Long-term Amphibian Studies, DAPTF, and PARC: A Natural Alliance

Whit Gibbons

Professor of Ecology

University of Georgia

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ABSTRACT

GIBBONS, WHIT
University of Georgia,Savannah River Ecology Laboratory, Aiken, SC
gibbons@srel.edu

Long-term Amphibian Studies, DAPTF, and PARC: A Natural Alliance

Research opportunities at the University of Georgia's Savannah River Ecology Laboratory (SREL) from 1951-2006 have provided an almost unprecedented situation for developing long-term ecological studies on amphibians. More than a half a century of data collection has led to findings and interpretations about disruption and abundance patterns that would not have been possible with shorter-term projects. The findings have implications to ecology and behavior of herptofauna that are directly related to conservation issues of interest to both DAPTF and PARC and that are necessary to address questions related to proper environmental management of wetland systems and their imprtance to regional amphibian biodiversity. Data from more than one million amphibians of more than 40 species reveal the importance of research continuity and funding in determining patterns and processes critical for making accurate scientific predictions and judicious land management decisions. Ecological interpretations based on short-term studies and short-sighted economic goals can lead to erroneous and costly conclusions that result in imprudent management decisions that could have been avoided if consistent study and longer-term information had been available.

Amphibian Population Status on NW California Landscapes: What is the Role of Anthropogenic Disturbance in Declines of Amphibians in No. California

Dr. Hartwell Welsh, Jr

Research Wildlife Ecologist

USDA Forest Service, PSW

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ABSTRACT

WELSH, HARTWELL H., JR.
USDA Forest Service, Pacific Southwest Research Station, Redwood Sciences Laboratory, Arcata, CA 95521
hwelsh@fs.fed.us

Amphibian Population Status on NW California Landscapes: What is the Role of Anthropogenic Disturbance in Declines of Amphibians in No. California

The herpetology grooup at the Redwood Sciences Lab, with assistance from the graduate students in the biology and wildlife departments at Humboldt State Univesity, has been studying the natural history, demography, and landscape ecology of amphibian assemblages in aquatic and terrestrial environments of Northern California for 21 years. A primary focus of our research has been to study the interactions between amphibian biology and human land management practices. In this talk I examine several interrelated themes that have emerged from this work. I discuss both individual species, and species assemblages, whose populaitons have declined on northern California's landscapes in response to anthropogenic natural resource management. Amphibian populations in this region have declined due to detrimental forestry practices, introductions of non-native predators, and manipulations of the natural flow regimes of north coast rivers. I review specific mechanisms that stress species by exceeding their physiological limits, and/or their fixed, evolved thresholds of ecological niche space, to explain three distinct regional amphibian population decline trajectories. I suggest possible modifications to these anthropogenic disturbance regimes that could help reverse on-going declines while still meeting human needs.

Challenges of Monitoring Headwater Amphibians: Searching for a Pattern Among the Warts

Lowell Diller

Green Diamond Resource Company

Korbel, California

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ABSTRACT

DILLER, LOWELL V., and LAURA L. BURKHOLDER
Green Diamond Resource Company, Korbel, CA
ldiller@greendiamond.com

Challenges of Monitoring Headwater Amphibians: Searching for a Pattern Among the Warts

As part of developing an aquatic habitat conservation plan on private timberlands, we attempted to use obligate headwater amphibian species to monitor potential impacts of timer harvest. Since 1997, we have been monitoring populations of southern torrent salamanders(Rhyacotriton variegatus) and coastal tailed frogs (Ascaphus truei). The goal was to compare changes in populations of these amphibians by employing a paired sub-basin design using randomly selected streams in sub-basins with (treatment) and without (control) timber harvest. The initial problem was to find a sufficient number of suitable streams with particular difficulty locating suitable control streams. To date, 30 and 18 monitoring reaches have been established for torrent salamanders and tailed frogs, respectively. Estimating relative abundance of torrent salamanders has proved problematic, because the process of searching for the animals appears to have lasting negative impacts on their habitat. The solutions may be a "lighter touch" survey approach and only attempting to determine presence/absence of salamanders. Estimating larval populations of tailed frogs has been successful, but high annual variation made interpreting the results problematic. In hopes of understanding this phenomenon, we began a mark-recapture study of post-metamorphic tailed frogs in 2002. The adults appear to be less variable compared to the larval populations, but it requires substantial effort to obtain a useful estimate through mark-recapture. The options are to have a large research budget that would allow an integrated approach to monitor both larvae and adult frogs or extend the larval monitoring to a longer interval (>10 years).

