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This dataset contains initial data from head-started alligator snapping turtles released by Louisiana Department of Wildlife and Fisheries (LDWF) from November 2015 to October 2016. In addition, it contains data from a five-day trapping effort at each of seven release sites by the United States Geological Survey (USGS) from late June to early October 2018. Trapping was completed using hoop nets of three sizes. We recaptured eight head-started alligator snapping turtles as well as four individuals native to the creek.

This note quantifies the number of embryos from a series of egg masses of the Southern Leopard Frog observed in the Atchafalaya Basin of south-central Louisiana.

A research priority can be defined as a knowledge gap that, if resolved, identifies the optimal course of conservation action. We (a group of geographically distributed and multidisciplinary research scientists) used tools from nominal group theory and decision analysis to collaboratively identify and prioritize information needs within the context of disease-associated amphibian decline, in order to develop a strategy that would support US management agency needs. We developed iterated influence diagrams to create and assess a unified research strategy. We illustrated a transparent process for identifying specific knowledge gaps in amphibian disease ecology relevant to environmental management, and then constructed a research plan to address these uncertainties. The resulting priorities include a need to: (1) understand the drivers of the community-disease relationship, (2) determine the mechanisms by which exposure to contaminants influence disease outcomes, (3) identify elements of terrestrial and aquatic habitats that stabilize host-pathogen dynamics, (4) discuss how metapopulations may be managed to reduce the speed and intensity of disease outbreaks, and (5) define the relationship between habitat management and the environmental and host microbiomes. Along with identifying research priorities for disease management, we present the details of the process used to develop a consensus plan for addressing disease-related declines in amphibians on federally managed lands of the United States.

Until publication, communication of provisional scientific findings beyond participants in the study is typically limited. This practice helps assure scientific integrity. However, a dilemma arises when a provisional finding has urgent societal consequences that may be exacerbated by delay. This dilemma may be particularly pronounced when a discovery concerns wildlife health, which could have implications for conservation, public health, or domestic animal health. Eleven researchers suggest that common concerns about directed prepublication communication largely stem from misperceptions and that none should cause a delay in the communication of time-sensitive provisional findings to appropriate authorities. Instead, they suggest that rapid communication of a provisional discovery could be beneficial, such as in the example they use involving the potential discovery of the amphibian fungal pathogen Bsal that is currently causing salamander die-offs in Europe.

We quantified the response of amphibian communities to climatic variability across the United States and Canada using more than 500,000 observations for 81 species across 86 study areas. We estimated the relationships between annual variation in climate variables and local colonization and persistence probabilities across more than 5000 surveyed sites. This allowed us to estimate sensitivity to change in five climate variables. Climate sensitivity differs greatly among eco-regions and depends on local climate, species life-history, and phylogeny. Local species richness was especially sensitive to changes in water availability during breeding and changes in winter temperature. These results allowed us to ask whether changing climate explains strong overall rates of decline in species richness observed in our data set. We found that recent change in the climate variables we measured does not explain why North American amphibian richness is rapidly declining, but does explain why some populations decline faster than others. 

The Cuban treefrog, Osteopilus septentrionalis, is native to Cuba, the Bahamas, and the Cayman Islands, and is invasive in areas where it has been introduced and established in the Caribbean as well as Hawaii and Florida. Despite repeated occurrences in several states over many years, it was not believed that Cuban treefrogs had successfully established outside of Florida in the mainland United States. From mid-September to mid-November 2017, we captured and removed 367 Cuban treefrogs in just four surveys in New Orleans, Louisiana. The impacts of this population on native treefrogs in this area is unknown but possibly severe as indicated by the paucity of observations of native treefrogs during our surveys. Eradication of this seemingly established population is improbable, but continued surveys will facilitate learning about the ecology and genetics of this novel population.

This paper summarizes the results of Bd and Bsal testing of 76 Gulf Coast Waterdogs captured from southeast Louisiana.

In 2016 ARMI and National Wildlife Health Center scientists conducted a nationwide sampling effort to detect the salamander chytrid fungus Batrachochytrium salamandrivorans (Bsal). Bsal is native to Asia where indigenous salamanders carry the fungus without disease symptoms. However, Bsal has been spread through human facilitation to Europe where it has been implicated in major population die-offs of wild salamanders. To date, no occurrence of Bsal has been documented in wild salamander populations in North America, but there is reason to think that it could arrive or already be here.

Between 2010 and 2014, 99% of the 750,000 salamanders imported into the U.S. were of Asian origin. Due to these obvious threats the U.S. Fish and Wildlife Service has halted importation of many salamanders, including the Asian species popular in the pet trade. However, we need to know if Bsal is already present. The introduction of Bsal into North American wild salamander populations could be particularly problematic given that North America is a global hotspot of salamander diversity being home to nearly half of all salamander species worldwide.

A current map of U.S. sites that have been surveyed to detect Bsal by the ARMI program is available on the ARMI website ( https://armi.usgs.gov/Bsal-studies/ ).

Large gaps exist in our knowledge of the ecology of stream-breeding plethodontid salamanders in the Gulf Coastal Plain. Data describing where these salamanders are likely to occur along environmental gradients, as well as their likelihood of detection, are important for the prevention and management of amphibian declines. We used presence/absence data from leaf litter bag surveys and a hierarchical Bayesian multispecies single-season occupancy model to estimate the occurrence of five species of plethodontids across reaches in headwater streams in the Gulf Coastal Plain. Average detection probabilities were high (range = 0.432-0.942) and unaffected by sampling covariates specific to the use of litter bags (i. e., bag submergence, sampling season, in-stream cover). Estimates of occurrence probabilities differed substantially between species (range = 0.092-0.703) and were influenced by the size of the upstream drainage area and by the maximum proportion of the reach that dried. The effects of these two factors were not equivalent across species. Our results demonstrate that hierarchical multispecies models successfully estimate occurrence parameters for both rare and common streambreeding plethodontids. The resulting models clarify how species are distributed within stream networks, and they provide baseline values that will be useful in evaluating the conservation statuses of plethodontid species within lotic systems in the Gulf Coastal Plain.

