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

Whit Gibbons

Professor of Ecology

University of Georgia

There is no accompanying Power Point.

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

This video and the slide show below it work together.
Stop and advance the slide show by clicking its controls at the top of its window.

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

This video and the slide show below it work together.
Stop and advance the slide show by clicking its controls at the top of its window.

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

This video and the slide show below it work together.
Stop and advance the slide show by clicking its controls at the top of its window.

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

This video and the slide show below it work together.
Stop and advance the slide show by clicking its controls at the top of its window.

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

This video and the slide show below it work together.
Stop and advance the slide show by clicking its controls at the top of its window.

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

This video and the slide show below it work together.
Stop and advance the slide show by clicking its controls at the top of its window.

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

This video and the slide show below it work together.
Stop and advance the slide show by clicking its controls at the top of its window.

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.

This video and the slide show below it work together.
Stop and advance the slide show by clicking its controls at the top of its window.

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

This video and the slide show below it work together.
Stop and advance the slide show by clicking its controls at the top of its window.

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.