Population Parameters of Coastal Tailed Frogs in Northwestern California

Laura Burkholder

Green Diamond Resource Company

Korbel, California

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ABSTRACT

BURKHOLDER, LAURA L. and LOWELL V. DILLER
Green Diamond Resource Company, Korbel, CA
lburkholder@greendiamond.com

Population Parameters of Coastal Tailed Frogs in Northwestern California

Several studies have estimated the abundance of tailed frog (Ascaphus spp.) larvae within streams, but there has been no attempt to directly estimate the abundance of immature and adult frogs. We conducted a mark-recapture study of post-metamorphic coastal tailed frogs (A. truei) on a total of six streams from 2002-04 and used an open population model in Program MARK to estimate capture probabilities and population size within stream reaches. In 2003 probability of capture appeared to be constant over time (0.06 +- 0.01) and did not differ by age, sex, or creek. In 2004, capture probabilities of both creeks indicated a quadratic time trend depending on age (adults: mean = 0.11 +-0.02, immatures: mean = 0.13 +- 0.01) Captures were only adequate to estimate population size for two creeks during summer surveys from 2003 to 2004. Summer population estimates of females in both creeks indicated that there were on average 1.82 and 1.25 females per linear meter of stream in 2003 and 2004, respectively. Extrapolated to entire stream length with potential habitat, these estimates suggest potential total population sizes of 40,947 and 5,811 frogs for each creek. Our data indicated that tailed frogs have the potential to be a major biological component of headwater streams, but low capture probabilities limited our ability to estimate abundance for all streams. Because abundance estimates are important for management of this species, future studies should focus on methods that may increase capture probabilities in creeks with low population densities of frogs.

A New Alternative Method for Restraining Frogs

Ryan Bourque

Department of Biological Sciences

Humboldt State University

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ABSTRACT

BOURQUE, RYAN M.
Humboldt State University, Dept. of Biological Sciences, Arcata, CA
rmb32@humboldt.edu

A New Alternative Method for Restraining Frogs

Amphibian biologists use several different methods for marking adult anurans including toe clipping, PIT tags, visible implant elastomer, and radio transmitters. Employing such techniques requires maintaining control of study animals, which often entails field assistance or the use of anesthetics. Here, I will present an alternative method for restraining anurans that can be used in place of these conventional methods. This device, known as the "Ranid Restrainer", is inexpensive, durable, waterproof, easy to use and decontaminate, lightweight, and restrains frogs safely and quickly. After two years of field-testing, I have found this device to be an invaluable tool, especially when working alone, for marking small to medium sized ranid frogs.

Landscape-scale Risk Assessment for Current and Future UV-B Exposure of Alpine Amphibians of the Pacific Northwest

Wendy J. Palen

Department of Integrative Biology

University of California, Berkeley, CA

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ABSTRACT

PALEN, WENDY J.
Department of Integrative Biology, University of California, Berkeley, CA
wpalen@berkeley.edu

Landscape-scale Risk Assessment for Current and Future UV-B Exposure of Alpine Amphibians of the Pacific Northwest

Increasing ultraviolet-B radiation (UV-B, 290-320nm) as a result of stratospheric ozone depletion has been proposed as a leading explanation for declining amphibian populations for almost ten years. It is not until recently however that we have begun to examine the likelihood that UV-B could influence amphibians at the large spatial scales relevant to populations declines and species conservation. A key limitation to these has been in understanding how results from a variety of single experimental sites relate to the effect of UV-B more generally across many sites. Here I present the results of a series of field experiments testing the importance of UV-B exposure for the hatching success of two species of montane amphibians, Ambystoma macrodactylum and Rana cascadae, at sites spanning agradient of UV-B exposure. Using the existing variation in the concentration of UV-B attenuating optical color (dissolved organic matter, DOM) present in the water at different amphibian breeding sites, I find the ambient levels of UV-B only negatively affect amphibian egg survival in the clearest of sites when compared to embryos shielded from UV-B. Secondly, I used the level of UV-B exposure associated with significant mortality from these field experiments to evaluate the relevance of the total dose of UV-B received by embryos surveyed across a large number of montane breeding sites. By combining data onthe timing of incubation, measured incident UV-B, optical properties of the water, and the depth distribution and light exposure of embryos at each site I find that 0.4% of A. macrodactylum and 0% of R. cascadae embryos across a landscape of breeding sites are exposed to doses of UV-B exceeding lethal levels in our field experiments. These results and extend earlier predictions that ambient levels of UV-B are not likely to cause widespread embryonic mortality.

