Geology Reports⌕ Search

Geology topics

M. J. Adams

Publications and source records attributed to M. J. Adams.

At least 55 records · Page 3Linked to original sources

Columbia spotted frog (Rana luteiventris) in southeastern Oregon: A survey of historical localities, 2009

The Columbia spotted frog (Rana luteiventris) occupies a large range in western North America and is comprised of at least three genetic units. Concern exists regarding the status of the Great Basin populations in Oregon, Idaho, and Nevada. We surveyed target and nearby alternate sites on public lands in southeastern Oregon where there was evidence that Columbia spotted frogs were historically present. We found the species at 59.5 percent (25 of 42) of target or nearby alternate sites. They were in 15 of 23 permanent streams and 8 of 13 intermittent streams. Our surveys do not provide evidence of widespread population losses in our sites. Interpretation of status of Columbia spotted frogs in this study is limited by a lack of precision in some of the historical locations and by our inability to determine if locations where only adults were indicated in the historical record once had breeding populations. Our results support the need for continued investigation of these populations.

Open-File Report↗

Short-term effect of cattle exclosures on Columbia Spotted Frog (Rana luteiventris) populations and habitat in northeastern Oregon

Livestock grazing is a common land use across the western United States, but concerns have been raised regarding its potential to affect amphibian populations. We studied the short-term effects of full and partial livestock grazing exclosures on Rana luteiventris (Columbia Spotted Frog) populations using a controlled manipulative field experiment with pre- and posttreatment data (2002–2006). Despite a significant increase in vegetation height within grazing exclosures, we did not find treatment effects for egg mass counts, larval survival, or size at metamorphosis 1–2 years following grazing exclosure installation. Water samples taken in late summer showed concentrations of nitrite, nitrate, ammonia, and orthophosphate that were low or near detection limits across all ponds and years. The results of this experiment do not support a hypothesis that limiting cattle access to breeding ponds will help conserve R. luteiventris populations in our study area. Further research is needed to evaluate regional variation and long-term effects of grazing exclosures on R. luteiventris populations.

Journal of Herpetology↗

A Protocol for Aging Anurans Using Skeletochronology

Age distribution information can be an important part of understanding the biology of any population. Age estimates collected from the annual growth rings found in tooth and bone cross sections, often referred to as Lines of Arrested Growth (LAGs), have been used in the study of various animals. In this manual, we describe in detail all necessary steps required to obtain estimates of age from anuran bone cross sections via skeletochronological assessment. We include comprehensive descriptions of how to fix and decalcify toe specimens (phalanges), process a phalange prior to embedding, embed the phalange in paraffin, section the phalange using a microtome, stain and mount the cross sections of the phalange and read the LAGs to obtain age estimates.

Open-File Report↗

Occurrence of the amphibian pathogen Batrachochytrium dendrobatidis in Pacific Northwestern USA

Chytridiomycosis (infection by the fungus Batrachochytrium dendrobatidis ) has been associated with amphibian declines in at least four continents. We report results of disease screens from 210 pond-breeding amphibians from 37 field sites in Oregon and Washington. We detected B. dendrobatidis on 28% of sampled amphibians, and and we found - > 1 detection of B. dendrobatidi s from 43% of sites. Four of seven species tested positive for B. dendrobatidis , including the Northern Red-Legged Frog ( Rana aurora ), Columbia Spotted Frog ( Rana luteiventris ), and Oregon Spotted Frog ( Rana pretiosa ). We also detected B. dendrobatidis in nonnative American Bullfrogs ( Rana catesbeiana ) from six sites in western and central Oregon. Our study and other recently published findings suggest that B. dendrobatidis has few geographic and host taxa limitations among North American anurans. Further research on virulence, transmissibility, persistence, and interactions with other stressors is needed to assess the potential impact of B. dendrobatidis on Pacific Northwestern amphibians.

Oregon↗

Oregon Spotted Frog (Rana pretiosa) movement and demography at Dilman Meadow: Implications for future monitoring

From 2001 to 2005, we studied the demography and seasonal movement of Oregon spotted frogs (Rana pretiosa) translocated into created ponds in Dilman Meadow in central Oregon. Our objectives were to inform future monitoring and management at the site, and to elucidate poorly known aspects of the species’ population ecology. Movement rates revealed complementary use of sites seasonally, with one small spring being preferred during winter that was rarely used during the rest of the year. Growth rates were significantly higher in ponds that were not used for breeding, and larger size resulted in significantly higher survival. When variation in survival by size was accounted for there was little variation among ponds in survival. Seasonal estimates of survival were lowest for males during the breeding/post-breeding redistribution period, suggesting a high cost of breeding for males. Overwintering survival for both genders was relatively high. Our study supports others in suggesting Oregon spotted frogs are specific in their overwintering habitat requirements, and that predator-free springs may be of particular value. We suggest that any future monitoring include measures of the rate of pond succession. Demographic monitoring should include metrics of both frog reproduction and survival: counts of egg masses at all ponds during spring, and capture-recapture study of survival in mid and late summer when capture rates are highest. Additional study of early life stages would be particularly useful to broaden our understanding of the species’ ecology. Specifically, adding intensive capture and marking effort after larval transformation in fall would enable a full understanding of the annual life cycle. Complete study of the annual life cycle is needed to isolate the life stages and mechanisms through which Oregon spotted frogs are affected by stressors such as nonnative predators. Dilman Meadow, which lacks many hypothesized stressors, is an important reference for isolating the life stages most responsive to management elsewhere in the species’ range.

