Forest Habitat Networks

In recent years, a number of forest habitat network models have been produced by Forest Research, part of the Forestry Commission.  These have used a suite of computer based evaluation tools known as BEETLE - Biological and Environmental Evaluation Tools for Landscape Ecology.

The BEETLE tool can be used to measure the functional connectivity of a landscape for a particular focal species.  A focal species is selected which is considered to be a useful representative of the wider woodland community. Often a generic focal species is used, which isn't a real species, but is an imaginary species that represents the needs of several species.

A base map is used which shows the current landscape and potential core areas of high biodiversity woodland within it.  The BEETLE approach then evaluates the permeability of the surrounding landscape for the generic focal species.  This is done by giving different land uses 'resistance weighting', which are relative to each other.  So an urban area might have a resistance weighting of 100 for most species, as they can't travel very far, or very easily through it.  In contrast, an area of semi-natural woodland might have a resistance weighting of 1 for a woodland species as they can travel through it easily.  The weightings are usually established by discussion with experts, as data rarely exists which can categorically say how far a species can travel through a particular land use.

By using this approach, areas with low resistance for a particular species can be mapped - these are the areas which that species can travel through easily and so they can be considered to be functionally connected.  Areas with poor connectivity can also be mapped and potential actions can be considered to improve connectivity and increase the extent of the network.

You can find further information on the BEETLE model and see some of the networks that have been mapped from the link on the right (and from other  links in the glossary.)