Reproductive Ecology and Breeding Migration Patterns of the Cascade's Frog (R. cascadae) in the Trinity Alps Wilderness, CA

Clara Wheeler

Department of Integrative Biology

US Forest Service, Pacific Southwest Research Station, Redwood Sciences Lab, Arcata, CA

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ABSTRACT

WHEELER, CLARA A., JUSTIN M. GARWOOD, and HARTWELL H. WELSH, JR.
US Forest Service, Pacific Southwest Research Station, Redwood Sciences Laboratory, Arcata, CA
cawheeler@fs.fed.us

Reproductive Ecology and Breeding Migration Patterns of the Cascade's Frog (Rana cascadae) in the Trinity Alps Wilderness, CA

Due to dramatic declines across the range of the Cascade's frog (Rana cascadae) in California, and recent genetic work suggesting that these frogs are of a distinct population segment, there has been increased interest in the conservation of the species resulting in a number of ongoing research projects. The purpose of our study was to obtain information regarding the species reproductive ecology and breeding migration patterns. We documented egg mass location, approximate date of breeding activity at each site, and movement to breeding sites based on mark-recapture data within Deep Creek Basin, Trinity Alps Wilderness, CA in 2003 thru 2005. In addition, we monitored male adult arrival time and breeding activity of frogs captured at one of the primary breeding sites within the basin. Breeding sites ranged 1,976 -2,226m in elevation with breeding activity occurring from the end of May through July within the basin. Our results indicate that R. cascadae are explosive breeders, however, the timing of breeding activity occurs later with increasing elevation (R2 = 0.49, N = 30, P < 0.0001). Of 213 ponds in the basin (at least 0.15m deep and 2-m2 surface area), 33 individual ponds were used for reproduction, but only 13 (6%) were used in all 3 years. We observed extensive movements to a breeding site used almost exclusively for reproduction (>1050m traveled) even when closer breeding sites were available. Our observations suggest that individuals can have high breeding site fidelity. We found a significant negative correlation between male frog size and arrival time to the breeding area in all years (Pearson, r = 0.40, N = 122, P < 0.0001).

Critically Low Numbers of Cascades Frog in the Lassen Region

Jonathan Stead

Graduate Group in Ecology, Univ. of California, Davis

Davis, California

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ABSTRACT

STEAD, JONATHAN, HARTWELL WELSH, and KAREN POPE
Graduate Group in Ecology, UC Davis, Davis, CA,

US Forest Service, Pacific Southwest Research Station, Redwood Sciences Laboratory, Arcata, CA.,steadje@yahoo.com

Critically Low Numbers of Cascades Frog in the Lassen Region

We conducted a cooperative inter-agency investigation into the status of native amphibians and nonnative fishes in lentic habitats at Lassen Volcanic National Park. Census surveys at Lassen Volcanic National Park were conducted during summer 2004, and results of surveys that we conducted in the Thousand Lakes and Caribou Wilderness areas during summer 2002 are also presented here. Visual encounter surveys were conducted to identify presence, species, life stage and relative abundance of amphibians, and timed gill net sets or visual surveys were used to identify fish presence, species, and relative abundance. Habitat data were also collected. We use generalized additive models to examine site attributes associated with amphibian occurrences, including the presence or absence of fish. Herpetofauna detected include the Pacific treefrog (Hyla regilla), western toad (Bufo boreas), long-toed salamander (Ambystoma macrodactylum), Cascades frog (Rana cascadae), rough-skinned newt (Taricha granulosa), western terrestrial garter snake (Thamnophis elegans), and the common garter snake (T. sirtalis). Fish species detected include three species of trout (Family: Salmonidae), five minnow species (Family: Cyprinidae), and the Tahoe sucker (Catostomus tahoensis). Our models suggest that populations of long-toed salamanders and Pacific treefrogs are less likely to be found in water bodies supporting fish. The Cascades frog was only detected at three sites, and could not be analyzed statistically. We believe that the Cascades frog is in immediate risk of extirpation from the Lassen region. Although fish clearly adversely affect palatable amphibian species, a number of considerations lead us to believe that fish are not the main driver behind the observed regional decline of Cascades frog. Factors outside the scope of this investigation may play an important role in declines observed in the Lassen region.

Aligning Northwest Herp Conservation Issues, Actions, and Funding: What's broken? How do we fix it? Where's the money?

Jeff Holmes

Co-chair Southeastern Partners in Amphibian and Reptile Conservation

Conservation Southeast, Inc.

