), and patch size (ORAS = 1.30). Large patch prairies were more likely to contain snakes than other conservation practices (encounter = 0.291), and more likely to contain CG (0.098) than prairie contour strips (0.031), waterways (0.018), grass contour strips (0.016), or terraces (0.015). While we documented low overall reptile presence, their higher presence in large prairie patches underscores the importance of core nature reserves for reptile conservation.

Scenario planning and multispecies occupancy models reveal positive avian responses to restoration of afforested woodlands

Scenario planning is a powerful approach for assessing restoration outcomes under alternative futures. However, developing plausible scenarios remains daunting in complex systems like ecological communities. Here, we used Bayesian multispecies occupancy modeling to develop scenarios to assess woodland restoration outcomes in afforested communities in seven wildlife management areas in Arkansas, U.S.A. Our objectives were (1) to define plausible woodland restoration and afforestation scenarios by quantifying historic ranges of variation in mean tree cover and tree cover heterogeneity from 1986 to 2021 and (2) to predict changes in bird species richness and occupancy patterns for six species of greatest conservation need under two future scenarios: complete afforestation (100% tree cover) and woodland restoration (based on remotely sensed historic tree cover). Using 35 years of remotely sensed tree cover data and 6 years of bird monitoring data, we developed multispecies occupancy models to predict future bird species richness and occupancy under the complete afforestation and woodland restoration scenarios. Between 1986 and 2021, tree cover increased in all study areas—with one increasing 70%. Under the woodland restoration scenario, avian species richness increased up to 20%, and four of six species of greatest conservation need exhibited gains in occupancy probability. The complete afforestation scenario had negligible effects on richness and occupancy. Overall, we found decreasing tree cover to historic levels prior to widespread afforestation would provide community‐level benefits and would do little harm even to forest‐dependent species of conservation concern. Applying multispecies occupancy modeling within a scenario planning framework allows for comparing multiscale trade‐offs between plausible futures.

Leveraging a century of fisheries surveys to prioritize conservation efforts for species in Great Plains streams of Oklahoma (USA)

Abstract Although non‐game fishes typically dominate lists of threatened and imperilled species, funding mechanisms for non‐game species are usually less robust than those for game species. This imbalance emphasizes the need for methodologies to identify imperilled species effectively and ensure efficient allocation of limited conservation resources. A database comprising >3,900 fisheries surveys conducted between 1905 and 2020 in Great Plains streams of Oklahoma (USA) was used to develop methodology for identifying species in need of conservation by assessing differences in species occurrences and trends in species ranges through time. Changes in occurrence for 92 species at both river catchment and ecoregion scales were assessed. Generalized linear models indicated significant differences between historical and contemporary fish communities at both scales. Univariate testing showed 84 instances of species occurrences changing in at least one catchment. Declines in occurrence were observed for eight species currently listed as species of greatest conservation need in Oklahoma and were used to identify five candidate species for listing. Family‐level trends in species occurrences suggested declines of native true minnow species and increases in generalist sunfishes and catfishes through time. Trends in detections within each hydrologic unit code sampled were used as a proxy for tracking changes in species range within each catchment. Various species were used as case studies to highlight this method. The results demonstrate how managers can apply an empirical methodology that extracts information from long‐term datasets to optimize conservation efforts for stream fishes and associated taxa.

Status and Distribution of Freshwater Mussels in the Louisiana Section of Bayou Bartholomew

