Evaluating the functional importance of secretive species: A case study of aquatic snake predators in isolated wetlands
Abstract
Abstract Although the need to prioritize limited conservation resources has prompted increased interest in understanding the functional importance of species within ecosystems, species that are infrequently observed are often written off as being unimportant. In this study, we use aquatic snakes as a case study for examining the importance of secretive predators. Most snakes are extremely cryptic and secretive, traits that not only lead to the perception that they are rare, and of minor importance, but also impede attempts to quantify densities. We used high sampling effort and robust‐design capture–recapture analyses to estimate density of aquatic snakes inhabiting an isolated 5.4‐ha wetland in South Carolina, USA . We assessed snake diets and coupled field measurements of growth rates with laboratory‐derived data on mass conversion efficiency to estimate prey consumption by snakes over a 1‐year period. We found a peak density 171 snakes ha −1 of wetland habitat, corresponding to a standing biomass of 7.77 kg ha −1 . We calculated that snakes within the wetland consumed a total of over 200 kg (>55 000 individuals) of amphibian prey annually, translating into >150 000 kJ ha −1 of energy flow from secondary to tertiary consumers within the wetland food web. Further, because many amphibians are primarily terrestrial asmore »
- Authors:
-
- Department of Biological Sciences University of Arkansas Fayetteville AR 72701 USA, Savannah River Ecology Laboratory University of Georgia Aiken SC 29802 USA
- Savannah River Ecology Laboratory University of Georgia Aiken SC 29802 USA
- Publication Date:
- Sponsoring Org.:
- USDOE
- OSTI Identifier:
- 1401644
- Grant/Contract Number:
- DE‐FC09‐07SR22506
- Resource Type:
- Publisher's Accepted Manuscript
- Journal Name:
- Journal of Zoology
- Additional Journal Information:
- Journal Name: Journal of Zoology Journal Volume: 298 Journal Issue: 4; Journal ID: ISSN 0952-8369
- Publisher:
- Wiley-Blackwell
- Country of Publication:
- United Kingdom
- Language:
- English
Citation Formats
Willson, J. D., and Winne, C. T. Evaluating the functional importance of secretive species: A case study of aquatic snake predators in isolated wetlands. United Kingdom: N. p., 2015.
Web. doi:10.1111/jzo.12311.
Willson, J. D., & Winne, C. T. Evaluating the functional importance of secretive species: A case study of aquatic snake predators in isolated wetlands. United Kingdom. https://doi.org/10.1111/jzo.12311
Willson, J. D., and Winne, C. T. Tue .
"Evaluating the functional importance of secretive species: A case study of aquatic snake predators in isolated wetlands". United Kingdom. https://doi.org/10.1111/jzo.12311.
@article{osti_1401644,
title = {Evaluating the functional importance of secretive species: A case study of aquatic snake predators in isolated wetlands},
author = {Willson, J. D. and Winne, C. T.},
abstractNote = {Abstract Although the need to prioritize limited conservation resources has prompted increased interest in understanding the functional importance of species within ecosystems, species that are infrequently observed are often written off as being unimportant. In this study, we use aquatic snakes as a case study for examining the importance of secretive predators. Most snakes are extremely cryptic and secretive, traits that not only lead to the perception that they are rare, and of minor importance, but also impede attempts to quantify densities. We used high sampling effort and robust‐design capture–recapture analyses to estimate density of aquatic snakes inhabiting an isolated 5.4‐ha wetland in South Carolina, USA . We assessed snake diets and coupled field measurements of growth rates with laboratory‐derived data on mass conversion efficiency to estimate prey consumption by snakes over a 1‐year period. We found a peak density 171 snakes ha −1 of wetland habitat, corresponding to a standing biomass of 7.77 kg ha −1 . We calculated that snakes within the wetland consumed a total of over 200 kg (>55 000 individuals) of amphibian prey annually, translating into >150 000 kJ ha −1 of energy flow from secondary to tertiary consumers within the wetland food web. Further, because many amphibians are primarily terrestrial as adults and are consumed by aquatic snakes only when they return to wetlands to breed, snakes can be responsible for substantial transfer of energy and biomass between terrestrial and aquatic habitats. Our study is one of the first comprehensive evaluations of the importance of snakes as predators and underscores the need to consider snakes in initiatives aimed at preserving overall ecosystem integrity.},
doi = {10.1111/jzo.12311},
journal = {Journal of Zoology},
number = 4,
volume = 298,
place = {United Kingdom},
year = {Tue Dec 29 00:00:00 EST 2015},
month = {Tue Dec 29 00:00:00 EST 2015}
}
https://doi.org/10.1111/jzo.12311
Web of Science
Works referenced in this record:
The Influence of Functional Diversity and Composition on Ecosystem Processes
journal, August 1997
- Tilman, D.
