POTENTIAL CONFLICTS BETWEEN TIMBER SUPPLY AND HABITAT PROTECTION IN THE BOREAL MIXEDWOOD OF ALBERTA, CANADA - A SIMULATION STUDY

The boreal mixedwood forests of northern Alberta, Canada, are now bein g brought under management for pulpwood production. A simulation model ling exercise was undertaken to evaluate the sustainability of planned logging operations, and to explore their potential effects on wildlif e habitat. Model inputs include the species composition and age struct ure of the forest, annual coniferous and deciduous volume requirements , and descriptions of natural stand mortality and regeneration, operat ional constraints, and silvicultural policies. Simple habitat suitabil ity submodels simulate the effect of changes in forest composition on wildlife species. The model was used to explore the implications of a variety of management policies over a 73 000 km(2) forest estate in th e mixedwood region. Simulations of current harvesting plans indicate t hat projected levels of harvesting may be sustainable, but many wildli fe species will lose substantial amounts of preferred habitat. Harvest ing can probably not be sustained without converting most of the regio n's characteristic mixed-species stands to production of single specie s. Alternative plans which maintain unharvested reserve areas can prot ect habitat (areas of mixed stands in particular) for some wildlife sp ecies, but may entail significant increases in operating costs or redu ctions in harvest levels. Furthermore, the reserve strategies we consi dered are able to maintain only between 12% and 41% of high-quality ha bitat for species dependent upon older stands of commercially valuable timber. Because species have different habitat requirements, increase d protection for some species may exacerbate habitat losses for others .