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As part of an overall decline in biodiversity, populations of many organisms are declining and species are being lost at unprecedented rates around the world. This includes many populations and species of amphibians. Although numerous factors are affecting amphibian populations, we show potential direct and indirect effects of climate change on amphibians at the individual, population and community level. Shifts in amphibian ranges are predicted. Changes in climate may affect survival, growth, reproduction and dispersal capabilities. Moreover, climate change can alter amphibian habitats including vegetation, soil, and hydrology. Climate change can influence food availability, predator-prey relationships and competitive interactions which can alter community structure. Climate change can also alter pathogen-host dynamics and greatly influence how diseases are manifested. Changes in climate can interact with other stressors such as UV-B radiation and contaminants. The interactions among all these factors are complex and are probably driving some amphibian population declines and extinctions.

I examined the potential influence of climate change on the dynamics of a previously studied hybrid zone between a pair of terrestrial salamanders at the Coweeta Hydrologic Laboratory, U.S. Forest Service, in the Nantahala Mountains of North Carolina, USA. A 16-year study led by Nelson G. Hairston, Sr. revealed that Plethodon teyahalee and Plethodon shermani hybridized at intermediate elevations, forming a cline between ‘pure’ parental P. teyahalee at lower elevations and ‘pure’ parental P. shermani at higher elevations. From 1974 to 1990 the proportion of salamanders at the higher elevation scored as ‘pure’P. shermani declined significantly, indicating that the hybrid zone was spreading upward. To date there have been no rigorous tests of hypotheses for the movement of this hybrid zone. Using temperature and precipitation data from Coweeta, I re-analyzed Hairston's data to examine whether the observed elevational shift was correlated with variation in either air temperature or precipitation from the same time period. For temperature, my analysis tracked the results of the original study: the proportion of ‘pure’P. shermani at the higher elevation declined significantly with increasing mean annual temperature, whereas the proportion of ‘pure’P. teyahalee at lower elevations did not. There was no discernable relationship between proportions of ‘pure’ individuals of either species with variation in precipitation. From 1974 to 1990, low-elevation air temperatures at the Coweeta Laboratory ranged from annual means of 11.8 to 14.2 °C, compared with a 55-year average (1936–1990) of 12.6 °C. My re-analyses indicate that the upward spread of the hybrid zone is correlated with increasing air temperatures, but not precipitation, and provide an empirical test of a hypothesis for one factor that may have influenced this movement. My results aid in understanding the potential impact that climate change may have on the ecology and evolution of terrestrial salamanders in montane regions.

The act of cannibalism, the killing and consumption of all or part of an individual of the same species, occurs widely in nature, including bacteria, protozoans, invertebrates, and vertebrates, as well as humans. It plays a role in economically important pest populations and aspects of biocontrol. It is a serious problem for domestic animal and fisheries industries and in colonies of mice and rats used for medical research due to the crowded conditions under which these animals are often kept. Perhaps best known is the case of sexual cannibalism when the female kills and then eats its male mate during courtship and mating, as in some species of praying mantids. Cannibalism can greatly influence populations regulated by density-dependent factors. Cannibalistic populations may persist when food is severely limited, whereas a noncannibalistic but otherwise identical population would go extinct. Dramatic shifts in the structure of entire biological communities may result from the dynamics within the cannibal population. Acts of cannibalism can incur significant costs, most notably risk of retaliation by the intended victim and risk of acquiring parasites and diseases from infected conspecifics. The cost of evolutionary fitness will depend upon the degree of genetic relatedness between cannibal and victim. Cannibals may be morphologically distinct from noncannibals of the same species, as occurs in some lower eukaryotes and larval amphibians.

A methods paper describing the influence of bait on capture efficiency of two genera of large aquatic salamanders.

