, 28:585 | Cite as

Methods for estimating the amount of vernal pool habitat in the northeastern United States

  • Robin Van Meter
  • Larissa L. Bailey
  • Evan H. Campbell Grant


The loss of small, seasonal wetlands is a major concern for a variety of state, local, and federal organizations in the northeastern U.S. Identifying and estimating the number of vernal pools within a given region is critical to developing long-term conservation and management strategies for these unique habitats and their faunal communities. We use three probabilistic sampling methods (simple random sampling, adaptive cluster sampling, and the dual frame method) to estimate the number of vernal pools on protected, forested lands. Overall, these methods yielded similar values of vernal pool abundance for each study area, and suggest that photographic interpretation alone may grossly underestimate the number of vernal pools in forested habitats. We compare the relative efficiency of each method and discuss ways of improving precision. Acknowledging that the objectives of a study or monitoring program ultimately determine which sampling designs are most appropriate, we recommend that some type of probabilistic sampling method be applied. We view the dual-frame method as an especially useful way of combining incomplete remote sensing methods, such as aerial photograph interpretation, with a probabilistic sample of the entire area of interest to provide more robust estimates of the number of vernal pools and a more representative sample of existing vernal pool habitats.

Key Words

abundance estimation adaptive cluster sampling dual frame vernal pools wetlands 

Literature Cited

  1. Alpizar-Jara, R., K. H. Pollock, and D. E. Haines. 2005. Markrecapture estimators for dual frame population size of prominent nesting structures: the effect of uncertain detection probability. Environmental and Ecological Statistics 12: 155–68.CrossRefGoogle Scholar
  2. Armstrong, D. P. 2005. Integrating the metapopulation and habitat paradigms for understanding broad-scale declines of species. Conservation Biology 19: 1402–10.CrossRefGoogle Scholar
  3. Brooks, R. T., J. Stone, and P. Lyons. 1998. An inventory of seasonal forest ponds on the Quabbin Reservoir watershed, Massachusetts. Northeastern Naturalist 5: 219–30.CrossRefGoogle Scholar
  4. Brown, J. A. 2003. Designing an efficient adaptive cluster sample. Environmental and Ecological Statistics 10: 95–105.CrossRefGoogle Scholar
  5. Burne, M. R. 2001. Massachusetts aerial photo survey of potential vernal pools. Natural Heritage and Endangered Species Program, Department of Fisheries and Wildlife, Westborough, MA, USA.Google Scholar
  6. Burne, M. R. and R. G. Lathrop. 2008. Remote and field identification of vernal pools. p. 55–68, In A. J. K. Calhoun and P. K. deMaynadier (eds.) Science and Conservation of Vernal Pools in Northeastern North America. CRC Press, Boca Raton, FL, USA.Google Scholar
  7. Calhoun, A. J. K. and P. K. deMaynadier (eds.). 2007. Science and Conservation of Vernal Pools in Northeastern North America. CRC Press, Boca Raton, FL, USA.Google Scholar
  8. Calhoun, A. J. K., T. E. Walls, S. S. Stockwell, and M. McCollough. 2003. Evaluating vernal pools as a basis for conservation strategies: a Maine case study. Wetlands 23: 70–81.CrossRefGoogle Scholar
  9. DiMauro, D. and M. L. Hunter, Jr. 2002. Reproduction of amphibians in natural and anthropogenic temporary pools in managed forests. Forest Science 48: 397–406.Google Scholar
  10. Goldberg, N. A., J. N. Heine, and J. A. Brown. 2007. The application of adaptive cluster sampling for rare subtidal macroalgae. Marine Biology 151: 1343–48.CrossRefGoogle Scholar
