Resampling method for applying density-dependent habitat selection theory to wildlife surveys

Area of Science:

• Ecology
• Wildlife Management
• Spatial Analysis

Background:

• Isodar theory models density-dependent habitat selection based on fitness equality across adjacent habitats.
• Current methods are limited to predefined, paired habitats, restricting broader landscape applications.

Purpose of the Study:

• To develop a flexible resampling method for constructing habitat isodars in heterogeneous landscapes without a priori habitat definitions.
• To apply this method to understand density-dependent habitat selection in raccoons and striped skunks.

Main Methods:

• A resampling technique involving random block division and sub-block abundance estimation was developed.
• Isodars were constructed by relating animal abundance to habitat feature differences between sub-blocks.
• The method was tested using wildlife survey data for raccoons and striped skunks.

Main Results:

• Habitat selection for raccoons and skunks was influenced by conspecific density and landscape composition differences.
• At low densities, species preferred habitats with high forest or anthropogenic features.
• At high densities, both species favored areas with high corn-forest edge and corn field proportions.

Conclusions:

• The developed resampling method provides a robust approach to isodar construction in complex environments.
• This flexible method is applicable to various species and incorporates multiple environmental factors.
• Isodar theory, combined with wildlife surveys, can effectively assess density-dependent habitat selection across large geographic areas.