Open-File Report↗

Characteristics of Columbia spotted frog (Rana luteiventris) oviposition sites in northeastern Oregon, USA

Several western ranid frogs possess a unique strategy of breeding communally over a short temporal window and reusing oviposition sites between years. However, little is published on the characteristics of oviposition sites selected by these explosive breeders. The Columbia spotted frog ( Rana luteiventris ) is native to northwestern North America and is of conservation concern in the southern portions of its range. As part of a study examining relationships between livestock grazing and R. luteiventris habitat, we assessed characteristics of the species' oviposition sites in 25 fishless ponds in northeastern Oregon. Oviposition sites were generally in shallow water (<25 cm) close to shore and tended to be in the northeastern portion of ponds. Oviposition sites were found more frequently over heavily vegetated substrates and in areas of less substrate slope and shade than random points in littoral zones. We did not quantify temperature differences within ponds, but the patterns we documented are consistent with preferential use of warmer microhabitats for oviposition.

Western North American Naturalist↗

Taxonomic and geographic variation in oviposition by tailed frogs ( Ascaphus spp )

Tailed frogs ( Ascaphus spp.) oviposit in cryptic locations in streams of the Pacific Northwest and Rocky Mountains. This aspect of their life history has restricted our understanding of their reproductive ecology. The recent split of A. montanus in the Rocky Mountains from A. truei was based on molecular differentiation, and comparisons of their ecology are limited. Our objectives were to provide a range-wide summary of information on Ascaphus oviposition, compare some aspects of the reproductive ecology of the 2 species, and examine geographic variation in their reproductive traits. Reproductive ecology of the 2 species differed. Ascaphus truei had smaller clutches, oviposited later in the summer, and had a longer duration of oviposition than A. montanus . A greater number of communal oviposition sites were attributed to A. montanus . These ecological differences support the recent taxonomic revision of Ascaphus and suggest that different management strategies may be necessary for each species where conservation is a priority.

Northwestern Naturalist↗

Integrating bioavailability approaches into waste rock evaluations

The presence of toxic metals in soils affected by mining, industry, agriculture and urbanization, presents problems to human health, the establishment and maintenance of plant and animal habitats, and the rehabilitation of affected areas. A key to managing these problems is predicting the fraction of metal in a given soil that will be biologically labile, and potentially harmful ('bioavailable'). The molecular form of metals and metalloids, particularly the uncomplexed (free) form, controls their bioavailability and toxicity in solution. One computational approach for determining bioavailability, the biotic ligand model (BLM), takes into account not only metal complexation by ligands in solution, but also competitive binding of hardness cations (Ca 2+,Mg 2+,) and metal ions to biological receptor sites. The more direct approach to assess bioavailability is to explicitly measure the response of an organism to a contaminant. A number of microbial enzyme tests have been developed to assess the impact of pollution in a rapid and procedurally simple way. These different approaches in making bioavailability predictions may have value in setting landuse priorities, remediation goals, and habitat reclamation strategies.

Conference Paper↗

Estimated ultraviolet radiation doses in wetlands in six national parks

Ultraviolet-B radiation (UV-B, 280&ndash;320-nm wavelengths) doses were estimated for 1024 wetlands in six national parks: Acadia (Acadia), Glacier (Glacier), Great Smoky Mountains (Smoky), Olympic (Olympic), Rocky Mountain (Rocky), and Sequoia/Kings Canyon (Sequoia). Estimates were made using ground-based UV-B data (Brewer spectrophotometers), solar radiation models, GIS tools, field characterization of vegetative features, and quantification of DOC concentration and spectral absorbance. UV-B dose estimates were made for the summer solstice, at a depth of 1 cm in each wetland. The mean dose across all wetlands and parks was 19.3 W-h m &minus;2 (range of 3.4&ndash;32.1 W-h m &minus;2 ). The mean dose was lowest in Acadia (13.7 W-h m &minus;2 ) and highest in Rocky (24.4 W-h m &minus;2 ). Doses were significantly different among all parks. These wetland doses correspond to UV-B flux of 125.0 &mu;W cm &minus;2 (range 21.4&ndash;194.7 &mu;W cm &minus;2 ) based on a day length, averaged among all parks, of 15.5 h. Dissolved organic carbon (DOC), a key determinant of water-column UV-B flux, ranged from 0.6 (analytical detection limit) to 36.7 mg C L &minus;1 over all wetlands and parks, and reduced potential maximal UV-B doses at 1-cm depth by 1%&ndash;87 %. DOC concentration, as well as its effect on dose, was lowest in Sequoia and highest in Acadia (DOC was equivalent in Acadia, Glacier, and Rocky). Landscape reduction of potential maximal UV-B doses ranged from zero to 77% and was lowest in Sequoia. These regional differences in UV-B wetland dose illustrate the importance of considering all aspects of exposure in evaluating the potential impact of UV-B on aquatic organisms.

