Estimating landscape resistance to dispersal

Tabitha Graves, Richard B. Chandler, J. Andrew Royle, Paul Beier, Katherine C. Kendall

Research output: Contribution to journalArticle

33 Citations (Scopus)

Abstract

Dispersal is an inherently spatial process that can be affected by habitat conditions in sites encountered by dispersers. Understanding landscape resistance to dispersal is important in connectivity studies and reserve design, but most existing methods use resistance functions with cost parameters that are subjectively chosen by the investigator. We develop an analytic approach allowing for direct estimation of resistance parameters that folds least cost path methods typically used in simulation approaches into a formal statistical model of dispersal distributions. The core of our model is a frequency distribution of dispersal distances expressed as least cost distance rather than Euclidean distance, and which includes terms for feature-specific costs to dispersal and sex (or other traits) of the disperser. The model requires only origin and settlement locations for multiple individuals, such as might be obtained from mark-recapture studies or parentage analyses, and maps of the relevant habitat features. To evaluate whether the model can estimate parameters correctly, we fit our model to data from simulated dispersers in three kinds of landscapes (in which resistance of environmental variables was categorical, continuous with a patchy configuration, or continuous in a trend pattern). We found maximum likelihood estimators of resistance and individual trait parameters to be approximately unbiased with moderate sample sizes. We applied the model to a small grizzly bear dataset to demonstrate how this approach could be used when the primary interest is in the prediction of costs and found that estimates were consistent with expectations based on bear ecology. Our method has important practical applications for testing hypotheses about dispersal ecology and can be used to inform connectivity planning efforts, via the resistance estimates and confidence intervals, which can be used to create a data-driven resistance surface.

Original languageEnglish (US)
Pages (from-to)1201-1211
Number of pages11
JournalLandscape Ecology
Volume29
Issue number7
DOIs
StatePublished - 2014

Fingerprint

cost
costs
connectivity
habitat
ecology
reserve design
parentage
hypothesis testing
frequency distribution
confidence interval
fold
confidence
parameter
simulation
planning
prediction
trend
method
distribution

Keywords

  • Animal movement
  • Connectivity
  • Corridor
  • Cost distance
  • Dispersal
  • Landscape permeability
  • Least cost path
  • Movement

ASJC Scopus subject areas

  • Nature and Landscape Conservation
  • Ecology
  • Geography, Planning and Development

Cite this

Graves, T., Chandler, R. B., Royle, J. A., Beier, P., & Kendall, K. C. (2014). Estimating landscape resistance to dispersal. Landscape Ecology, 29(7), 1201-1211. https://doi.org/10.1007/s10980-014-0056-5

Estimating landscape resistance to dispersal. / Graves, Tabitha; Chandler, Richard B.; Royle, J. Andrew; Beier, Paul; Kendall, Katherine C.

In: Landscape Ecology, Vol. 29, No. 7, 2014, p. 1201-1211.

Research output: Contribution to journalArticle

Graves, T, Chandler, RB, Royle, JA, Beier, P & Kendall, KC 2014, 'Estimating landscape resistance to dispersal', Landscape Ecology, vol. 29, no. 7, pp. 1201-1211. https://doi.org/10.1007/s10980-014-0056-5
Graves, Tabitha ; Chandler, Richard B. ; Royle, J. Andrew ; Beier, Paul ; Kendall, Katherine C. / Estimating landscape resistance to dispersal. In: Landscape Ecology. 2014 ; Vol. 29, No. 7. pp. 1201-1211.
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