From 1999 to 2006, we sampled > 1200 amphibians for the fungal pathogen Batrachochytrium dendrobatidis (Bd) at 30 sites in the southeastern USA. Using histological techniques or PCR assays, we detected chytrid infection in 10 species of aquatic-breeding amphibians in 6 states. The prevalence of chytrid infection was 17.8% for samples of postmetamorphic amphibians examined using skin swab-PCR assays (n = 202 samples from 12 species at 4 sites). In this subset of samples, anurans had a much higher prevalence of infection than caudates (39.2% vs. 5.5%, respectively). Mean prevalence in ranid frogs was 40.7%. The only infected salamanders were Notophthalmus viridescens at 3 sites. We found infected amphibians from late winter through late spring and in 1 autumn sample. Although we encountered moribund or dead amphibians at 9 sites, most mortality events were not attributed to Bd. Chytridiomycosis was established as the probable cause of illness or death in fewer than 10 individuals. Our observations suggest a pattern of widespread and subclinical infections. However, because most of the sites in our study were visited only once, we cannot dismiss the possibility that chytridiomycosis is adversely affecting some populations. Furthermore, although there is no evidence of chytrid-associated declines in our region, the presence of this pathogen is cause for concern given global climate change and other stressors. Although presence-absence surveys may still be needed for some taxa, such as bufonids, we recommend that future researchers focus on potential population-level effects at sites where Bd is now known to occur.

Southern Leopard Frogs, Rana sphenocephala, are habitat generalists occurring in virtually all freshwater habitats within their geographic range, whereas Gopher Frogs, Rana capito, typically breed in ponds that do not normally contain fish. To evaluate the potential for predation by fish to influence the distribution of these species, we conducted a randomized factorial experiment. We examined the survival rate and behavior of tadpoles when exposed to Warmouth Sunfish, Lepomis gulosus, Banded Sunfish, Enneacanthus obesus, and Eastern Mosquitofish, Gambusia holbrooki. We also conducted a choice experiment to examine the survival rate of the two species of tadpoles when a predator is given a choice of both species simultaneously. Lepomis gulosus consumed the most tadpoles and ate significantly more tadpoles of R. capito than R. sphenocephala. Gambusia holbrooki injured the most tadpoles, especially R. capito. Enneacanthus obesus did not have an effect on behavior or survival of either anuran species. Tadpoles of both anurans increased hiding when in the presence of L. gulosus and G. holbrooki, but a greater proportion of R. capito hid than did R. sphenocephala. Our results suggest that R. capito are more vulnerable to predation by fish than are R. sphenocephala. The introduction of fish may play a role in population declines of certain anurans breeding in normally fish-free wetlands, and even small fish, such as mosquitofish, may have significant negative effects on the tadpoles of R. capito.

To design effective and efficient research and monitoring programs researchers must have a thorough understanding of the capabilities and limitations of their sampling methods. Few direct comparative studies exist for aquatic sampling methods for amphibians. The objective of this study was to simultaneously employ seven aquatic sampling methods in 10 wetlands to compare amphibian species richness and number of individuals detected with each method. Four sampling methods allowed counts of individuals (metal dipnet, D-frame dipnet, box trap, crayfish trap), whereas the other three methods allowed detection of species (visual encounter, aural, and froglogger). Amphibian species richness was greatest with froglogger, box trap, and aural samples. For anuran species, the sampling methods by which each life stage was detected was related to relative length of larval and breeding periods and tadpole size. Detection probability of amphibians varied across sampling methods. Box trap sampling resulted in the most precise amphibian count, but the precision of all four count-based methods was low (coefficient of variation > 145 for all methods). The efficacy of the four count sampling methods at sampling fish and aquatic invertebrates was also analyzed because these predatory taxa are known to be important predictors of amphibian habitat distribution. Species richness and counts were similar for fish with the four methods, whereas invertebrate species richness and counts were greatest in box traps. An effective wetland amphibian monitoring program in the southeastern United States should include multiple sampling methods to obtain the most accurate assessment of species community composition at each site. The combined use of frogloggers, crayfish traps, and dipnets may be the most efficient and effective amphibian monitoring protocol.