- Science, Vol. 277, Issue 5330
Vulnerability of Cambodian water snakes: Initial assessment of the impact of hunting at Tonle Sap Lake
journal, October 2007
- Brooks, Sharon E.; Allison, Edward H.; Reynolds, John D.
- Biological Conservation, Vol. 139, Issue 3-4
Rare species loss alters ecosystem function - invasion resistance
journal, July 2001
- Lyons, Kelly G.; Schwartz, Mark W.
- Ecology Letters, Vol. 4, Issue 4
Garter Snake Population Dynamics from a 16-Year Study: Considerations for Ecological Monitoring
journal, February 2005
- Lind, Amy J.; Welsh, Hartwell H.; Tallmon, David A.
- Ecological Applications, Vol. 15, Issue 1
Energy Flow and Nutrient Cycling in Salamander Populations in the Hubbard Brook Experimental Forest, New Hampshire
journal, August 1975
- Burton, Thomas M.; Likens, Gene E.
- Ecology, Vol. 56, Issue 5
Stoichiometry of nutrient recycling by vertebrates in a tropical stream: linking species identity and ecosystem processes
journal, March 2002
- Vanni, Michael J.; Flecker, Alexander S.; Hood, James M.
- Ecology Letters, Vol. 5, Issue 2
Income breeding allows an aquatic snake Seminatrix pygaea to reproduce normally following prolonged drought-induced aestivation
journal, November 2006
- Winne, Christopher T.; Willson, John D.; Gibbons, J. Whitfield
- Journal of Animal Ecology, Vol. 75, Issue 6
Severe mammal declines coincide with proliferation of invasive Burmese pythons in Everglades National Park
journal, January 2012
- Dorcas, M. E.; Willson, J. D.; Reed, R. N.
- Proceedings of the National Academy of Sciences, Vol. 109, Issue 7
Empirical Tests of Biased Body Size Distributions in Aquatic Snake Captures
journal, June 2008
- Willson, John D.; Winne, Christopher T.; Keck, Michael B.
- Copeia, Vol. 2008, Issue 2
Remarkable Amphibian Biomass and Abundance in an Isolated Wetland: Implications for Wetland Conservation
journal, October 2006
- Gibbons, J. Whitfield; Winne, Christopher T.; Scott, David E.
- Conservation Biology, Vol. 20, Issue 5
Ecology of a Low-Energy Specialist: Food Habits and Reproductive Biology of the Arafura Filesnake (Acrochordidae)
journal, May 1986
- Shine, Richard
- Copeia, Vol. 1986, Issue 2
Trophic Downgrading of Planet Earth
journal, July 2011
- Estes, James A.; Terborgh, John; Brashares, Justin S.
- Science, Vol. 333, Issue 6040
Estimates of Prey Consumption and Trophic Impacts of Cetaceans in the USA Northeast Continental Shelf Ecosystem
journal, January 1997
- Kenney, R. D.; Scott, G. P.; Thompson, T. J.
- Journal of Northwest Atlantic Fishery Science, Vol. 22
A Capture-Recapture Design Robust to Unequal Probability of Capture
journal, July 1982
- Pollock, Kenneth H.
- The Journal of Wildlife Management, Vol. 46, Issue 3
The Global Decline of Reptiles, Déjà Vu Amphibians
journal, January 2000
- Gibbon, J. Whitfield; Scott, David E.; Ryan, Travis J.
- BioScience, Vol. 50, Issue 8
Biological Delineation of Terrestrial Buffer Zones for Pond-Breeding Salamanders
journal, October 1998
- Semlitsch, Raymond D.
- Conservation Biology, Vol. 12, Issue 5
Population size and Recovery Criteria of the Threatened lake erie Watersnake: Integrating Multiple Methods of Population Estimation
journal, January 2006
- King, Richard B.; Queral-Regil, Alejandro; Stanford, Kristin M.