Acadia National Park, Glacier National Park, Great↗

Distribution patterns of lentic-breeding amphibians in relation to ultraviolet radiation exposure in western North America

An increase in ultraviolet-B (UV-B) radiation has been posited to be a potential factor in the decline of some amphibian population. This hypothesis has received support from laboratory and field experiments showing that current levels of UV-B can cause embryo mortality in some species, but little research has addressed whether UV-B is influencing the distribution of amphibian populations. We compared patterns of amphibian presence to site-specific estimates of UV-B dose at 683 ponds and lakes in Glacier, Olympic, and Sequoia&ndash;Kings Canyon National Parks. All three parks are located in western North America, a region with a concentration of documented amphibian declines. Site-specific daily UV-B dose was estimated using modeled and field-collected data to incorporate the effects of elevation, landscape, and water-column dissolved organic carbon. Of the eight species we examined ( Ambystoma gracile, Ambystoma macrodactylum, Bufo boreas, Pseudacris regilla, Rana cascadae, Rana leuteiventris, Rana muscosa, Taricha granulosa ), two species ( T. granulosa and A. macrodactylum ) had quadratic relationships with UV-B that could have resulted from negative UV-B effects. Both species were most likely to occur at moderate UV-B levels. Ambystoma macrodactylum showed this pattern only in Glacier National Park. Occurrence of A. macrodactylum increased as UV-B increased in Olympic National Park despite UV-B levels similar to those recorded in Glacier. We also found marginal support for a negative association with UV-B for P. regilla in one of the two parks where it occurred. We did not find evidence of a negative UV-B effect for any other species. Much more work is still needed to determine whether UV-B, either alone or in concert with other factors, is causing widespread population losses in amphibians.

California, Montana, Washington↗

Amphibian Research and Monitoring Initiative (ARMI): A successful start to a national program in the United States

Most research to assess amphibian declines has focused on local-scale projects on one or a few species. The Amphibian Research and Monitoring Initiative (ARMI) is a national program in the United States mandated by congressional directive and implemented by the U.S. Department of the Interior (specifically the U.S. Geological Survey, USGS). Program goals are to monitor changes in populations of amphibians across U.S. Department of the Interior lands and to address research questions related to amphibian declines using a hierarchical framework of base-, mid- and apex-level monitoring sites. ARMI is currently monitoring 83 amphibian species (29% of species in the U.S.) at mid- and apex-level areas. We chart the progress of this 5-year-old program and provide an example of mid-level monitoring from 1 of the 7 ARMI regions.

Applied Herpetology↗

Sampling protocol for monitoring abiotic and biotic characteristics of mountain ponds and lakes

This document describes field techniques and procedures used for sampling mountain ponds and lakes. These techniques and procedures will be used primarily to monitor, as part of long-term programs in National Parks and other protected areas, the abiotic and biotic characteristics of naturally occurring permanent montane lentic systems up to 75 ha in surface area. However, the techniques and procedures described herein also can be used to sample temporary or ephemeral montane lentic sites. Each Standard Operating Procedure (SOP) section addresses a specific component of the limnological investigation, and describes in detail field sampling methods pertaining to parameters to be measured for each component.

Techniques and Methods↗

Amphibian occurrence and aquatic invaders in a changing landscape: Implications for wetland mitigation in the Willamette Valley, Oregon

