Beaver Hills Initiative

The Landscape: Managing Sustainability - What's It Take?

Natural communities are not static, nor do they oscillate around a particular ecological state, always returning to a 'normal' community type (Primack 2002). Instead, natural communities are dynamic: the ecosystem shifts to a new state in response to time or disturbance. The habitat and species we see in an area now will change as the site succeeds to new vegetation communities over time or responds to disturbance (e.g., windthrow, fire). In deciding that we want to maintain natural areas with some level of development, we must accept this characteristic and accommodate it in our management approach.

A dynamic ecosystem is regulated by three interrelated components: ecosystem structure (physical features of habitat) and composition (biological communities) are tied to function (Noss 1990). Simply put, these are the ingredients that determine the direction of the processes that regulate the ecosystem. For example, a wetland supports vegetation and wildlife distinct from more upland habitat. Starting as a sedge-bounded pond, such a site might evolve over time to an open pond surrounded by dense cattails and then to one with cattails and dense willow along its edge. Chemistry and seasonal fluctuation of water are functional aspects that regulate change in this system, but that change is restricted by the wetland's physical features (water, soil types) and biological communities (wetland species).

The interdependency of ecosystem structure, composition and function are critical to effective management. To sustain natural areas, we need to ensure that ecosystem structure and composition are maintained — i.e., that the ecosystem continues to function effectively. If ecological functions are intact, ecosystem structure and composition are perpetuated. For this reason, we need to design conservation efforts that focus on natural ecosystem processes, rather than the ecological community itself. Using our wetland example, we want to ensure that the wetland persists, not just cattails. So what are these ecological processes, and how do we ensure that they are effectively managed?

Island biogeography theory as described by MacArthur and Wilson (1967) and subsequent authors is now widely used in designing protected areas networks. This includes examples similar to the Beaver Hills, where a network of protected lands lies within a more developed landscape (e.g., Banff and Jasper National Parks and the adjacent foothills). The theory explains how core protected areas, the islands surrounded by development, can effectively maintain ecological functions that act within and between them.

Eleven aspects of effective protected area network design have been identified based on this theory and are listed in Table 1. Qualitative examples of management effectiveness along a continuum of good to poor are also provided in the table.

Conservation Network Design

The Beaver Hills, in their current state, comprise a network of protected areas surrounded by buffer lands with various levels of human development. Outside the moraine is a second buffer area - a matrix of agricultural, industrial and urban land use. On the continuum scale in Table 1, the Beaver Hills would score mainly on the Most Effective management side.

The proposed regional management approach for the Beaver Hills would address the last two aspects of effective protected area network design: regional management of a protected area network and buffered human use around the protected areas. Buffering human use effectively means limiting the extent of fragmentation and human activity immediately adjacent protected areas. Ideally, land use in the buffer lands surrounding the various protected areas across the Beaver Hills would concentrate development in the outer buffer lands and be less intensive near the protected areas.