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Behney, A. C., R. O’Shaughnessy, M. W. Eichholz, and J. D. Stafford. 2014. Influence of item distribution pattern and abundance on efficiency of benthic core sampling. Wetlands. DOI 10.1007/s13157-014-0570-x

Abstract

Core sampling is a commonly used method to estimate benthic item density, but little information exists about factors influencing the accuracy and time-efficiency of this method. We simulated core sampling in a Geographic Information System framework by generating points (benthic items) and polygons (core samplers) to assess how sample size (number of core samples), core sampler size (cm2), distribution of benthic items, and item density affected the bias and precision of estimates of density, the detection probability of items, and the time-costs. When items were distributed randomly versus clumped, bias decreased and precision increased with increasing sample size and increased slightly with increasing core sampler size. Bias and precision were only affected by benthic item density at very low values (500 – 1000 items/m2). Detection probability (the probability of capturing ≥1 item in a core sample if it is available for sampling) was substantially greater when items were distributed randomly as opposed to clumped. Taking more small diameter core samples was always more time-efficient than taking fewer large diameter samples. We are unable to present a single, optimal sample size, but provide information for researchers and managers to derive optimal sample sizes dependent on their research goals and environmental conditions.

 

Current Staff

Federal Staff: 3

Masters Students: 5

Phd Students: 2

Post Docs: 0

University Staff: 1

5 Year Summary

Students graduated: 20

Scientific Publications: 42

Presentations: 108

 

Status

Published
September 2014

Unit Authors

South Dakota Cooperative Fish and Wildlife Research Unit Cooperators

  1. South Dakota Game, Fish and Parks
  2. South Dakota State University
  3. U.S. Fish and Wildlife Service
  4. U.S. Geological Survey
  5. Wildlife Management Institute