  11. Grant, E. H. C. 2005. Correlates of vernal pool occurrence in the Massachusetts, USA landscape. Wetlands 25: 480–87.CrossRefGoogle Scholar
  12. Haines, D. E. and K. H. Pollock. 1998. Estimating the number of active and successful bald eagle nests: an application of the dual frame method. Environmental and Ecological Statistics 5: 245–56.CrossRefGoogle Scholar
  13. Julian, J. T., C. D. Snyder, and J. A. Young. 2006. The use of artificial impoundments by two amphibian species in the Delaware Water Gap National Recreation Area. Northeast Naturalist 13: 459–68.CrossRefGoogle Scholar
  14. Lathrop, R. G., P. Montesano, J. Tesauro, and B. Zarate. 2005. Statewide mapping and assessment of vernal pools: a New Jersey case study. Journal of Environmental Management 76: 230–38.CrossRefPubMedGoogle Scholar
  15. MacKenzie, D. I., J. D. Nichols, J. A. Royle, K. H. Pollock, L. L. Bailey, and J. E. Hines. 2006. Occupancy Estimation and Modeling: Inferring Patterns and Dynamics of Species Occurrence. Academic Press, New York, NY, USA.Google Scholar
  16. Marsh, D. M. and P. C. Trenham. 2001. Metapopulation dynamics and amphibian conservation. Conservation Biology 15: 40–49.Google Scholar
  17. Noon, B. R., N. M. Ishwar, and K. Vasudevan. 2006. Efficiency of adaptive cluster and random sampling in detecting terrestrial herpetofauna in a tropical rainforest. Wildlife Society Bulletin 34: 59–68.CrossRefGoogle Scholar
  18. Petranka, J. W., C. K. Smith, and A. F. Scott. 2004. Identifying the minimal demographic unit for monitoring pond-breeding amphibians. Ecological Applications 14: 1065–78.CrossRefGoogle Scholar
  19. Philipi, T. 2005. Adaptive cluster sampling for estimation of abundances within local populations of low-abundance plants. Ecology 86: 1091–1100.CrossRefGoogle Scholar
  20. Salehi, M. M. 2003. Comparison between Hansen-Hurwitz and Horvitz Thompson estimators for adaptive cluster sampling. Environmental and Ecological Statistics 10: 115–27.CrossRefGoogle Scholar
  21. Smith, D. R., J. A. Brown, and N. C. H. Lo. 2004. Application of adaptive sampling to biological populations. p. 77–122. In W. L. Thompson (ed.) Sampling Rare or Elusive Species. Island Press, Washington, DC, USA.Google Scholar
  22. Smith, D. R., R. F. Villella, and D. P. Lemarié. 2003. Application of adaptive cluster sampling to low-density populations of freshwater mussels. Environmental and Ecological Statistics 10: 7–15.CrossRefGoogle Scholar
  23. Stone, J. S. 1992. Vernal pools in Massachusetts: aerial photographic identification, biological and physiological characteristics, and state certification criteria. M.S. Thesis. University of Massachusetts, Amherst, MA, USA.Google Scholar
  24. Thompson, S. K. 1990. Adaptive cluster sampling. Journal of the American Statistical Association 85: 1050–59.CrossRefGoogle Scholar
  25. Thompson, S. K. and G. Seber. 1996. Adaptive Sampling. John Wiley & Sons, Inc., New York, NY, USA.Google Scholar
  26. Tiner, R. W. 1990. Use of high-altitude aerial photography for inventorying forested wetlands in the United States Forest Ecology and Management 33/34: 593–604.CrossRefGoogle Scholar
  27. Weier, J. 2004. Conservation in 3D. Conservation in Practice 5: 39–41.CrossRefGoogle Scholar

Copyright information

© Society of Wetland Scientists 2008

Authors and Affiliations

  • Robin Van Meter
    • 1
  • Larissa L. Bailey
    • 2
  • Evan H. Campbell Grant
    • 2
  1. 1.Baltimore County Center for Urban Environmental Research & Education, Marine Estuarine Environmental SciencesUniveristy of MarylandBaltimoreUSA
  2. 2.USGS Patuxent Wildlife Research CenterLaurelUSA

Personalised recommendations