The tailed frog Ascaphus truei Stejneger, 1899 is the most primitive extant anuran and the sister taxon to the clade of all other living frogs. The species occupies two disjunct ranges in the Northwest region of North America: the Cascade Mountains and coastal area from British Columbia to Northern California, and an inland range in the northern Rocky Mountains and the Blue and Wallowa mountains. A previous study led to the isolation of eight peptides with antimicrobial activity termed the ascaphins)from skin secretions of A. truei from the coastal range. The present study has used peptidomic analysis to identify the products of orthologous ascaphin genes in electrically-stimulated skin secretions from inland range specimens. Structural characterization of the peptides demonstrated that ascaphins from the inland range contained the following amino acid substitutions compared with orthologs from the coastal range frogs: ascaphin-1 ((Ala^12->Glu), ascaphin-3 (Asp^4->Glu), ascaphin-4 (Ala^19->Ser), ascaphin-5 (Lys^12->Thr), and ascaphin-7 (Gly^8->Ser and Ser^20->Asn). Orthologs of ascaphins-2, -6, and -8 were not identified but a paralog of ascaphin-5, identical to ascaphin-5 from coastal range frogs, was found. The data support the claims, derived from analysis of the nucleotide sequences of mitochondrial genes, that the inland populations of the tailed frog should be recognized as a distinct species, the Rocky Mountain tailed frog Ascaphus montanus and that the divergence of the species from A. truei probably occurred in the late Miocene (approximately 10 Mya).

Excepts from the introduction to the published papers arising from the 6th World Congress of Herpetology in Manuas.

Introduction (excerpt)to disease symposium publication following the 6th World Congress of Herpetology in Manaus: The goal of the symposium, Amphibian disease: Where do we go from here?, was to foster discussion of “what comes next?” in the efforts of the global scientific community to combat amphibian decline, specifically in the arena of disease. The symposium included presentations from Australia, Denmark, Ecuador, Spain, Kenya and the United States. Topics ranged from laboratory studies to landscape-scale field studies. Although the debate on “what comes next” remains in progress, the symposium prompted discussion and increased international collaborations – including subsequent workshops in Australia and Switzerland. The series of papers from this symposium, featured in this issue, do not provide a roadmap of what comes next, but illustrate the diverse nature of research into amphibian diseases and highlight some of the promising directions being pursued to understand the effects of disease on amphibian populations

1. Estimates of demographic parameters for females, in many organisms, are sparse. This is particularly worrisome as more and more species are faced with high extinction probabilities and conservation increasingly depends on actions dictated by complex predictive models that require accurate estimates of demographic parameters for each sex and species.

2. This study assesses demographic parameters, specifically temporary emigration and survival, for females, a class that has been difficult to investigate historically because of lack of data. Amphibians provide a particularly good example because there is global concern about amphibian decline yet most demographic parameter estimates are based on data from males, which we show can lead to erroneous conclusions.

3. We use 10 years of capture-recapture data from boreal toads (Bufo boreas) and the multi-state open robust design model to provide evidence for the occurrence of skipped breeding opportunities (i.e., temporary emigration) in females. This is the first time that the open robust design model has been applied to an analysis of an amphibian population that we are aware of.

4. We determined that the transition from breeder to non-breeder is obligate and the probability of a non-breeder remaining a non-breeder is 64%, thus temporary emigration is first-order Markovian in nature, where breeding probability is dependent on the previous year’s activity, i.e. if a female did not breed in year one, there is a 36% chance that she will breed in year two. With temporary emigration accounted for, we estimated between-year female survival at 87%.

5. Establishing the occurrence of temporary emigration not only reduces bias in estimates of survival probabilities, but also provides information about expected breeding attempts by females, a critical element in understanding the ecology of an organism and the impacts of outside stressors and conservation actions.