Since amphibian declines were first proposed as a global phenomenon over a quarter century ago, the conservation community has made little progress in halting or reversing these trends. The early search for a "smoking gun" was replaced with the expectation that declines are caused by multiple drivers. While field observations and experiments have identified factors leading to increased local extinction risk, evidence for effects of these drivers is lacking at large spatial scales. Here, we use observations of 389 time-series of 83 species and complexes from 61 study areas across North America to test the effects of 4 of the major hypothesized drivers of declines. While we find that local amphibian populations are being lost from metapopulations at an average rate of 3.79% per year, these declines are not related to any particular threat at the continental scale; likewise the effect of each stressor is variable at regional scales. This result - that exposure to threats varies spatially, and populations vary in their response - provides little generality in the development of conservation strategies. Greater emphasis on local solutions to this globally shared phenomenon is needed.

ARMI is uniquely qualified to provide information that is scalable from local to national levels and is useful to resource managers. Here we provide highlights and significant milestones of this innovative program. ARMI has now produced over 500 publications. We feature several in this fact sheet, but please visit our website (http://armi.usgs. gov) for additional information on ARMI products, to find summaries of research topics, or to search for ARMI activities in your area.

With ongoing climate change, many species are expected to shift their spatial and temporal distributions. To document changes in species distribution and phenology, detection/non-detection data have proven very useful. Occupancy models provide a robust way to analyze such data, but inference is usually focused on species spatial distribution, not phenology.
We present a multi-season extension of the staggered-entry occupancy model of Kendall et al. (2013), which permits inference about the within-season patterns of species arrival and departure at sampling sites. The new model presented here allows investigation of species phenology and spatial distribution across years, as well as site extinction/colonization dynamics.
We illustrate the model with two datasets on European migratory passerines and one dataset on North American tree frogs. We show how to derive several additional phenological parameters, such as annual mean arrival and departure dates, from estimated arrival and departure probabilities.
Given the extent of detection/non-detection data that are available, we believe that this modeling approach will prove very useful to further understand and predict species responses to climate change.

Reproductive aspects of Ambystoma salamanders were investigated at a site in Louisiana (2010–2012) and a site in Mississippi (2013). Three species occurred at the Louisiana site, Spotted Salamander (A. maculatum), Marbled Salamander (A. opacum), and Mole Salamander (A. talpoideum), whereas only Spotted Salamanders were studied at the Mississippi site. A total of 162 and 71 egg masses of Spotted Salamanders were examined at the Louisiana and Mississippi sites, respectively. Significantly more Spotted Salamander eggs per mass were observed at the Mississippi site (78.2) than the Louisiana site (53.8; p<0.001). The mean snout-vent length of female Spotted Salamanders at the Mississippi site (82.9 mm) was significantly larger than the Louisiana site (76.1 mm; p<0.001). Opaque Spotted Salamander egg masses were not found at the Mississippi site, but accounted for 11% of examined egg masses at the Louisiana site. The mean number of eggs per mass at the Louisiana site did not differ between opaque (47.3) and clear (54.6) egg masses (p=0.21). A total of 47 egg masses of the Mole Salamander were examined, with a mean number of 6.7 embryos per mass. Twenty-three individual nests of the Marbled Salamander were found either under or in decaying logs in the dry pond basins. There was no difference between the mean numbers of eggs per mass of attended nests (93.0) versus those that were discovered unattended (86.6; p=0.67). Females tended to place their nests at intermediate heights within the pond basin.

Artificial pipe-like refugia have been used by researchers for more than 40 years in anuran studies, and captured 28 species, primarily (82%) hylid treefrogs. Early pipe-like refugia were made using cut pieces of bamboo in the tropical forests of Puerto Rico, but more recent studies have used synthetic pipes and have occurred primarily in the southeastern United States. Although some studies have addressed particular aspects of pipe design, the diverse characteristics of the refugia as well as their placement in the environment have varied greatly, making comparisons among studies difficult. Here, we summarize and evaluate information regarding pipe designs and placement, address potential concerns for researchers, and suggest studies necessary to better interpret the data gained from this technique in anuran studies.

A fundamental goal of wetland restoration is to reinstate pre-disturbance hydrological conditions to degraded landscapes, facilitating recolonization by native species and the production of resilient, functional ecosystems. To evaluate restoration success, baseline conditions need to be determined and a reference target needs to be established that will serve as an ecological blueprint in the restoration process. During the summer wet seasons of 2010 and 2011, we used automated recording units to monitor a community of calling anuran amphibians in the Picayune Strand State Forest of southwest Florida, USA. This area is undergoing hydrological restoration as part of the Comprehensive Everglades Restoration Plan (CERP). We compared occurrence of anurans at sites in the restoration area, to nearby sites in relatively undisturbed habitat. We assessed the utility of the latter as restoration targets, using a hierarchical model of community species occupancy to estimate the probability of occurrence of anurans in restoration and reference locations. We detected 14 species, 13 of which were significantly more likely to occur in reference areas. All 14 species were estimated by our model to occur at these sites but, across both years, only 8–13 species were estimated to occur at restoration sites. The composition and structure of these habitats within and adjacent to the Picayune Strand State Forest indicate that they are suitable targets for habitat restoration, as measured by amphibian occurrence and species richness. These areas are important sources for recolonization of anuran amphibians as the hydrologically degraded Picayune Strand undergoes restoration to mitigate the effects of overdrainage and habitat loss.