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ABSTRACT

HOLMES, JEFF1*, PRIYA NANJAPPA-MITCHELL2, and ERNIE GARCIA3
1Partners in Amphibian and Reptile Conservation (PARC), co-chair, Southeastern PARC, and Conservation Southeast, Inc., conservationsoutheast@comcast.net; 2PARC State Agencies Coordinator, Gurnee, IL; 3PARC Federal Agencies Coordinator, US Fish and Wildlife Service, Weaverville, CA.

Aligning Northwest Herp Conservation Issues, Actions, and Funding: What's broken? How do we fix it? Where's the money?

Partners in Amphibian and Reptile Conservation (PARC) has developed a successful, multi-entity adaptive management model and organizational structure. PARC is deploying this model throughout its regional working groups. The model emphasizes communication and complementarity between technical working groups. This model is designed to optimize applied conservation biology and minimize resource expenditures that do not meaningfully impact wild populations and their habitats. In this model, partners affiliate themselves with one or more technical working groups based on their individual skills and interests. The model then provides a vehicle for the coordinated flow of knowledge, funding, and other resources between "Information Gathering" working groups (Research, Inventory/Monitoring) and "Implementation" working groups (Management, Education/Outreach, Policy/Trade) in order to maximize the net conservation impact of every penny and every drop of sweat.

The Endangered Arroyo Toad: How is It Doing?

Clayton Creed

U.S. Fish and Wildlife Service

Ventura, CA

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ABSTRACT

CREED, CLAYTON
US Fish & Wildlife Service, Ventura, CA, creed_clayton@fws.gov

The Endangered Arroyo Toad: How is It Doing

The arroyo toad was listed as endangered under the Federal Endangered Species Act in 1994 because research showed it had been extirpated from approximately 75% of previously occupied habitat. Although a number of drainages containing arroyo toads had been identified at that time, only eight were thought to contain viable populations. Since it was listed, a few previously undetected arroyo toad populations have been located and a number of threats to the species have been addressed. However, other populations appear to have been extirpated or turned out to be misidentified toads of another species. About one half of the approximately 30 currently known arroyo toad populations appear relatively secure in the near term. Many areas occupied by the arroyo toad are protected to a large degree; however, there are also areas vulnerable to expanding human pressures where some level of habitat degradation continues to occur.

Separate and Combined Effects of Nitrate and Pathogenic Water Mold Saprolegnia on Survival of Amphibian Larvae

John M. Romansic, Kristin A. Diez, Elise M. Higashi,

and Andrew R. Blaustien


Department of Zoology

Oregon State University

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ABSTRACT

ROMANSIC, JOHN*, KRISTIN DIEZ, ELISE HIGASHI, and ANDREW BLAUSTEIN. Department of Zoology, Oregon State University, Corvallis, OR, romansij@science.oregonstate.edu

Separate and Combined Effects of Nitrate and the Pathogenic Water Mold Saprolegnia on Survival of Amphibian Larvae

Synergisms between stressors and infectious organisms can have important effects on host organisms. Nitrate pollution is an environmental stressor of global significance. We tested for a synergism between nitrate and Saprolegnia, a pathogenic water mold, using larvae of three amphibian species: Ambystoma gracile (northwestern salamander), Hyla regilla (Pacific treefrog) and Rana cascadae (Cascades frog). Each species was tested separately, using a fully factorial experiment with three nitrate addition treatments and two Saprolegnia treatments. Nitrate treatments had nominal nitrate concentrations of 0, 5, and 20 mg/L. Saprolegnia treatments were three hemp seeds laden with Saprolegnia (Saprolegnia treatment) and three sterile hemp seeds (control treatment). Each experiment lasted for one week. No significant effects of nitrate addition or Saprolegnia were found on survival of H. regilla. In contrast, survival of R. aurora was affected by an interaction between Saprolegnia and nitrate. With no nitrate, survival of R. aurora was significantly lower in the Saprolegnia treatment compared to the control treatment. However, there were no significant effects of the Saprolegnia treatment on survival when nitrate was added. A. gracile followed a pattern similar to R. aurora, but the difference between the Saprolegnia treatment and the control treatment when nitrate was not added was not significant, nor was there a significant nitrate by Saprolegnia interaction. Our results suggest that nitrate addition and Saprolegnia had less-than-additive effects on R. aurora survival. Less-than-additive interactions between stressors and infectious organisms have been described in other systems. Future studies should attempt to determine what controls the nature of interactions between stressors and infectious organisms.

