Scientific foundations for boreal conservation

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I address three challenges for conservation planning and sustainable management of Canada's boreal forests: predicting future fire regimes, predicting the future state of the forest, and developing computerized tools, or simulation models, to make these predictions over large areas and time spans of one or two centuries. ******Protected areas network designs take account of our understanding of fire regime, that is, of statistical descriptions of the number, size, and other characteristics of the fires typical of a given area. Forecasts into a future where climate and forest structure may be different than they are today is difficult, because our historical information in incomplete. In many parts of Canada, up until very recently, most small fires were not detected. This "size-biased sampling" can lead to seriously incorrect models of the effects of climate and vegetation on the outcomes of interest. Similarly, fire suppression effects may also bias our models, while at the same time changing the forest in important ways. Statistical methods can account for all these factors simultaneously, leading to unbiased models that can make reliable forecasts. ******Models of forest dynamics often use classified satellite data to describe the initial state of the forest, as being old or young, deciduous or coniferous. Obviously, the same location does not stay in the same state forever. Forests change over time through "succession" and regeneration, for example after a fire. These processes can be summarised as "state transition rules" that can be simulated by computer; unfortunately, we do not have a very clear understanding of what the rules are, and to date have relied more on expert opinion than on quantitative analysis to set parameters for computer models. It is now possible to do better, because we can now build reasonably long time series of satellite imagery for all of Canada, e.g. for the years 1990, 2000, and 2010. That is a long enough period so that it should be possible to estimate and model transition probabilities by careful comparison of the three maps. This would enable more reliable projections of future forest conditions as management and fire continue to unfold across the boreal. Doing so forms the second leg of this proposal.******The third part of this proposal involves synthesising the results of the previous two parts with the results of substantial external efforts in modelling forest songbirds, waterfowl and caribou abundances, and in protected areas planning. This synthesis will take place by continuing the development of some established modelling tools; the objective is to project how climate, forest management and conservation activities will affect the future state of the boreal forest and its wildlife into the 22nd century. Tools like this will enable us to manage with the future in mind and to achieve, as far as possible, the outcomes preferred by Canadians.