As a major tributary to the species-rich Ouachita River and one of the few remaining non-channelized rivers in the Alluvial Plains physiographic division, Bayou Bartholomew is a key ecosystem for the freshwater mussel diversity of southeast Arkansas and northeast Louisiana. Bayou Bartholomew is known to contain 16 mussel Species of Greatest Conservation Need (SGCN) but the mussel assemblage of the Louisiana section of Bayou Bartholomew has not been assessed since the early 2000s. In 2021, we sampled over 100 river km on the main channel of Bayou Bartholomew and four tributaries from just downstream of the Louisiana/Arkansas border to the confluence with the Ouachita River. We used a novel two-phase timed-search protocol to characterize the mussel assemblage and measured shell length (long axis) to determine the size distribution of each species encountered. A suite of relevant habitat variables and site attributes were also quantified or qualitatively noted. One site was selected for sampling using a grid survey to determine quantitative estimates of mussel density. Our survey confirmed the presence of 35 species including 12 SGCN in the Louisiana section of the Bayou Bartholomew drainage. In total, 3,292 live mussels representing 33 species were collected in the main channel, 234 live mussels representing 18 species were found in a quantitative grid, and four species were found in tributaries. Two additional species were only found in tributaries as dead shells. Length frequencies of all common and abundant species indicated ongoing annual recruitment. Patterns of ubiquity in the main channel of Bayou Bartholomew varied by species, and mussels were rare in the tributaries. Generalized linear modelling and non-metric multidimensional scaling analyses identified relationships between mussel assemblage composition and the distance from the confluence with the Ouachita River and habitat variables including substrates, depth, and mesohabitat types. A comparison with previous studies did not provide any evidence of major changes in overall mussel species distributions or occurrence in Bayou Bartholomew in Louisiana. We attribute the apparent stability in the mussel assemblage to the fact that major anthropogenic alterations such as channelization, impoundments, and watershed urbanization have been minimal since the earlier studies, and we conclude that Bayou Bartholomew will likely continue to be a hotspot of regional mussel diversity and a haven for several of Louisiana's SGCN if large-scale anthropogenic alterations to the system do not occur and management actions are taken to protect and allow for the persistence of heterogenous habitats.

Home Range and Habitat Use of Florida Box Turtles (Terrapene bauri) in the Ten Thousand Islands, Florida

For taxa with dispersal limitations, such as freshwater turtles, an understanding of their habitat and spatial needs can elucidate their risk to expected environmental and climatic changes. Florida Box Turtles (Terrapene bauri), a species of greatest conservation need, occurs in a diverse range of subtropical habitats on the Florida peninsula, including low-lying coastal areas subject to threats from climate change and sea level rise. We used radiotelemetry to assess the home range size and habitat use of Florida Box Turtles on a 37-ha anthropogenic, shell work island in southwestern Florida at the margin of its climatic niche. Home range calculated as 100% minimum convex polygons ranged from 0.29–1.52 ha with an average of 0.81 ha, which is consistent with, but smaller than, other parts of their range, and annual survivorship was estimated to be 0.875 (95% confidence interval = 0.67–1). Florida Box Turtles were most commonly located in tropical hardwood hammock forests (50.9%); other habitat use included shrub-scrub-cactus (29.6%), mangrove forest (13.4%) and shell barren (6.0%). Additional information on reproductive output, growth, temporal variation in survival, and response to disturbance such as hurricanes, storm overwash, and sea level rise is necessary to assess the long-term persistence of this population in the face of anticipated transitions of Florida's habitats because of global climate change.

The Southern Flying Squirrel (Glaucomys volans) in Lincoln, Nebraska

The southern flying squirrel (Glaucomys volans) is considered a species of greatest conservation need in Nebraska and listed as threatened in the state. Historically, the geographic range of the southern flying squirrel in Nebraska has been restricted to five eastern counties from a northern suburb of Omaha, Douglas Co., southward in the four counties of Sarpy, Otoe, Nemaha, and Richardson, all bordering the Missouri River on the east. In late November of 2018, a resident of Lincoln, Lancaster Co., Nebraska, contacted the Nebraska Game and Parks Commission about an animal found dead in his yard. This animal proved to be a southern flying squirrel, which was 50 to 70 miles [80 to112 km] west of the known geographic range of the species. Two additional individuals were subsequently observed at the original residence as were individuals in at least a total of 10 neighborhoods throughout the city of Lincoln. Clearly, a population of the southern flying squirrels is established and reproducing in Lincoln, but their origin is unknown. The source of this city-dwelling population may be from released/escaped pets, a natural dispersal from the Missouri River via the Platte River and Salt Creek, or inadvertent translocation when moving timber or fire wood.

Informing wind energy development: Land cover and topography predict occupancy for Arizona bats.

