Simulated effects of forest management options on timber and caribou habitat in the Northern Columbia Mountains

Introduction Mountain caribou, an ecotype of woodland caribou (Rangifer tarandus caribou), are a primary focus for forest management in the Columbia Mountains Forest District. Models have been developed based on multivariate linear regression of telemetry data to predict caribou habitat by associating forest cover and physiographic variables at various spatial scales and seasons (Apps et al. 1998, 1999). Using a GIS, these models produce maps that can be used to classify the landscape into good, moderate, poor and non caribou habitat with relative certainty. Understanding the long-term consequences of management actions on caribou habitat is critical to develop forest management policy that minimizes the risk to caribou populations while achieving other objectives such as timber extraction. Applying the above caribou habitat models in other spatial contexts (e.g. Golden Timber Supply Area) or temporal contexts (e.g. in a projected future forest condition) increases the uncertainty of model predictions; however these models represent the current best knowledge on caribou habitat affiliations in the area, and could be critical to assessing the impact of different management scenarios on caribou habitat. We applied the Columbia Mountains Landscape Model (Daust et al.2000) to (i) assess the feasibility of implementing the caribou habitat models in the SELES landscape modelling environment; and (ii) assess the impacts of three difference management scenarios on caribou habitat as predicted by the habitat models. In the following text, we describe the results of this simulation experiment. Model descriptions can be found in (Daust et al.2000). Below, methods describe management scenarios, and list the outputs monitored. Results compare differences among the outputs. The discussion interprets results and places them in context. Methods We simulate five different forest management scenarios: (a) NoMgmt: a no-management control (i.e. no timber harvesting in the landbase). (b) NoCHG: a no Caribou management zone control (i.e. no special management rules for caribou, but otherwise the same as the TSR scenario (c)). (c) TSR: timber harvesting according to the Timber Supply Review (TSR) rules B.C. Ministry of Forests. 1998a; 1998b). (d) MAC1: timber harvesting according to the Ministers Advisory Committee (MAC) rules in Revelstoke TSA and the TFLS, with TRS rules applied in Golden TSA. Harvest patch size is taken from the Forest Practices Code, with adjacency constraints. (e) MAC2: Same as MAC1 except that harvest patch size is taken from the patch size distribution of the biodiversity guidebook, with no adjacency constraints. 3 All harvest scenarios include (i) …