Aerial shot of fragmented forest near Geraldton
“The fragmentation of a forest may disrupt
some ecological processes and wildlife habitat, and affect its capacity
to maintain species and processes usually found in those habitats. Forest
fragments may be too small to maintain viable breeding populations of species
and excessive fragmentation can contribute to the loss of plant and animal
species that are unable to adapt to fragmented forest conditions.”
Ontario State of the Forest
Report 2001 Section 1.1.4
- Fragmentation changes habitat area and type. Reducing the amount of forest interior and increasing the amount of forest edge, favours species that prefer edge.
- Species may become trapped in fragments of forest. Many organisms e.g. salamanders, frogs, and turtles, find it difficult or impossible to disperse across inhospitable terrain. Even some bird species find it difficult to disperse across large clearcuts, and many plants, insects and other animals become increasingly confined to small ‘islands’. These islands support fewer species over time.
- Populations isolated in small patches are prone to decline due to inbreeding, and are prone to removal from the patch due to disturbances such as blow-down or changes in microclimate.
- From an ecological perspective, forest fragmentation compounds the effects of habitat loss from clearcutting: interpreting surveys of forest wildlife data as indicators of the effects of fragmentation is challenging as it is difficult to distinguish between the effects of habitat loss and fragmentation.
- There is a lack of empirical data and good fragmentation studies - the effects of forest fragmentation and connectedness of ecosystem components are difficult to assess.