Wind energy is a growing source of renewable energy with a 3-fold increase in use globally over the last decade. However, wind turbines cause bat mortality, especially for migratory species. The southwest United States has high bat species diversity and is an important area for migratory species, although little is known about their seasonal distribution. To examine potential risk to bats in areas proposed for wind energy development, we characterized bat occupancy spatially and temporally across northern Arizona, identifying use during summer when bats are reproductively active and fall during the migratory season. Our objectives were to determine occupancy of migratory species and species of greatest conservation need and develop a probability of occupancy map for species to identify areas of potential conflict with wind energy development. We selected 92 sites in 10 clusters with potential for development and used acoustic detectors to sample bats in the summer and fall of 2016 and 2017 for 6 nights per site per year. We predicted response of migratory bat species and species of special concern to 9 landscape variables using Program MARK. During summer, higher densities of forest on the landscape resulted in a higher probability of occupancy of migratory species such as hoary bats (Lasiurus cinereus), silver-haired bats (Lasionycteris noctivagans), big free-tailed bats (Nyctinomops macrotis), and species of conservation need such as spotted bats (Euderma maculatum). During the fall, higher concentration of valleys on the landscape predicted occupancy of hoary bats, big free-tailed bats, and spotted bats. High bat occupancy in the fall was also associated with higher elevation and close proximity to forests. We recommend that wind turbines be placed in open, flat grasslands away from forested landscapes and concentrations of valleys or other topographic variation.

Carnivore Occupancy within the Early Successional Habitat of New England Cottontails

Abstract Predation pressure from carnivores can shape ecological communities and has significant consequences for prey species that are declining or recovering from historical declines. New England cottontails Sylvilagus transitionalis are a species of greatest conservation need in Connecticut and are experiencing continued decline associated with habitat loss. Restoration of early successional habitat is underway to address the most significant threat to their populations. However, one of the largest documented sources of mortality is associated with several key predators and remains a threat to recovery efforts. We sought to develop species-specific occupancy estimates of carnivores in early successional habitat and relate our findings to the potential recovery of New England cottontails. We conducted camera surveys at 34 sites in early successional habitat in or near New England cottontail focus areas throughout Connecticut and used the program MARK to estimate occupancy and detectability from detection data. We found key predators in early successional habitat, but their detectability was generally low. Occupancy was highest for coyotes Canis latrans, and regional occupancy differed only for bobcats Lynx rufus. Covariates that influenced parameter estimates in our models included high road densities and the intensity of New England cottontail and eastern cottontail Sylvilagus floridanus detections. Expanding carnivores, particularly coyote and bobcat, may place additional pressure on New England cottontail recovery in the state, but restoration efforts that promote contiguous habitat and reduce isolated patches where predation risk is higher will improve their chances of a long-term recovery.

Geospatial assessment of freshwater invasive species to inform turtle conservation and management

Abstract Identifying the ecological factors that determine the spread of invasive species is key to adequately managing endangered species in freshwater ecosystems. Invasive species are a main threat to turtles, which are targets of major conservation efforts worldwide. In freshwater ecosystems of the south‐western USA, invasive bullfrog (Lithobates catesbeianus) and crayfish species (Faxonius virilis and Procambarus clarkii) represent a major risk to the desert mud turtle (Kinosternon sonoriense sonoriense), state‐listed as a Species of Greatest Conservation Need in Arizona. As a species in the early stages of population decline, the desert mud turtle is a top candidate for the development of management plans to decrease extinction risk. An invasion risk assessment tool was built from available occurrence data for K. s. sonoriense and the invasive bullfrog and crayfish species in Arizona using 5,886 de‐duplicated records from public databases and reports from the Arizona Game and Fish Department. The occurrence density of K. s. sonoriense was calculated state‐wide to define populations in which the level of invasion by bullfrog and crayfish was assessed. The environmental factors associated with the abundance of invasive species in populations of K. s. sonoriense were then analysed. A higher prevalence of crayfish and bullfrog was detected in turtle populations located in perennial streams. Invasive abundance was significantly higher in turtle populations at higher elevation and closer to the main river trunk for both invasive taxa. Higher bullfrog abundance was detected near human settlements, whereas crayfish were more abundant further from human settlements. These results will inform which populations of K. s. sonoriense require intensive surveying and control of invasive species to maintain the health of native desert mud turtle populations. This study provides valuable information regarding the environmental conditions associated with the abundance of invasive species threatening turtle populations, helping to develop science‐based management of freshwater ecosystems.

