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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.

Counts of egg masses have been proposed as a valid state variable for monitoring Wood Frog (Rana sylvatica) populations. Here, we investigate the statistical power of egg mass counts to identify trends in egg mass abundance using computer simulation. We also calculate the expected bias in using the slope of a trend line fit to a time series of egg mass counts as an estimate of trend in abundance. The results of the simulations suggest that a minimum of eight years of monitoring is necessary to achieve high statistical power for monitoring programs that use counts of Wood Frog egg masses as a state variable. In addition, the slope of a trend line fit to a time series of egg mass counts is a biased estimate of trend in abundance. Increasing the duration of monitoring, however, minimizes the bias and improves inference regarding trend. Managers and herpetologists who plan to monitor Wood Frog populations using counts of egg masses should plan on a minimum of eight years of data collection to have high power to detect trends.

Although populations of amphibians are declining worldwide, there is no evidence that salamanders occupying small streams are experiencing enigmatic declines, and populations of these species seem stable. Theory predicts that dispersal through multiple pathways can stabilize populations, preventing extinction in habitat networks. However, empirical data to support this prediction are absent for most species, especially those at risk of decline. Our mark-recapture study of stream salamanders reveals both a strong upstream bias in dispersal and a surprisingly high rate of overland dispersal to adjacent headwater streams. This evidence of route-dependent variation in dispersal rates suggests a spatial mechanism for population stability in headwater-stream salamanders. Our results link the movement behavior of stream salamanders to network topology, and they underscore the importance of identifying and protecting critical dispersal pathways when addressing region-wide population declines.

I examined the population dynamics of a high elevation population of the pond-breeding amphibian Rana luteiventris. Understanding the natural dynamics of this species in relation to environmental variation informs us about the natural history of this species, helps identify how different environmental stressors may impact the population, and may elucidate key processes important to other populations of the same species or other species inhabiting mountain environments.

Non?native fish and bullfrogs (Lithobates catesbeianus) are frequently cited as contributing to the decline of ranid frogs in the western United States, so we hypothesized that non?native species, habitat, or a combination of these relate to the probability of local extinction for northern red?legged frogs (Rana aurora) in Oregon, USA. We also hypothesized that the probability of colonization relates to land use, wetland size, or riparian forest. In a 5?yr study, we found no support for an effect of non?native species on northern red?legged frogs. Instead, probability of local extinction decreased with the extent of emergent vegetation and riparian forest. This finding suggests that managers consider the role of habitat when confronting non?native species problems.

In 2003, southern California experienced several large fires that burned thousands of hectares of wildlife habitats and conserved lands. To investigate the effects of these fires on the reptile and
amphibian communities, we compared the results from prefire herpetofauna and vegetation sampling to two years of postfire sampling across 38 burned and 17 unburned plots. The sampling plots were spread over four vegetation types and four open space areas within San Diego County. Our capture results indicated that burned chaparral and coastal sage scrub plots lost herpetofaunal species diversity after the fires and displayed a significant shift in overall community structure. Shrub and tree cover at the burned plots, averaged across the second and third postfire years, had decreased by 53% in chaparral and 75% in coastal sage scrub. Additionally, postfire herpetofauna community structure at burned plots was more similar to that found in unburned grasslands. In grassland and woodland/riparian vegetation plots, where shrub and tree cover was not significantly affected by fires, we found no differences in the herpetofaunal species diversity or community composition. At the individual species level, Sceloporus occidentalis was the most abundant reptile in these areas both before and after the fires. We saw increases in the net capture rates for several lizard species, including Aspidoscelis tigris, Phrynosoma coronatum, and Uta stansburiana in burned chaparral plots and Aspidoscelis hyperythra and U. stansburiana in burned coastal sage scrub plots. The toad, Bufo boreas, was detected at significantly fewer burned plots in chaparral after the fires. Additionally, we documented decreases in the number of plots occupied by lizards (Elgaria multicarinata), salamanders(Batrachoseps major), and snakes (Coluber constrictor, Lampropeltis getula, Pituophis catenifer, andMasticophis lateralis) in coastal sage scrub and chaparral after the fires. We discuss the individual species results as they relate to such life-history traits as the susceptibility to initial mortality, the response to the altered postfire habitat, and shifts in the availability of potential prey. We foresee that a continued unnatural fire regime will result in a simplification of the southern California reptile and amphibian communities.