Glossary

MCP

Minimum convex polygon.This is the smallest (convex) polygon which contains all points which the group of animals have visited. Generally it will also contain a lot of empty space that the animals never visit. It is not a particularly good measure of range, but it is frequently found in the literatureand it is easy to generate. In the example below much of the space within the MCP outline is never visited.

Etendues utilisées

An arbetrary 25x25m grid is placed on top of the area the animals use. Every grid square in which the animals have been observed is marked as part of their range.

90% contour

This is the minimum convex polygon (or in some cases a collection of several minimum convex polygons) which contains the area in which the animals spend 90% of their time. (See Wildlife Radio Tagging, pp. 175-178)

An example showing these three different range definitions
The minimum convex polygon is drawn in black,
The 90% contour is drawn in grey (except where synonymous with the MCP)
And the area used consists of the black boxes (and the shading in the box indicates the percentage of time spend in each).

For more information on different home range definitions see:

• Kenward, R. (1987) Wildlife Radio Tagging: Equipment, Field Techniques and Data Analysis. Academic Press, London.