Finding fishers: determining fisher occupancy in the Northern Rocky Mountains

AbstractMonitoring rare and elusive carnivores is inherently challenging because they often occur at low densities and require more resources to effectively assess status and trend. The fisher (Pekania pennanti) is an elusive mesocarnivore endemic to North America; in its western populations it is classified as a species of greatest conservation need. During winter of 2018–2019, we deployed remotely triggered cameras in randomly selected, spatially balanced 7.5‐km × 7.5‐km grid cells across a broad study area in western Montana, Idaho, and eastern Washington, USA. As part of this large‐scale, multi‐state monitoring effort, we conducted an occupancy assessment of the Northern Rocky Mountain fisher population at a range‐wide scale. We used non‐spatial occupancy models to determine the current extent of fisher occurrence in the Northern Rocky Mountains and to provide baseline occupancy estimates across a broad study area and a refined sampling frame for future monitoring. We used a spatial occupancy model to determine patterns in fisher occurrence across their Northern Rocky Mountain range while explicitly correcting for spatially induced overdispersion. Additionally, we assessed factors that influenced fisher occurrence through covariate occupancy modeling that considered predicted fisher habitat, site‐level environmental characteristics, and the influence of available harvest records (incidental and regulated). We detected fishers in 32 out of 318 (10%) of our surveyed cells, and estimated that overall, 160 (14%; 95% CI = 115–218) of 1,143 grid cells were occupied by fishers. Fisher occupancy was positively associated with our stratum that contained cells with a greater proportion of predicted fisher habitat and with proximity to nearest 2000–2015 harvest location. Fisher occupancy was weakly and positively associated with increased canopy cover. Our spatial model identified 2 areas with higher predicted occupancy: a large area across the Idaho Nez Perce‐Clearwater National Forest, and a smaller area in the Cabinet Mountain Range crossing the northern border of Idaho and Montana. We used spatial occupancy results from our original sampling frame to create a biologically derived refined sampling frame for future monitoring. Within the bounds of our refined sampling frame, we estimated that 155 (22%; 95% CI = 110–209) of 700 grid cells were occupied by fishers. By incorporating our increasing understanding of fisher habitat with contemporary analytical techniques, we defined current range‐wide occupancy of the Northern Rocky Mountain fisher population, identified core areas of fisher occurrence for future conservation efforts, and used our model results to create a refined sampling frame for future fisher monitoring in the Northern Rocky Mountains.

Molecular Identification of Sceloporus Lizards in the Laramie Mountains, Wyoming

Accurate information on species identities and distributions is critical for informing state land use and conservation policies. However, it can often be difficult to determine species identity using morphological data alone. Using phylogenetic methods, we determined the identity of Sceloporus lizards occupying the Laramie Mountains of Wyoming, between known ranges for Sceloporus tristichus and Sceloporus consobrinus. The ND1 mitochondrial gene was sequenced for 10 individuals from the Laramie Mountains and analyzed using maximum likelihood with 23 other samples of S. tristichus and S. consobrinus from throughout their ranges. The mtDNA gene tree places the Laramie Mountains populations within a clade of Sceloporus consobrinus that includes the Rocky Mountains in Colorado. Given the prevalence of mtDNA introgression in Sceloporus, we also conducted phylogenetic analyses using 4 nuclear loci (RAG-1, R35, BDNF, and PNN) for a subset of samples. Species tree analysis of the nuclear data further verified that the Laramie Mountains population belongs to S. consobrinus. Given the very limited data available on the range, prevalence, and ecology of S. consobrinus in Wyoming, as well its designation as a Species of Greatest Conservation Need in Wyoming, more research must be done to ensure protection of this population.

Freckled Madtom (Noturus nocturnus) Discovered in the Spring River Subbasin of Kansas

The distribution of Freckled Madtom (Noturus nocturnus) in Kansas includes the Lower Arkansas and Walnut River drainages of southcentral Kansas and the Little Osage, Marais des Cygnes, Neosho, and Verdigris River drainages of eastern Kansas. Freckled Madtom have not been previously reported from the Spring River subbasin in southeastern Kansas, although there is one record in 1942 from the Spring River subbasin of Missouri. Here we report the collection of five Freckled Madtom individuals from four locations along the Spring River mainstem in Cherokee County, Kansas during July–August 2020. All individuals were presumed to be young-of-year at ≤ 21 mm total length. Our finding of Freckled Madtom in the Spring River of Kansas has conservation implications since it is a Tier 2 Species of Greatest Conservation Need in the state.