Hybridization between Native California tiger salamanders and Non-native Tiger Salamanders: Developing Management Strategies

William McIver

U.S. Fish and Wildlife Service

Ventura, CA

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ABSTRACT

McIVER, WILLIAM R.
U.S. Fish and Wildlife Service, Ventura, California 93003, bill_mciver@fws.gov

Hybridization between Native California tiger salamanders (Ambystoma californiense) and Non-native Tiger Salamanders (Ambystoma tigrinum): Developing Management Strategies

The California tiger salamander (Ambystoma californiense) is federally listed as endangered in Sonoma and Santa Barbara Counties, and threatened in central California. Non-native barred tiger salamanders (Ambystoma tigrinum mavortium) were introduced into central California as fishing bait in the mid-1900s. The threat of hybridization with non-native tiger salamanders is particularly severe in the Central Coast Range and Bay Area regions, and, to a lesser extent, the Central Valley region. Hybridization between species may lead to introgression, which occurs when hybrid individuals repeatedly backcross to one or both parental types so that genetic material is transferred between the two species. Natural hybridization can be an important component of evolutionary processes; however, hybridization and introgression can be cause for concern, particularly if they are the result of human activities such as the introduction of non-native taxa. Management strategies regarding hybridization in native California tiger salamanders need to be developed through cooperation between Federal and State agencies, researchers, consultants, and private landowners.

An Update on Frogs, Contaminants, and Disease Research

POWERPOINT AND VIDEO WITHHELD AT SPEAKER'S REQUEST

FELLERS, GARY M.
USGS Western Ecological Research Center, Point Reyes National Seashore, Point Reyes, CA,
gary_fellers@usgs.gov

An Update on Frogs, Contaminants, and Disease Research

A fungal disease (chytridiomycosis), first described in 1999 and possibly introduced from Africa, has been closely associated with amphibian die-offs in the Sierra Nevada and elsewhere, but it is not clear whether the chytrid fungus is a primary cause of the declines or whether it gets a foothold when amphibian populations are under stress. Chytrid fungus in Yosemite National Park was reported in Rana muscosa in 2001 (Fellers et al.). In 2005, I began a detailed study of two watersheds in Yosemite and one at Point Reyes National Seashore to determine the distribution of chytrid fungus in native amphibian tadpoles. In a series of related studies, data from contaminants research suggest that pesticides are playing a significant role in amphibian declines in the Sierra Nevada. Studies comparing contaminants levels in frog and tadpole tissue with concentrations in sediment, air, snow, and water in coastal and mountain regions of California strongly support the view that contaminants are playing a significant role in amphibian declines.

Effects of Density on Batrachochytrium dendrobatidis Transmission in Mountain Yellow-legged Frogs (Rana muscosa)

Lara Rachowicz

Resource Management and Science,

Yosemite National Park, Yosemite, CA

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ABSTRACT

RACHOWICZ, LARA1,2*, and CHERIE BRIGGS2
1Resources Management and Science, Yosemite National Park, Yosemite, CA, lara_rachowicz@nps.gov; 2Dept. of Integrative Biology, Univ. of California, Berkeley, CA.

Effects of Density on Batrachochytrium dendrobatidis Transmission in Mountain Yellow-legged Frogs (Rana muscosa).

An emerging infectious disease of amphibians, chytridiomycosis, caused by the fungal pathogen Batrachochytrium dendrobatidis, recently has been implicated in population declines and possible extinctions throughout the world, including in protected areas. B. dendrobatidis zoospores, the infectious stage of the fungus, infect keratinized cells found in the mouthparts of anuran tadpoles and the skin of postmetamorphic individuals. Here, we examined the form of the transmission function of this pathogen in the mountain yellow-legged frog (Rana muscosa) by performing laboratory and field experiments. We then used a maximum likelihood approach to determine what form of the transmission function is best supported by the experimental data. We also investigated what impact crowding might have had on transmission. In the laboratory and in some natural environments, we detected a significant positive relationship in the proportion of R. muscosa tadpole hosts that became infected after a few weeks of B. dendrobatidis exposure with increasing numbers of previously infected R. muscosa tadpoles added to their local environment.

Dilemmas in Amphibian Management: Disease and Translocation, a Group Discussion

Dawne Becker

California Dept. of Fish and Game

Eastern Sierra and Inland Deserts Region, Bishop, CA

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ABSTRACT

BECKER, DAWNE
California Department of Fish & Game, Eastern Sierra and Inland Deserts Region, Bishop, CA, dbecker@dfg.ca.gov