Despite concern about the conservation status of amphibians in western North America, few field studies have documented occurrence patterns of amphibians relative to potential stressors. We surveyed wetland fauna in Oregon's Willamette Valley and used an information theoretic approach (AIC) to rank the associations between native amphibian breeding occurrence and wetland characteristics, non-native aquatic predators, and landscape characteristics in a mixed urban-agricultural landscape. Best predictors varied among the five native amphibians and were generally consistent with life history differences. Pacific tree frog (Pseudacris regilla) and long-toed salamander (Ambystoma macrodactylum) occurrence was best predicted by the absence of non-native fish. Northern red-legged frog (Rana a. aurora) and northwestern salamander (Ambystoma gracile) were most strongly related to wetland vegetative characteristics. The occurrence of rough-skinned newts (Taricha granulosa), a migratory species that makes extensive use of terrestrial habitats, was best predicted by greater forest cover within 1 km. The absence of non-native fish was a strong predictor of occurrence for four of the five native species. In contrast, amphibians were not strongly related to native fish presence. We found little evidence supporting negative effects of the presence of breeding populations of bullfrog (Rana catesbeiana) on any native species. Only the two Ambystoma salamanders were associated with wetland permanence. Northwestern salamanders (which usually have a multi-year larval stage) were associated with permanent waters, while long-toed salamanders were associated with temporary wetlands. Although all the species make some use of upland habitats, only one (rough-skinned newt) was strongly associated with surrounding landscape conditions. Instead, our analysis suggests that within-wetland characteristics best predict amphibian occurrence in this region. We recommend that wetland preservation and mitigation efforts concentrate on sites lacking non-native fish for the conservation of native amphibians in the Willamette Valley and other western lowlands.

Wetlands↗

Evidence of decline for Bufo boreas and Rana luteiventris in and around the northern Great Basin

A method is described for the analysis of polychlorinated biphenyl (PCB) compounds in tissue samples. Cleanup by hexane-aceto-nitrile partitioning and Florisil column chromatography are performed on samples before oxidative treatment to convert DDE to DCBP. PCB components are then determined semi-quantitatively by TLC. No prior separation of PCB from chlorinated pesticides is required. The lower limit of sensitivity is 0.2 ?g.

Alytes↗

Optical characteristics of natural waters protect amphibians from UV-B in the U.S. Pacific Northwest: Reply

Few ecologists would dispute that exposure to high levels of ultraviolet-B radiation (UV-B) is detrimental to organisms. It is well established that UV-B has been a critical factor shaping the physiology ( Blum et al. 1949 , Hansson 2000 ), behavior ( Pennington and Emlet 1986 , van de Mortel and Buttemer 1998 ), and distribution ( Williamson et al. 2001 , Leavitt et al. 2003 ) of many aquatic species. Recently, increasing UV-B caused by stratospheric ozone depletion has stimulated much research on the UV-B sensitivity of a wide variety of taxa, and has been found to cause direct mortality ( Calkins and Thordardottir 1980 , reviewed by Siebeck et al. 1994 ), elevate developmental abnormalities ( Ankley et al. 2002 ), increase susceptibility to disease ( Little and Fabacher 1994 , Kiesecker and Blaustein 1995 ), and change the strength of species interactions ( Sommaruga 2003 ). Increasing levels of UV-B have also been invoked as an explanation for the decline of some amphibian species, and support for this hypothesis has been extrapolated from many laboratory experiments and field studies at individual sites that indicate ambient or enhanced levels of UV-B can increase mortality of embryos and larvae (but see Licht 2003 ). This has been an especially attractive hypothesis for amphibian populations in alpine environments where direct anthropogenic impacts such as habitat modification are limited and ambient levels of UV-B are high ( Blaustein and Wake 1990 , Blaustein et al. 1994 , Alford and Richards 1999 ). However, for all the attention UV-B has received in the context of declining amphibian populations, there is little evidence linking the physiological sensitivity of individuals to actual population dynamics ( Licht 2003 ).

California, Oregon, Washington↗

Wetland management for amphibians in the Willamette Valley

Introduction In the past two decades, scientists around the world have increasingly noted losses of amphibian populations. Many of these declines have occurred in protected areas like national parks, where the causes mostly remain mysterious. However, in multipleuse landscapes, resource managers frequently face more obvious conservation problems and must make decisions that will affect amphibians. The purpose of this fact sheet is to present recent findings pertinent to wetland management and amphibians in a multiple-use landscape.

Fact Sheet↗

Indirect facilitation of an anuran invasion by non-native fishes

Positive interactions among non-native species could greatly exacerbate the problem of invasions, but are poorly studied and our knowledge of their occurrence is mostly limited to plant-pollinator and dispersal interactions. We found that invasion of bullfrogs is facilitated by the presence of co-evolved non-native fish, which increase tadpole survival by reducing predatory macroinvertebrate densities. Native dragonfly nymphs in Oregon, USA caused zero survival of bullfrog tadpoles in a replicated field experiment unless a non-native sunfish was present to reduce dragonfly density. This pattern was also evident in pond surveys where the best predictors of bullfrog abundance were the presence of non-native fish and bathymetry. This is the first experimental evidence of facilitation between two non-native vertebrates and supports the invasional meltdown hypothesis. Such positive interactions among non-native species have the potential to disrupt ecosystems by amplifying invasions, and our study shows they can occur via indirect mechanisms.

Ecology Letters↗