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Animal Behaviour
Volume 72, Issue 5, November 2006, Pages 1197-1203

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doi:10.1016/j.anbehav.2006.04.005

Commentaries

Detecting oriented movement of animals

Vilis O. Nams ^,^a^,

^aDepartment of Environmental Sciences, Nova Scotia Agricultural College, Canada

Received 30 January 2006;

revised 23 February 2006;

accepted 7 April 2006.

MS. number: AS-1307.

Available online 26 September 2006.

References and further reading may be available for this article. To view references and further reading you must purchase this article.

Article Outline

Methods Unoriented movement Oriented movement
Results
Discussion Error estimates Applying the test
Appendix 1. Testing for Correlated Random Walks
Appendix 2. Animal Movement Models
References

Figure 1. Example of sampling a movement path at a larger scale of 4 step lengths.

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Figure 2. Scaling test applied to unoriented path simulations. (a) 3-Step CRW and CRW. (b) Autocorrelated turns. CWR_Diff measures how far the movement path travels compared to a CRW. Each point is the mean from 50 replicates. The nonpositive CWR_Diff values at large scales indicate random movement.

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Figure 3. Scaling test applied to directed path simulations. CWR_Diff measures how far the movement path travels compared to a CRW. The positive CWR_Diff values at large scales indicate oriented movement.

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Figure 4. Scaling test analyses of movement paths from a (a) male meadow vole and (b) female red-backed vole. The significantly positive CWR_Diff values for the meadow vole (a) indicate oriented movement.

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Animal Behaviour
Volume 72, Issue 5, November 2006, Pages 1197-1203

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