Dilemmas in Amphibian Management: Disease and Translocation, a Group Discussion

Researchers and managers working on draft conservation strategies for Sierra Nevada amphibians focused on many issues, including identification of threats, feasibility of conducting restoration projects, the potential need for translocations, and genetics. Conservative management actions were recommended to avoid genetic manipulations, but at the time, disease was not suspected as having such a large role with regard to restoration and management. We now know otherwise. The focus will be on generating a group discussion on amphibian relocations and their value—in the presence of disease—to ascertain whether or not managers should continue Rana muscosa (RaMu)-specific restoration/translocation projects in areas where the nearest Ramu populations have been infected with chytridiomycosis. Although other researchers and agencies are facing the same dilemma, a regional California Department of Fish & Game project was the impetus for this discussion. While most of our past and ongoing restoration projects have occurred where an adjacent RaMu population would benefit without active translocation, we now have a newly-fishless water with no adjacent RaMu. We are awaiting the verdict, but suspect that disease has infected the only RaMu populations within the same basin. Do we continue with translocations, possibly extending the range of the disease? Do we discontinue translocations, but wait for further knowledge that may guide us appropriately? Will the public, and just as importantly, USFWS, support restoration projects that result in fishless waters without nearby frog populations and without immediate plans for translocation? Will disease persist if infected tadpoles are transferred into new waters? Initial results by Vredenberg’s group (see poster), indicate that non-infected tadpoles transplanted into fishless waters formerly occupied by frogs, but extirpated by disease, have survived without contracting chytrid. Do we have other options that may benefit both amphibians and science? We’re testing for Chytrid (and using methods that reduce the likelihood of us spreading it), but irido- and rana-viruses are present in the Sierra Nevada. How do we deal with this, and perhaps other undetected hitchhikers? While assuming that there is not just one “right” answer, it would be much appreciated to hear the combined professional opinions of the group.

Rana boylii Plasticity and Management Under Dam-controlled Flows in the Northern West-slope Sierra Nevada

Ryan Peek

Stillwater Sciences

Berkeley, CA

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ABSTRACT

PEEK, RYAN*, and SAPNA B. KHANDWALA
Stillwater Sciences, Berkeley, CA 94705, ryan@stillwatersci.com

Rana boylii Plasticity and Management Under Dam-controlled Flows in the Northern West-slope Sierra Nevada

Rana boylii (foothill yellow-legged frog) populations are found throughout the foothills of the Sierra Nevada, often occurring downstream of large dams that control flows for much of the year. Renewal of hydroelectric project licenses generally requires studies of project-related effects on surrounding ecosystems, to help inform the design of flow schedules that are consistent with species conservation and management.
Focused studies conducted in support of hydro-relicensing generally occur in two phases and are designed to fill gaps in our understanding of species ecology and potential responses to altered flows. The first phase is focused on local distribution and basic life history timing of R. boylii. The second phase focuses on a specific analysis of how the hydroelectric project may potentially affect the species, including habitat connectivity and the effects of regulated flows on breeding habitat. Based on case studies on the South Fork Feather and South Fork American rivers, results of first phase investigations have validated current research on R. boylii habitat use and local distribution in similar watersheds. In addition, our observations suggest R. boylii can occur in atypical habitats (man-made tunnels over a mile from the main channel, within roadside culverts, and along the banks of reservoirs).
Studies in the second phase, however, are generally more complex and ask more detailed ecological questions. We need an integrated, efficient approach that can maximize our understanding of flow effects on R. boylii (within the hydroelectric project relicensing time frame), that furthers both scientific research and overall species management goals.

Evaluating the Accuracy of Different Monitoring Designs by Subsampling a 14-Year R. boylii Eggmass Census

Sarah J. Kupferberg

Quest Engineering Corp.

Point Richmond, CA

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ABSTRACT

KUPFERBERG, SARAH J.1, and WENDY J. PALEN2
1Quest Engineering Corp., Point Richmond, CA, skupferberg@pacbell.net; 2Department of Integrative Biology, University of California, Berkeley, CA

Evaluating the Accuracy of Different Monitoring Designs by Subsampling a 14-Year R. boylii Eggmass Census.

Rana boylii eggmass surveys have been conducted annually on a 5 km reach of the South Fork Eel River (Mendocino Co., CA) since 1992. These detailed spatial and temporal data provide the opportunity to evaluate the consequences of choosing among a variety of sampling strategies for estimating 1) site occupancy, and 2) population trends through time. Such choices are often made by managers of regulated rivers. For the purposes of hydroelectric dam relicensing utilities and regulators are faced with the task of determining species distributions and site occupancy over very long reaches, (up to 50 river miles). Further, they must monitor the status of populations to detect long term trends and decide whether to invoke adaptive management of flow regime. We evaluated the effects of specific spatial and temporal sampling biases which reflect potential real world constraints. For example, over the life of a 30 year dam license, censusing of R. boylii may only occur periodically, e.g. once every five years, or selectively at populous breeding sites located in proximity to large tributary confluences. We find that the underlying spatial and temporal pattern in R. boylii breeding strongly influences the accuracy of monitoring, because nearly 50% of the population breeds within one riffle-pool sequence of perennial tributary confluences consistently across years. One of the consequences of this pattern is that if surveys and monitoring efforts solely focused on these sites, we would overestimate both the population size and population stability through time. In the absence of a priori knowledge about the longitudinal distribution of individuals (e.g. a full reach survey) it would be unlikely to accurately capture the spatial and temporal dynamics of R. boylii populations.

