Source: UNIVERSITY OF RHODE ISLAND submitted to
HABITAT CHARACTERISTICS OF POND-BREEDING AMPHIBIANS IN RHODE ISLAND
Sponsoring Institution
National Institute of Food and Agriculture
Project Status
TERMINATED
Funding Source
Reporting Frequency
Annual
Accession No.
0188375
Grant No.
(N/A)
Project No.
RI00319
Proposal No.
(N/A)
Multistate No.
(N/A)
Program Code
(N/A)
Project Start Date
Apr 1, 2001
Project End Date
Sep 30, 2004
Grant Year
(N/A)
Project Director
Paton, P. W.
Recipient Organization
UNIVERSITY OF RHODE ISLAND
19 WOODWARD HALL 9 EAST ALUMNI AVENUE
KINGSTON,RI 02881
Performing Department
NATURAL RESOURCE SCIENCES
Non Technical Summary
Pond-breeding amphibian populations are apparently declining, yet little is known about the effects of habitat fragmentation on these species. This project is designed to quantify the impact of habitat fragmentation on amphibians at multiple spatial scales.
Animal Health Component
80%
Research Effort Categories
Basic
20%
Applied
80%
Developmental
(N/A)
Classification

Knowledge Area (KA)Subject of Investigation (SOI)Field of Science (FOS)Percent
1350330107030%
1350850107020%
1350899107050%
Goals / Objectives
(1) At the local scale, (a) investigate the relationship between pond characteristics (both biotic and abiotic) and amphibian community structure, (b) quantify the relationship between amphibian community structure and the adjacent habitat attributes within 200 m of breeding ponds using a GIS approach. (2) At the metapopulation scale, (a) quantify the relationship between amphibian community structure at breeding ponds and habitat characteristics within 2 km, (b) determine site-fidelity and dispersal characteristics of adults and metamorphs for pond-breeding amphibians in the region, and (c) assess the impact of various types of potential dispersal barriers on pond-breeding amphibians.
Project Methods
For objective 1, I will use GIS to stratify the state into areas of low, medium, and high road density. I will then randomly select potential breeding ponds within each strata, then quantify amphibian community structure within ponds using egg mass counts, minnow traps, and dip net sweeps. Amphibian presence/absence will be compared to landscape structure surrounding breeding ponds at multiple spatial scales based on GIS and logistic regression analysis. For objective 2, this research would be conducted during years 3-5. I propose to monitor amphibian metapopulation dynamics at three clusters of ponds; one in a suburban area, one in a forested area fragmented by agriculture or turf, and one in an unfragmented forested area. The idea would be to monitor inter-pond dispersal among ponds in each landscape. This would be done using mark-recapture models and drift fence arrays.

Progress 04/01/01 to 09/30/04

Outputs
Biologists are increasingly interested in amphibians and their habitat requirements because recent research has documented population declines at a variety of spatial scales. Amphibians that breed in small, seasonal pools are vulnerable to habitat degradation and loss because breeding ponds and adjacent terrestrial habitats are often inadequately protected under existing federal and state wetland regulations. We examined the effectiveness of three sampling techniques (plot sampling, belt transect sampling, and cover board sampling) to quantify terrestrial habitat associations of pond-breeding amphibians during the 2002 and 2003 field seasons. Plot sampling, belt transect sampling, and cover board arrays had low capture rates and were only effective at detecting Eastern red-backed salamanders. Few pond-breeding amphibians were detected with these surface-sampling techniques; cover boards arrays were less expensive to implement than belt transect sampling or plot sampling. We used an information-theoretic approach (Akaike Information Criterion) to develop habitat models to predict amphibian occurrence based on surface sampling techniques. For pond-breeding species, the best models suggested that microhabitats with more downed coarse woody debris, greater leaf litter depth, and high numbers of vertical small mammal tunnels were selected. In 2003, we used radio-telemetry to assess the emigration behavior of 30 radio-implanted spotted salamanders on an active golf course, a golf course under construction, and a closed-canopy forest that served as a control site. The mean maximum dispersal distance from breeding ponds of spotted salamanders was 145 m (range 44 to 467 m). However, the maximum distance we documented was twice as far as previously published dispersal distances. Based on these dispersal distances, we calculated that a "life zone" of radius 185 m surrounding breeding ponds is needed to encompass 95% of the adult population. We used both an information-theoretic and a resource selection function approach (RSF) to develop habitat models to predict spotted salamander occurrence based on telemetry data. The best models predicted that spotted salamanders selected shaded habitats that provided a moist microclimate with high densities of vertical and horizontal small mammal burrows. RSF predicted that spotted salamanders selected forested wetlands to reside in during the spring and summer. Under current state law, only the basin for ponds <0.1 ha is regulated and no adjacent terrestrial habitat is protected. Given that a life zone of 185 m is needed to protect some species of pond-breeding amphibians, other conservation strategies will have to be implemented to insure the long-term viability of pond-breeding amphibian species in the state. This study suggests that maintaining extensive upland and wetland forested habitats near breeding ponds, with significant amounts of deep leaf litter, coarse woody debris, and high small mammal densities will help support pond-breeding amphibian populations in the future.

