Spatial Aggregation, Precision, and Power in Surveys of Freshwater Mussel Populations

@article{Downing1992SpatialAP,
  title={Spatial Aggregation, Precision, and Power in Surveys of Freshwater Mussel Populations},
  author={John A. Downing and William L. Downing},
  journal={Canadian Journal of Fisheries and Aquatic Sciences},
  year={1992},
  volume={49},
  pages={985-991}
}
  • J. DowningW. L. Downing
  • Published 1 May 1992
  • Environmental Science
  • Canadian Journal of Fisheries and Aquatic Sciences
We studied aggregation in 76 populations of freshwater mussels from relatively homogeneous surroundings in a wide range of habitats. Chi-square tests for spatial aggregation found only 53% of mussel populations significantly (p   1. The number of replicate samples () required to estimate mussel abundance with a given level of precision (D = SE/m) is approximately m−0.5D−2. Sampling mussels with large quadrats requires between 5 and 25 samples for 20% precision. Sampling designs to determine… 

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References

SHOWING 1-10 OF 34 REFERENCES

Sampling Larval Fish Populations: Choice of Sample Number and Size

A model is developed, based on published data, to predict the variance in larval fish abundance among replicate samples, which was found to be general across environments, life history stages, and species.

Precision of the mean and the design of benthos sampling programmes: caution advised

Using data from the freshwater benthic literature, Downing (1979, 1980a) calculated a regression equation to predict sample variance from sampler size and population density and concludes that massive savings may be achieved by using sample units of small surface area.

Aggregation, Transformation, and the Design of Benthos Sampling Programs

The fourth-root transformation stabilized the variance in all macrobenthos samples while either the commonly used square root or logarithmic transformations did not.

Sampling variance and the design of quantitative surveys of the marine benthos

It is shown that the sample variance of marine benthos increases with the sample mean (m) and can be predicted with a high degree of precision from the equation: s2=1.641 m1.219 (r2=0.86, n=3015).

Variability of Density Estimates and the Optimization of Sampling Programs for Stream Benthos

It is suggested that none of the commonly used transformations will stabilize the variance at all the densities encountered, and information about sampler size improves the prediction of the logarithm of sampling variance, which increases with an increase in mean density and decreases with a increase in the size of the sampler.

Role of a Unionid Clam Population in the Calcium Budget of a Small Arctic Lake

  • R. Green
  • Environmental Science, Geography
  • 1980
Growth rate and morphometric parameters were estimated for the Anodonta grandis population in Shell Lake, N.W.T. (68°N), based on sampling during the summer of 1972, and independent estimates of calcium used for shell growth, and of calcium released by death of individuals and subsequent shell dissolution, approximate 50% per year.

Ecological and Genetic Studies on Dreissena polymorpha (Pallas): a New Mollusc in the Great Lakes

A high level of genotypic diversity indicated that the Dreissena polymorpha population was founded from a substantial number of individuals and did not undergo a bottleneck subsequent to founding.

The Spatial Response of Chironomid Larvae to the Predatory Leech Nephelopsis obscura

The spatial heterogeneity of the chironomids decreased when they were released from predation, perhaps to minimize competition between the larvae, and the plasticity of spatial behavior of the Chironomid larvae probably contributes to maintaining this dynamic balance.

Distribution and Morphological Variation of Lampsilis radiata (Pelecypoda, Unionidae) in Some Central Canadian Lakes: A Multivariate Statistical Approach

A canonical correlation analysis on morphological and environmental variables for 70 specimens of L. radiata yielded two highly significant canonical variates which related components of environmental variation to components of morphological variation.

Spatial interrelationships of bivalves and nonbivalve benthos in a small reservoir in New Brunswick, Canada

Quantitative sampling of macrobenthos in Morice Lake, New Brunswick, showed that the numerical abundance of chironomid larvae and other nonbivalve detritivore species was significantly increased in