Climatic and Water Flow Triggers Assoc. With Breeding and Movement in a Foothill Yellow-legged Frog Population on the North Fork Feather River,CA

Joseph E. Drennan

Garcia and Associates

San Francisco, CA

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DRENNAN, JOSEPH E*, RONALD JACKMAN, KARLA R. MARLOW, and KEVIN D. WISEMAN.
Garcia and Associates (GANDA), San Francisco, CA, jed@garciaandassociates.com

Climatic and Water Flow Triggers Associated With Breeding and Movement in a Foothill Yellow-legged Frog (Rana boylii) Population on the North Fork Feather River, California

We conducted visual encounter surveys and radio telemetry of R. boylii within six tributaries and associated breeding sites of the regulated North Fork Feather River (NFFR; Butte Co., California) in 2004-2005. Local environmental data (tributary/river temperature, tributary/river flow, air temperature, precipitation) was collected from data loggers, a local weather station, and hydroelectric gages. Using chin and flank patterns to identify individuals, we collected movement data on 476 individual frogs including 47 individuals that were captured both years. Frogs showed high site fidelity within tributaries to the NFFR, which act as refugia for frogs during the non-breeding season. Initial movements to the NFFR were triggered by day length, and male frogs left tributaries earlier than females and stayed longer at breeding sites. Females moved at more than twice the rate of males (♀= 58.1 m/day) and covered distances up to 1,899 m in ≤ 6 days for a maximum movement rate of 316.5 m/day. Once at the river, frogs initiated breeding when mainstem water temperatures were ≥10 °C and mainstem flow was ≤ 55% of baseflow, on a descending hydrograph. Length of stay by females at river breeding sites was determined by flow level and sex ratio. While males commonly utilized mainstem breeding sites adjacent to the confluence of “home” tributaries, several males made considerable river movements to breeding sites adjacent to other tributaries.

Lessons Learned ..... While Doing Maintenance Activities Where There Are California Red-legged Frogs

Jennifer Hogan

California Department of Water Resources

Sacramento, CA

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ABSTRACT

HOGAN, JENNIFER
California Department of Water Resources, Sacramento, CA, jhogan@water.ca.gov

Lessons Learned ..... While Doing Maintenance Activities Where There Are California Red-legged Frogs

Maintenance activities within the Department of Water Resources Delta Field Division’s ponds and drainages have provided some opportunities and challenges for DWR Environmental Scientists. Regulatory agencies, handling techniques, habitat determination, and survey results have all provided us with a chance for further understanding. Learning to deal effectively with the regulatory agencies was the first challenge. Handling California red-legged frogs and tadpoles in a safe and reliable manner provided another learning opportunity. Learning to determine red-legged frog habitat also proved to be interesting, since we discovered these frogs in areas where we initially did not expect them to be. The most exciting lesson learned, though, is that the work we are doing in these drainages appears to be good for the frogs. DWR is now entering its fourth year of these maintenance activities. We will undoubtedly learn more lessons as we continue our work. Hopefully, we will also continue to benefit this threatened frog.

(Meta)population Dynamics of a Threatened Native Amphibian, Rana draytonii

Antonia D'Amore

Department of Ecology and Evolutionary Biology

University of California, Santa Cruz

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ABSTRACT

D’AMORE, ANTONIA
Dept. of Ecology and Evolution, University of California, Santa Cruz, CA, damore@biology.ucsc.edu

(Meta)population Dynamics of a Threatened Native Amphibian, Rana draytonii

Building off of work done with the Elkhorn Slough National Estuarine Research Reserve (ESNERR), I am working with two different populations of the California Red-legged Frog, Rana draytonii. One population is located at ESNERR, spread throughout 5 different ponds. The other is on privately owned land with the frogs inhabiting 15 different ponds. I am currently conducting a mark/recapture study using PIT tags in order to estimate interannual survivorship and transition rates between the different ponds. I intend to use this data to build a simple metapopulation model that will describe their movement. In addition to this work, I am radio-tracking a sub-set of the frogs to look at their upland habitat usage and to obtain detailed information about their dispersal routes between ponds. This will potentially allow me to incorporate the effects of matrix habitat type into the model.

