Spatial and temporal scaling of population density and animal movement

A power law approach
Ecoscience
Author(s): 
James A. Schaefer and Shane P. Mahoney

Many ecological patterns are sensitive to spatial and temporal scale, but no general protocol has emerged for dealing with scale-dependence. The authors suggest that power laws, regularly used in the study of body size, can be applied to many such features. The authors used these techniques to describe two scale-sensitive aspects of caribou (Rangifer tarandus): population densities of North American herds when measured at varying spatial extents, and speeds of radiotracked individuals when observed at varying temporal resolutions.

Habitat selection at multiple scales

Ecoscience
Author(s): 
Stephen J. Mayor, David C. Schneider, James A. Schaefer, and Shane P. Mahoney

Habitat selection is the disproportionate use of available conditions and resources, and involves responses in space and time to perceived risks and rewards. It frequently depends on the scale of measurement, often in non-linear ways that preclude simple extrapolation across scales. More critically, animals often select different habitat components at different scales, and species vary in their scales of selection. Although multi-scaled research on habitat selection has proliferated, synthesis of this work has been impeded by imprecise terminology and arbitrarily defined analytical scales.