Understanding the distribution of chytridiomycosis, both at global and local scales, is important to controlling its impacts on host species (e.g., biocontrol or eradication) and to managing host amphibian populations (e.g., reintroduction and habitat management). In response to this, efforts to map observations of Batrachochytrium dendrobatidis (Bd) are underway to better understand its distribution and impact on amphibian populations. (e.g www.spatialepidemiology.net\Bd).
While there are many legitimate reasons to sample opportunistically for this pathogen, we question the validity of continuing this sort of exercise without a more cohesive and directed effort to apply the information to management of Bd. We use a recent example (Scalera et al. 2008) and some additional data from Denmark to discuss this question.

Effective monitoring programs are designed to track changes in the distribution, occurrence, and abundance of species. We developed an extension of Royle and Kéry’s (2007) single species model to estimate simultaneously temporal changes in probabilities of detection, occupancy, colonization, extinction, and species turnover using data on calling anuran amphibians, collected from 2002 to 2006 in the Lower Mississippi Alluvial Valley of Louisiana, USA. During our 5-yr study, estimates of occurrence probabilities declined for all 12 species detected. These declines occurred primarily in conjunction with variation in estimates of local extinction probabilities (cajun chorus frog [Pseudacris fouquettei], spring peeper [P. crucifer], northern cricket frog [Acris crepitans], Cope’s gray treefrog [Hyla chrysoscelis], green treefrog [H. cinerea], squirrel treefrog [H. squirella], southern leopard frog [Lithobates sphenocephalus], bronze frog [L. clamitans], American bullfrog [L. catesbeianus], and Fowler’s toad [Anaxyrus fowleri]). For 2 species (eastern narrow-mouthed toad [Gastrophryne carolinensis] and Gulf Coast toad [Incilius nebulifer]), declines in occupancy appeared to be a consequence of both increased local extinction and decreased colonization events. The eastern narrow-mouthed toad experienced a 2.5-fold increase in estimates of occupancy in 2004, possibly because of the high amount of rainfall received during that year, along with a decrease in extinction and increase in colonization of new sites between 2003 and 2004. Our model can be incorporated into monitoring programs to estimate simultaneously the occupancy dynamics for multiple species that show similar responses to ecological conditions. It will likely be an important asset for those monitoring programs that employ the same methods to sample assemblages of ecologically similar species, including those that are rare. By combining information from multiple species to decrease the variance on estimates of individual species, our results are advantageous compared to single-species models. This feature enables managers and researchers to use an entire community, rather than just one species, as an ecological indicator in monitoring programs.

Butachlor is the most commonly used herbicide on paddy fields in Taiwan and throughout Southeast Asia. Since paddy fields provide habitat for pond breeding amphibians, we examined growth, development, time to metamorphosis, and survival of alpine cricket frog tadpoles (Fejervarya limnocharis) exposed to environmentally realistic concentrations of butachlor. We documented negative impacts of butachlor on survival, development, and time to metamorphosis, but not on tadpole growth. The 96-h LC50 for tadpoles was https://0.87 mg/L, much lower than the 4.8 mg/L recommended dosage for application to paddy fields. Even given the rapid breakdown of butachlor, tadpoles would be exposed to concentrations in excess of their 96 h LC50 for an estimated 126 h. We also documented DNA damage (genotoxicity) in tadpoles exposed to butachlor at concentrations an order of magnitude less than the 4.8 mg/L recommended application rate. We did not find that butachlor depressed cholinesterase activity of tadpoles, unlike most organophosphorus insecticides. We conclude that butachlor is likely to have widespread negative impacts on amphibians occupying paddy fields with traditional herbicide application.

