The Spatial Scale of a Species’ Response to the Landscape Context Depends on which Biological Response You Measure
Purpose of Review
Our ability to detect effects of the landscape context on wildlife often depends on the spatial scale at which environmental variables are measured. Theory suggests that the scale at which the species most strongly responds to this context—its scale of effect—should depend on the type of biological response. This is hypothesized to occur because the temporal scale regulating the response is linked to the spatial scale at which the species interacts with its environment; i.e. the scale of effect should be larger for responses influenced by forces acting over longer time periods. Here I test the prediction that the scale of effect increases in the order: fecundity < abundance < occurrence < genetic diversity, using a quantitative review of studies that empirically estimated scales of effect.
The scale of effect of a given environmental variable depended on the type of response in 70% of the 145 cases identified in this review. However, scales of effect did not increase in the predicted order. This is likely, at least in part, because some studies did not include a wide enough range of scales in their analyses to accurately estimate the scales of effect.
Future research is needed to test this prediction using study designs that allow for accurate estimation of scales of effect. Nevertheless, my results have implications for wildlife research and landscape management, suggesting that we cannot assume that a species responds to its landscape context at only one scale.
KeywordsLandscape size Meta-analysis Multi-scale Scale of response Spatial extent Temporal scale
I thank the members of the Carleton University Geomatics and Landscape Ecology (GLEL) Friday Discussion Group, the section editor, and two anonymous reviewers for their comments on earlier versions of this manuscript.
Compliance with Ethical Standards
Conflict of Interest
I have no conflicts of interest to declare.
Human and Animal Rights and Informed Consent
This article does not contain any studies involving human subjects. This article references one study with non-human animal subjects performed by A.E.M. . This work was done in accordance with the guidelines of the Canadian Council on Animal Care, and was approved by the Carleton University Animal Care Committee.
Papers of particular interest, published recently, have been highlighted as: • Of importance •• Of major importance
- 7.•• Miguet P, Jackson HB, Jackson ND, Martin AE, Fahrig L. What determines the spatial extent of landscape effects on species? Landsc Ecol. 2016;31:1177–94. A comprehensive review of hypothesized drivers of scales of effect and the support (or lack thereof) for each hypothesis. This is the first paper to formalize the prediction tested in my quantitative review. CrossRefGoogle Scholar
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