Impacts
This information will be of interest to wetland ecologists, conservation biologists, wildlife biologists, golf course superintenents, land managers, and land planners throughout New England. We have submitted this information to national peer-reviewed journals, industry publications (e.g., US Golf Association Green Section Record), and press releases to local and regional newspapers. We hope this information will be used to develop conservation strategies for pond-breeding amphibians in the region.

Publications

  • Montieth, K.E. and P.W.C. Paton. 2006. Emigration behavior of spotted salamanders on golf courses in southern Rhode Island. Journal of Herpetology. In press
  • Montieth, K.E. and P.W.C. Paton. 2006. Using Surface-based Sampling Techniques to Assess Pond-breeding Amphibian use of Terrestrial Habitats. Herpetological Review. In review


Progress 01/01/03 to 12/31/03

Outputs
Biologists are increasingly interested in amphibians and their habitat requirements because recent research has documented population declines at a variety of spatial scales. Amphibians that breed in small, seasonal pools are vulnerable to habitat degradation and loss because breeding ponds and adjacent terrestrial habitats are often inadequately protected under existing federal and state wetland regulations. We examined the effectiveness of three sampling techniques (plot sampling, belt transect sampling, and cover board sampling) to quantify terrestrial habitat associations of pond-breeding amphibians during the 2002 and 2003 field seasons. Plot sampling, belt transect sampling, and cover board arrays had low capture rates and were only effective at detecting Eastern red-backed salamanders. Few pond-breeding amphibians were detected with these surface-sampling techniques; cover boards arrays were less expensive to implement than belt transect sampling or plot sampling. We used an information-theoretic approach (Akaike Information Criterion) to develop habitat models to predict amphibian occurrence based on surface sampling techniques. For pond-breeding species, the best models suggested that microhabitats with more downed coarse woody debris, greater leaf litter depth, and high numbers of vertical small mammal tunnels were selected. In 2003, we used radio-telemetry to assess the emigration behavior of 30 radio-implanted spotted salamanders on an active golf course, a golf course under construction, and a closed-canopy forest that served as a control site. The mean maximum dispersal distance from breeding ponds of spotted salamanders was 145 m (range 44 to 467 m). However, the maximum distance we documented was twice as far as previously published dispersal distances. Based on these dispersal distances, we calculated that a "life zone" of radius 185 m surrounding breeding ponds is needed to encompass 95% of the adult population. We used both an information-theoretic and a resource selection function approach (RSF) to develop habitat models to predict spotted salamander occurrence based on telemetry data. The best models predicted that spotted salamanders selected shaded habitats that provided a moist microclimate with high densities of vertical and horizontal small mammal burrows. RSF predicted that spotted salamanders selected forested wetlands to reside in during the spring and summer. Under current state law, only the basin for ponds <0.1 ha is regulated and no adjacent terrestrial habitat is protected. Given that a life zone of 185 m is needed to protect some species of pond-breeding amphibians, other conservation strategies will have to be implemented to insure the long-term viability of pond-breeding amphibian species in the state. This study suggests that maintaining extensive upland and wetland forested habitats near breeding ponds, with significant amounts of deep leaf litter, coarse woody debris, and high small mammal densities will help support pond-breeding amphibian populations in the future.

Impacts
This information will be of interest to wetland ecologists, conservation biologists, wildlife biologists, golf course superintenents, land managers, and land planners throughout New England. We plan to publish this information national peer-reviewed journals, industry publications (e.g., US Golf Association Green Section Record), and press releases to local and regional newspapers. We hope this information will be used to develop conservation strategies for pond-breeding amphibians in the region.

Publications

  • Montieth, K.A. 2004. Terrestrial habitat use by pond-breeding amphibians in southern Rhode Island. M.S. thesis., Univ. of Rhode Island, Kingston, RI.
  • Egan, R. S., and P. W. C. Paton. 2004. Within-pond parameters affecting oviposition by wood frogs and spotted salamanders. Wetlands 24: 1-13.
  • Paton, P.W.C., R. S. Egan, J. E. Osenkowski, C. J. Raithel, and R. T. Brooks. 2003. Rana sylvatica (Wood Frog). Breeding behavior during drought. Herpetological Review 34:236-237.
  • Paton, P.W.C. and R.S. Egan. 2003. Strategies for maintaining pond-breeding amphibians on golf courses. Golf Course Management 71:90-94.
  • Paton, P.W.C. and R.S. Egan. 2003. Strategies to maintain amphibians on golf courses. USGA Green Section Record 41:27-31.


