Wetland Classification and Habitats at Risk in British Columbia

The British Columbia Ministry of Forests is developing a practical classification system for British Columbia’s wetland and riparian ecosystems. The project has identified a diversity of wetland and riparian ecosystem types, in terms of environmental profiles, regional distribution, and habitat values. Urbanization, agricultural development, hydrological modification, livestock grazing, intensive forestry, and introduction of invasive species pose the gravest threats to wetland and riparian ecosystems by outright destruction, habitat simplification, or isolation from important adjacent habitats. However, some wetland types are more sensitive to these disturbances or provide greater habitat values than others. The classification recognizes this variability in ecosystem function and can be used to identify and quantify ecosystem types of greatest concern. Given the importance of wetland and riparian ecosystems to overall ecosystem integrity, a wetland management policy that relies on the best available scientific information to protect these habitats is crucial. This classification project provides one such body of scientific knowledge that could form the foundation of a siteor region-specific policy for wetland and riparian conservation and management. Will MacKenzie Research Branch, British Columbia Ministry of Forests Bag 5000, Smithers, BC, V0J 2N0 Canada [email protected] Jennifer Shaw Ecological Consultant Box 2463, Smithers, BC, VOJ 2N0 Canada M A C K E N Z I E A N D S H AW 538 Proc. Biology and Management of Species and Habitats at Risk, Kamloops, B.C., 15–19 Feb. 1999. WETLANDS AS HABITATS AT RISK Wetland and flood ecosystems have high wildlife values particularly in arid climates where the distinction from upland ecosystems is most pronounced. These habitats are vital for wetland-dependent species, such as amphibians and water birds, and important for upland species that use wetlands and their associated riparian areas for food, water, and cover. Some features that may influence a wetland’s wildlife habitat value are water, structural diversity and cover, abundant forage, high prey densities, and unique habitat. Land management activities that affect these attributes will impact the use of the site by wildlife. WHAT IS RISK? The Concise Oxford Dictionary (1995) defines risk as a chance or possibility of danger, loss, injury, or other adverse consequences. Historically, wetlands have been exposed to high levels of risk due to poor public perception and valuation. Since early European settlement, the perception of wetlands as wastelands, available for conversion to more productive uses, has caused millions of hectares of wetlands across Canada to be drained or filled (Lands Directorate 1986). For this paper, we address risk as it applies to wetland and riparian habitats. We define risk to habitat as a function of sensitivity to disturbance, potential for exploitation, and loss of core habitat values. The 2 distinct types of habitat risk are risk of change or destruction (e.g, conversion to agricultural land) and risk of degradation or loss of value (e.g., reduce wildlife habitat capability). Habitat degradation can change ecosystem composition and structure fundamental to wildlife use without complete ecosystem destruction.