Detection of Eastern Spotted Skunks on Pine Mountain in Southeastern Kentucky Using Baited Enclosed Track Plates

Spilogale putorius (Eastern Spotted Skunk) is listed as a species of greatest conservation need by Kentucky Department of Fish and Wildlife Resources. The objective of this study was to use enclosed track plates to investigate whether the species occurred in 7 protected areas along Pine Mountain in eastern Kentucky. We inventoried 30 sites from December 2017 through March 2018. We detected skunks in March at 2 different sites located at Kingdom Come Preserve and Hensley Pine Wildlife Management Area. We recommend further inventories for Eastern Spotted Skunks on Pine Mountain and comparisons of enclosed track plates to remote camera traps to detect Eastern Spotted Skunks in Appalachia.

Factors associated with distributions of six fishes of greatest conservation need in streams in midwestern USA

Abstract Many fish species of greatest conservation need (SGCN) in Iowa and Minnesota, USA, have been in decline for decades. A key reason for the decline is the alteration and degradation of naturally flowing streams owing to land use changes resulting from agricultural practices. Populations of several fishes have been adversely affected by widespread stream channelization that has resulted in more homogeneous stream habitats throughout Iowa and Minnesota. The goal of this study was to determine the abiotic and fish assemblage characteristics associated with the presence of these rare fishes. Electrofishing and seining were used to sample fish assemblages and 43 abiotic characteristics were measured at 111 sites in the North Raccoon and Boone River basins in central Iowa and the Rock River and Beaver Creek basins in north‐west Iowa and south‐west Minnesota during 2016 and 2017. Six SGCN, including the federally endangered Topeka shiner (Notropis topeka), were included in statistical modelling to determine habitat and fish assemblage characteristics associated with their presence. Species‐specific nonmetric multidimensional scaling ordinations indicated that abiotic characteristics and fish assemblages often differed between sites where SGCN were present and absent. Random forest and logistic regression models suggested that the presence of four of six SGCN were positively associated with species richness, whereas all other 10 important abiotic and fish assemblage variables were unique to only one or two of the six SGCN. Topeka shiners were present at 36% of sites and were positively associated with orangespotted sunfish (Lepomis humilis) catch per unit effort while being negatively associated with canopy cover and fantail darter (Etheostoma flabellare) catch per unit effort.

Activity, Movements, and Microenvironment Associations of Siren intermedia (Lesser Siren) in a Western Kentucky Wetland Complex

In Kentucky, at the periphery of the species' range, Siren intermedia (Lesser Siren) is a species of greatest conservation need. We monitored Lesser Sirens in a western Kentucky wetland complex from July 2018 to May 2019. Using funnel traps, we captured 60 Lesser Sirens and recaptured 2 individuals. Activity was greatest in July, and lowest October–January. Three Passive Integrated Transponder (PIT) telemetry surveys detected 7 PIT-tagged individuals; 1 Lesser Siren moved 36.9 m over 8 months. Capture success increased with warmer minimum water temperature. Body size upon first capture was unrelated to the microenvironment of the trap location. We recommend monitoring programs in western Kentucky concentrate funnel trapping in warm weather and use PIT telemetry to study movements.

