Connectivity, networks, cores and corridors

Abstract

Ecological networks and connectivity assessment have a major role to play in supporting the adaptation and persistence of wildland areas as robust, functioning ecological units. They seek to achieve this by supporting the movement of species between discrete habitat patches. The ‘greenways’ concept developed in parallel but has a different focus that stresses the utility of linear corridors for humans. Greenways are typically defined by identifying the co-location of natural and cultural assets rather than through the dispersal of species or the location of habitat patches. When planning an ecological network it’s important to explicitly consider connectivity rather than use design-led approaches that simply ‘join the dots’ between protected areas. This process should focus on the functional and physical linkages that are already present in order to define and build upon any residual connectivity that might remain in a landscape. Understanding the relative benefits that ecological networks bring in relation to other conservation measures that might be applied in the same area is also important. A number of different tools are available that help define connectivity. Five broad approaches have been identified: spatial indices; graph theory approaches; habitat suitability models; spatially explicit population models; and individual-based models.