The US Geological Survey’s Amphibian Research and Monitoring Initiative (ARMI) is a national project with goals to monitor the status and trends of amphibians, conduct research on causes of declines, and provide information and support to management agencies for conservation of amphibian populations. ARMI activities are organized around extensive inventories and place-based monitoring (such as collaboration with the Greater Yellowstone I&M Network), and intensive population studies and research at selected locations (apex sites). One such is an oxbow pond on the Buffalo Fork near the Black Rock Ranger Station east of Grand Teton National Park. We have been conducting capture-mark-recapture of boreal toads (Anaxyrus boreas) at Black Rock since 2002. In concert with studies of other toad populations in the Rocky Mountains, we have documented a high rate of incidence of the chytrid fungus Batrachochytrium dendrobatidis (Bd) and a negative rate of growth of the toad population, but not the population crash or extinction observed in other populations with high occurrence of Bd.
Long-term observations at other ARMI apex sites have proven invaluable for studying effects of climate change on amphibian behavior, and the Black Rock site has been upgraded with on-site recording of temperature and precipitation, and auditory monitoring of other amphibian species. Continued research at Black Rock will be critical for understanding the interrelated effects of climate and disease on amphibians in the Greater Yellowstone Ecosystem.

We describe species richness and habitat associations of mayflies (Ephemeroptera) collected during amphibian surveys of 355 water bodies in Glacier National Park (NP), Montana, in 2006–2008. We collected 9 taxa (in 7 genera) of mayflies that were identifiable to species. Callibaetis ferrugineus hageni was collected most frequently, followed by Siphlonurus occidentalis, S. phyllis, Ameletus celer, A. similior, Parameletus columbiae, Ephemerella dorothea infrequens, Baetis bicaudatus, and Leptophlebia cupida. Siphlonurus phyllis had not been reported in the western United States prior to our surveys, and P. columbiae is a species of concern in the region. The identifications of 4 additional taxa were uncertain due to the poor condition of specimens found at only one site (Centroptilum sp. and Paraleptophlebia sp.) or because nymphal specimens could not be confidently identified (Cinygma sp. and Cinygmula sp.). Species richness of mayflies in wetlands seems low compared to that in streams and lakes in Glacier National Park. We found the most species of mayflies in beaver ponds, where we detected some species not commonly associated with lentic water bodies. Our survey was the first extensive survey of wetland invertebrates in Glacier NP and only the second that we are aware of in western Montana.

Our goals were to assess the statuses of amphibian populations relative to key environmental factors in Voyageurs National Park (VOYA), the St. Croix National Scenic Riverway (SACN), the Upper Mississippi River National Wildlife and Fish Refuge (UMR), and the Neal Smith National Wildlife Refuge (NS)and to inventory amphibian and reptile species in Voyageurs National Park (VOYA), the St. Croix National Scenic Riverway (SACN), and the Mississippi National River and Recreation Area (MISS).

We 1) conducted visual-encounter and call surveys for amphibians at potential breeding sites in VOYA, the SACN, the UMR, and the NS, and targeted searches for amphibians in the MISS, 2) conducted visual-encounter surveys for reptiles, especially turtles, in the vicinity of amphibian breeding sites in VOYA and the SACN, and to a lesser extent, the MISS, 3) analyzed amphibian survey data across management units and years using information-theoretic models to estimate occupancy and the probability of detection in relation to site-specific and sampling-specific characteristics, 4) sampled water from amphibian breeding sites in VOYA, the SACN, the UMR, and the NS and analyzed them for the presence of triazine herbicides, 5) measured gross physical deformities among amphibian metamorphs at breeding sites in VOYA, the SACN, the UMR, and the NS, and 6) sampled amphibian populations in VOYA, the SACN, and the UMR for the presence of pathogens, parasites, and symptoms of disease.

A summary of our principal results is as follows:

• We observed most of the amphibian and reptile species we expected to find in each management unit. We found 84%, 75%, 72%, 71%, and 31% of the amphibian species potentially present at SACN, NS, UMR, VOYA, and MISS (where we targeted fewer species and devoted less resources). Similarly, we observed 43% of the possible snakes and 67% of the possible lizards in the SACN and 75% of the possible snakes in VOYA. No lizards were likely in VOYA, and we did not observe any.