Progress 01/01/02 to 12/31/02

Outputs
There has been increasing interest in amphibians and their habitat requirements due to reports that their populations may be experiencing extensive declines and localized extinctions. Amphibians that breed in small, seasonal pools are of particular interest because this habitat is often inadequately protected under existing federal and state wetland regulations in the United States. There are thirteen species of amphibians that breed in seasonal ponds in southern New England. Both aquatic and terrestrial habitats are required by most amphibians in order to complete their complex life cycles. Most pond-breeding amphibians use breeding ponds for less than one month annually, and spend the majority of the year in adjacent wetlands and upland. Terrestrial habitat is crucial for pond-breeding amphibians because it provides food for growth and preparation for reproduction, and protection from predation, dehydration, and freezing. However, most studies of pond-breeding amphibians have emphasized their ecology within ponds during the breeding season. Semlitsch and Jenson (2001) recently highlighted the need to protect the surrounding terrestrial habitat - not only as a buffer zone for the ponds, but also as core habitat for the semi-aquatic animals that use the ponds. However, biologists must be able to define core habitat in order to protect it. Yet for pond-breeding amphibians, relatively little is known about their habitat requirements away from breeding ponds. Thus there is a pressing need to quantify habitat use patterns away from breeding ponds. The objectives of this study are to: (1) Assess a number of survey techniques to determine which are most effective in quantifying amphibian terrestrial habitat use (2) Quantify terrestrial habitat associations of pond-breeding amphibians during migration and the non-breeding season (3) Determine the spatial distribution of pond-breeding amphibians across the landscape (4) Determine if there are microhabitats within the upland landscape that could be considered `hot spots' of amphibian activity Fieldwork on upland habitat use patterns of pool-breeding amphibians was conducted during the 2002 field season. All 2002 field work was conducted at the proposed Shelter Harbor golf course, Westerly, Rhode Island. We used a variety of techniques (visual transect surveys, cover boards, and quadrant sampling) techniques to assess amphibian use of forested uplands and forested wetlands on the study site. These data were analyzed using an information-theoretic approach during fall 2002 to assess habitat associations in areas away from breeding pools. During the 2003 field season, we will use radio-telemetry to monitor movement of spotted salamanders away from breeding ponds.

Impacts
This information from this study will be of interest to conservation biologists throughout the country, as little is known about habitat use patterns of pool-breeding amphibians away from breeding ponds. Land managers (e.g., people interested in golf course construction and management) will be interested in the results of this research, as it will have important implications for management strategies for land in New England. Also, town planners, people interested in land acquistion and protection, would be very interested in the results of this research.

Publications

  • Paton, P. W. C. and W. B. Crouch, III. 2002. Using the phenology of pond-breeding amphibians to develop conservation strategies. Conservation Biology 16: 194-204.


Progress 01/01/01 to 12/31/01

Outputs
This project is designed to assess the impact of anthropogenic habitat change on pond-breeding amphibians in Rhode Island. During the 2001 field season, we completed field sampling some of 137 seasonally-flooded ponds randomly located throughout the state. Scott Egan, a M.S. candidate in NRS, completed his analyses of these data, which quantified a variety of vegetation and physical habitat characteristics within-ponds and also habitat characteristics (e.g., road density, residential development, amount of forested uplands and wetlands) within 1 km of breeding ponds. Scott completed his thesis in December 2001 and submitted two articles to peer-reviewed journals. During this same time period, a M.S. graduate student (Kate Monteith) was selected to initiate this research project for the 2002-2003 field seasons. The summer and fall was spent on study design and study site selection for the 2002 field season, which will focus on upland habitat characteristics used by pond-breeding amphibians.

Impacts
These data will be useful to conservation biologists, resource economists, land planners, and regulators interested in protecting biodiversity in Rhode Island. Based on initial analyses, the information collected by our research group will have national implications on vernal pool regulations.

Publications

  • Egan, R. S. 2001. Characteristics of amphibian breeding habitat and the adjacent landscape: Effects on two sympatric pond-breeding amphibians, Rana sylvatica and Ambystoma maculatum. M.S. Thesis, University of Rhode Island, Kingston RI.
  • Crouch, W. B. and P. W. C. Paton. 2000. Using egg-mass counts to monitor wood frog populations. Wildlife Society Bulletin 28:895-901.