- Herpetological Monographs, Vol. 20, Issue 1
The effects of amphibian population declines on the structure and function of Neotropical stream ecosystems
journal, February 2006
- Whiles, Matt R.; Lips, Karen R.; Pringle, Cathy M.
- Frontiers in Ecology and the Environment, Vol. 4, Issue 1
Making Great Leaps Forward: Accounting for Detectability in Herpetological Field Studies
journal, December 2007
- Mazerolle, Marc J.; Bailey, Larissa L.; Kendall, William L.
- Journal of Herpetology, Vol. 41, Issue 4
Evaluation of trap capture in a geographically closed population of brown treesnakes on Guam
journal, February 2009
- Tyrrell, Claudine L.; Christy, Michelle T.; Rodda, Gordon H.
- Journal of Applied Ecology, Vol. 46, Issue 1
On the Ecological Roles of Salamanders
journal, December 2004
- Davic, Robert D.; Welsh, Hartwell H.
- Annual Review of Ecology, Evolution, and Systematics, Vol. 35, Issue 1
Prey morphology constrains the feeding ecology of an aquatic generalist predator
journal, March 2011
- Willson, John D.; Hopkins, William A.
- Ecology, Vol. 92, Issue 3
Erratum: Estimating Temporary Emigration Using Capture-Recapture Data with Pollock's Robust Design
journal, October 1997
- Kendall, William L.
- Ecology, Vol. 78, Issue 7
Energy flow and subsidies associated with the complex life cycle of ambystomatid salamanders in ponds and adjacent forest in southern Illinois
journal, October 2005
- Regester, Kurt J.; Lips, Karen R.; Whiles, Matt R.
- Oecologia, Vol. 147, Issue 2
Do predators control prey species abundance? An experimental test with brown treesnakes on Guam
journal, May 2012
- Iii, Earl W. Campbell; Adams, Amy A. Yackel; Converse, Sarah J.
- Ecology, Vol. 93, Issue 5
Seasonal variation in terrestrial resource subsidies influences trophic niche width and overlap in two aquatic snake species: a stable isotope approach
journal, February 2010
- Willson, John D.; Winne, Christopher T.; Pilgrim, Melissa A.
- Oikos, Vol. 119, Issue 7
Food Web Complexity and Species Diversity
journal, January 1966
- Paine, Robert T.
- The American Naturalist, Vol. 100, Issue 910
Biology and Impacts of Pacific Island Invasive Species. 2. Boiga irregularis, the Brown Tree Snake (Reptilia: Colubridae) 1
journal, July 2007
- Rodda, Gordon H.; Savidge, Julie A.
- Pacific Science, Vol. 61, Issue 3
Estimating Detection Probability Parameters for Plethodon Salamanders Using the Robust Capture–Recapture Design
journal, January 2004
- Bailey, Larissa L.; Simons, Theodore R.; Pollock, Kenneth H.
- Journal of Wildlife Management, Vol. 68, Issue 1
Anguilliform fishes and sea kraits: neglected predators in coral-reef ecosystems
journal, November 2006
- Ineich, I.; Bonnet, X.; Brischoux, F.
- Marine Biology, Vol. 151, Issue 2
Ecological and methodological factors affecting detectability and population estimation in elusive species
journal, January 2011
- Willson, John D.; Winne, Christopher T.; Todd, Brian D.
- The Journal of Wildlife Management, Vol. 75, Issue 1
Innovative Methods for Studies of Snake Ecology and Conservation
book, May 2009
- Dorcas, Michael E.; Willson, John D.
- Snakes
Predation as a Regulating Factor on Small Rodent Populations in Southern Sweden
journal, January 1983
- Erlinge, Sam; Göransson, Görgen; Hansson, Lennart
- Oikos, Vol. 40, Issue 1
Response of Brown Treesnakes to Reduction of Their Rodent Prey
journal, January 2007
- Gragg, James E.; Rodda, Gordon H.; Savidge, Julie A.
- Journal of Wildlife Management, Vol. 71, Issue 7
Foraging Ecology of the Striped Swamp Snake, Regina alleni, in Southern Florida
journal, February 1980
- Godley, J. Steve
- Ecological Monographs, Vol. 50, Issue 4
Functional and Numerical Responses of Predators: Where Do Vipers Fit in the Traditional Paradigms?
journal, October 2008
- Nowak, Erika M.; Theimer, Tad C.; Schuett, Gordon W.
- Biological Reviews, Vol. 83, Issue 4