• Estimates of occupancy and probabilities of detection varied widely for amphibian species sampled during the day across VOYA, the SACN, the UMR, and the NS. Occupancy estimates ranged from https://0.29 (Pseudacris triseriata/maculata ) to https://0.79 (R. clamitans) with standard errors for occupancy from https://0.05 (R. clamitans) to 0.9 (Bufo americanus ). Ranges for the probabilities of detection were from https://0-0.34 (Bufo americanus ) to 0.18-1.0 (R. clamitans) with standard error ranges for detection probabilities from https://0-0.13 (R. clamitans) to 0-157.8 (Pseudacris crucifer ). Sampling-specific covariates that were influential in the best-fitted occupancy models were time, observer, and date. Similarly, site-specific covariates were management unit and habitat type.

• Of the 523 water samples we collected from amphibian breeding sites across management units and analyzed for the presence of triazines, 30.8% were below the detection limit of https://0.050 ppb, mostly in the SACN and VOYA. Fifty-five percent of the values above the detection limit also were above 0.1 ppb, a threshold shown to have caused deformed gonads in frogs in the laboratory in some studies; most of these were samples from the NS and UMR. The relative triazine concentrations across management units followed their proximity to extensive areas of row crops, where triazines are applied in large quantities. Triazine concentrations at breeding sites in the floodplain of the Mississippi River in the UMR fluctuated in association with the hydrograph of the Mississippi River.

• We observed gross physical deformities in less than 5% of the metamorphs sampled in VOYA, the SACN, the UMR, and the NS. The percentage of deformed metamorphs across all species for VOYA, the UMR, and the SACN from 2002-2005 ranged from 0.5% to 4.5%, and means for each of these management units across years were 1.5, 2.4, and 1.4%, respectively.

• We observed the potentially deadly chytrid fungus, Batrachochytrium dendrobatidis, on R. clamitans and R. septentrionalis from practically all sites where we sampled them in VOYA (88%) and the SACN (100%) during 2006, but at fewer sites on R. pipiens in the UMR (25%). The pattern was similar for these species in 2007, except we also sampled R. clamitans in the UMR. We observed B. dendrobatidis on R. clamitans and R. septentrionalis at most sites where we sampled them in VOYA (71%) and the SACN (67%), and the majority of sites where we sampled R. clamitans in the UMR (80%). In contrast, we observed B. dendrobatidis on R. pipiens at only 13% of the sites where we sampled them in VOYA, the SACN, and the UMR.

• Most individual, apparently healthy amphibians we submitted for health screening were afflicted with parasites of one sort or another, ranging from flukes to trematodes. Ribeiroia ondatrae, a parasitic trematode we observed, is considered a primary inducer of gross physical abnormalities in amphibians.

We sampled recently metamorphosed amphibians for the presence of Batrachochytrium dendrobatidis (Bd) at 75 unique breeding sites across five general areas within the north-central United States: 1) Voyageurs National Park (MN), 2) the St. Croix National Scenic Riverway (WI, MN), 3) the Upper Mississippi River National Wildlife and Fish Refuge (WI, MN, IA, IL), 4) northern Iowa, and 5) southwestern Wisconsin in 2006 and 2007. We swabbed individual metamorphs of nine amphibian species: Bufo americanus, Acris crepitans, the Hyla chrysoscelis-versicolor complex, Pseudacris triseriata, Rana catesbeiana, R. clamitans, R. septentrionalis, R. pipiens, and R. sylvatica using standard, clean methods and submitted the swabs to Pisces Molecular LLC (Boulder, Colorado) for PCR analyses. Bd was detected on at least one species at 34 of 75 sites (45%) and in 4 of the 5 general areas sampled. Bd was detected most often on R. clamitans (23 of 27 sites) and R. septentrionalis (7 of 9 sites) in relatively moderate to heavy quantities. The remaining detections also were on ranids, in relatively small quantities on R. pipiens (5 of 39 sites) and R. sylvatica (6 of 9 sites) and in moderate quantities on R. catesbeiana (1 of 2 sites). Bd was not detected on B. americanus, A. crepitans, H. chrysoscelis/versicolor, and P. triseriata.