Survivorship and Spatial Patterns of an Urban Population of Texas Horned Lizards

ABSTRACTHabitat fragmentation has negative consequences on threatened and endangered species by creating isolated populations. The Texas horned lizard (Phrynosoma cornutum) is experiencing population declines and localized extirpations throughout its range and has been classified as a species of greatest conservation need in Oklahoma, USA. Younger age classes have been poorly studied but may be vital to the stability of remaining populations. To address gaps in knowledge concerning subadult (hatchling and juvenile) morphometrics, survivorship, and home range sizes, we studied 2 cohorts of subadults, for 2 years each, covering their hatching and juvenile years (2016–2019). We used a combination of radio‐telemetry and novel harmonic radar methodology to study a closed population of Texas horned lizards in 15 ha of native grassland at Tinker Air Force Base, Oklahoma. Population abundance for adults and juveniles was estimated as 56.5 ± 5.5 lizards and density as 7.96 lizards/ha. Our lowest estimates of survival indicated an average survival probability for the hatchling life stage of 0.285 (95% CI = 0.15–0.44), which is lower than for adults on the site. Average home range size increased from hatchling to adult life stages. Our results will have an immediate effect on the planning and assessment of ongoing headstart and management programs for Texas horned lizards. © 2021 The Authors. The Journal of Wildlife Management published by Wiley Periodicals LLC on behalf of The Wildlife Society.

Long-term monitoring informs data-poor marine species in the northern Gulf of Mexico

Fisheries monitoring programs around the world are often designed to provide information on a wide range of species that come into contact with the program gear(s). Such programs may provide untapped abundance and distribution data for species of greatest conservation need (SGCN) and other rare or data-deficient species. We examined >30 years of fish sampling data from coastal Louisiana and found that 13 of 18 SGCN marine fishes were represented in existing routine monitoring data. Although some species were rarely reported, >100 records were available for seven species, with some species being reported several thousand times. Using these records, we were able to provide species-specific information about gear, season, location and timing for several marine fishes that were considered largely unknown. Given the paucity of information available for these species and the rapidly changing Louisiana coast, these biogeographic data may be important in the development of future conservation and management programs.

Poorly Vetted Conservation Ranks Can Be More Wrong Than Right: Lessons from Texas Land Snails

Setting priorities for scarce conservation dollars requires an accurate accounting of the most vulnerable species. For many invertebrates, lack of taxonomic expertise, low detectability, and funding limitations are impediments to this goal, with conservation ranks usually based on expert opinion, the published literature, and museum records. Because of biases and inaccuracies in these data, they may not provide an accurate basis for conservation ranks, especially when compared to de novo field surveys. We assessed this issue by comparative examination of these data sources in re-ranking the conservation status of all 254 land snail taxa reported from Texas, USA. We confirmed 198 land snail taxa, including 34 new state records. Our assessment of the entire land snail fauna of Texas resulted in (1) a near doubling of recommended Species of Greatest Conservation Need (SGCN) and (2) a 79% turnover in the makeup of SGCN taxa. Field sampling strongly outperformed museum and literature data in the encounter rate of both the entire fauna and all SGCN species, with the latter two demonstrating bias toward larger-bodied species. As a result, conservation priorities based solely on expert opinion and museum and literature records may be more wrong than right, with taxon-appropriate, targeted sampling required to generate accurate rankings.

Organochlorine Pesticides and Polychlorinated Biphenyls in American Oystercatchers Nesting along the Texas Gulf Coast

The American Oystercatcher (Haematopus palliatus palliatus) is an important breeding species along the Texas Gulf Coast, particularly between Galveston Bay and Corpus Christi, Texas, USA. American Oystercatchers are considered a species of greatest conservation need and are on the priority list for conservation by the National Fish and Wildlife Foundation. American Oystercatchers feed mainly on oysters (Ostreidae) and other bivalves, which are known to accumulate significant amounts of pollutants. We determined accumulation and potential effects of environmental contaminants, particularly organochlorine (OC) pesticides and polychlorinated biphenyls (PCBs) in blood of American Oystercatchers nesting along the Texas Gulf Coast, USA during 2012 and 2013. Plasma concentrations of OCs and PCBs were low. The most commonly detected OC pesticides were HCB, HCH, α chlordane, endosulfan, methoxychlor, p,p'-DDD, and p,p'-DDE. Total p,p'-DDE concentrations ranged from 2-10 ng/mL ww and total PCB concentrations ranged from 2-54 ng/mL ww. Mean p,p'-DDE concentrations were similar among regions; however, total PCBs were significantly greater (P = 0.0056) in blood from adult birds from West Galveston Bay, Texas, USA in 2013 than in blood from young collected in 2012, mostly also from West Galveston Bay. Overall, concentrations of OC pesticides in plasma were low; however, some PCB concentrations were above the NOAEC levels that have been associated with normal reproduction in other bird species.