Another part of my research focuses on indirect interactions between Rana draytonii and its invasive competitor and predator, Rana catesbeiana, the American Bullfrog. I focus specifically on changes in microhabitat usage within the ponds, and in breeding behavior.

Phylogeography of Hydromantes shastae: Implications for Management

Robert E. Bingham

Department of Integrative Biology

University of California, Berkeley, CA

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ABSTRACT

BINGHAM, ROBERT E.
Department of Integrative Biology, University of California, Berkeley, CA, rbingham@berkeley.edu

Phylogeography of Hydromantes shastae: Implications for Management

The utility of phylogeographic analyses in conservation and management has increased dramatically with the development of molecular and analytic methods. When different molecular markers and statistical approaches yield congruent results, we are able to properly characterize distinct evolutionary lineages and identify divergent populations for management. One application of phylogeography to management is to identify species with restricted ranges and high levels of genetic divergence between lineages, indicating significant isolation. The Shasta Salamander, Hydromantes shastae, is a geographically restricted plethodontid species exhibiting remarkable evolutionary diversification at small spatial scales. New and previously collected tissue samples from throughout the known range of the species were sequenced for the mitochondrial cytochrome b and 16S genes. Bayesian phylogenetic analyses showed statistically supported clades with large divergences between lineages. In two different pairwise comparisons, samples two miles apart were 4.5% divergent in the cytochrome b gene, indicating remarkably high levels of genetic differentiation. Unpublished allozyme data were previously collected for a subset of these populations, and have now been analyzed using multidimensional scaling and population structure software. With relatively high estimates of Nei’s genetic distance and fixed allozyme differences, the nuclear data strongly support significant isolation and diversification at small spatial scales. Analyses of both mitochondrial and nuclear markers show Hydromantes shastae to be strongly structured across its restricted range, and highlight several divergent populations and lineages that should be of high priority in management actions aimed at preserving evolutionary history and potential in this unique species.

The Effect of Habitat Quality on Genetic Diversity in a Riparian Frog Species (Rana boylii)

Jennifer A. Dever

Biology Department., University of San Francisco

San Francisco, CA

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ABSTRACT

DEVER, JENNIFER A.
Biology Department., University of San Francisco, San Francisco, CA, jadever@usfca.edu

The Effect of Habitat Quality on Genetic Diversity in a Riparian Frog Species (Rana boylii)

Amphibian populations are declining at an alarming rate. Therefore gathering data on existing populations is critical for their proper management. One species that is of concern is the foothill yellow-legged frog (Rana boylii), a river-dwelling amphibian whose historic range has been reduced over 66%. A population existing along the Eel River in northern California was surveyed. This river runs through an area that includes both near-pristine and impacted habitat. For this study, sampling from both regions was conducted. Using molecular markers, the level of genetic variability amongst individuals collected from 13 different tributaries branching off the Eel River was completed. Results indicate that habitat quality has an impact on genetic diversity in this species. Such information is extremely useful for conservation management purposes.

Effects of Fish Stocking and Fish Removal on Cascades Frogs (Rana cascadae) and Other Native Species

Karen L. Pope

Ecology Graduate Group & Entomology Dept, UC Davis

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ABSTRACT

POPE, KAREN L.1,2*, SHARON P. LAWLER1, AND HART W. WELSH2
1Ecology Graduate Group & Entomology Dept, UC Davis, kpope@ucdavis.edu; 2U.S. Forest Service Pacific SW Research Station, Redwood Sciences Laboratory.

Effects of Fish Stocking and Fish Removal on Cascades Frogs (Rana cascadae) and Other Native Species

We have completed three years of a four-year study testing the effects of introduced trout on the flow of insect and amphibian prey from lakes to predators in uplands. We are studying 4 historically fishless 'reference' basins, and 12 'treatment' basins under three management schemes: trout stocking, suspended stocking, and fish removals. Lakes are at elevations over 1,920 m in the Trinity Alps of California. In summer, 2003 we collected biweekly pre-treatment data at all basins, and in fall we initiated treatments. Sites are being re-sampled in summers 2004-6. We are surveying amphibians, snakes, aquatic insects, bats, and birds. The aquatic fauna did not differ among the three treatments before fish removal, but Cascades frogs, garter snakes and large-bodied insects were more numerous in reference lakes. In 2004 and 2005, recruitment of Cascades frogs, Pacific treefrogs and large aquatic insects improved dramatically in fish removal lakes. Preliminary results will be presented that focus on changes in amphibian populations and distributions across treatments during the first three years of the project.