Photo © Erin Hauer
Human-black bear conflict has been getting increased media attention in recent years, and urbanization will likely continue to displace bears and increase conflict. In response, we want to explore the use of a native species foraging buffer as a way to reduce human-bear conflict in urban areas. Habitat enhancement efforts, like shrub planting in Canada for improved grizzly bear harvest, offer insight to the feasibility of our application, which aims to accelerate production and recovery of fruit-bearing shrubs in natural black bear habitat. By augmenting natural harvests, bears may be less prone to migrate into urban environments in search of food, thus reducing their presence and interaction with humans within the city. Even though such buffers are for the purpose of black bear stewardship, forage buffers will also benefit birds, insects and all wildlife that depend upon native shrubs as critical habitat.
This Fall, WILD and BBC are working with the support of Boulder’s Open Space and Mountain Parks (OSMP) Program to select potential forage buffer sites within Habitat Conservation Area of the Foothills ecosystem, west of the City of Boulder. With the majority of bear migration occurring into urban sections of Northwestern Boulder, this pilot project will focus on enhancing disturbed habitat in the adjacent natural areas. As the planted forage buffers mature, bear counts conducted by Brenda Lee of BBC will monitor the effect that additional harvest may have on reducing influx of bears in North Boulder.
One potential area under study is located in Sunshine Canyon, west of Mt. Sanitas. With a permit obtained from OSMP, our WILD + BBC team is in the process of conducting onsite surveys and contextual research, considering the following characteristics for suitability:
- Existing shrub species type and composition
- Native fruiting vegetation is present in sparse patches, including Boulder raspberry (Rubus deliciosus), currant (Ribes ssp.), snowberry (Symphoricarpos albus), serviceberry (Amelanchier alnifolia) and apple (Malus ssp.).
- Topographic features may provide privacy for bears and safety for pedestrians
- The area being considered for planting is an approximate 150 foot stretch along the bottom of a small valley. Relatively steep sides create a limiting boundary for pedestrian traffic in the surrounding area. A dog restriction for the nearby trail network may provide bears with a greater level of undisturbed foraging habitat.
- Clearance and accessfor maintenance
- The area is traversable and accessible with Sunshine Canyon Drive nearby. Plant material may be delivered, installed, maintained and monitored with relative ease.
- Natural depression provides source for natural water supply
- Spring runoff and seasonal storm events will provide a natural supply of water to installed vegetation. The presence of riparian vegetation indicates a high water table, which may support the shrubs during summer and in times of minimal surface water flow.
- North-south orientation of riparian corridor
- Based on principles of landscape ecology, the north-south orientation may be effective at diverting large mammals from migrating further east toward the City of Boulder. This will potentially become a holding forage spot for bears that already frequent the area, making them less apt to continue on into urban areas.
The WILD + BBC team will survey additional locations in the Foothills of North Boulder throughout the month of November. In preparation for potential springtime planting, our team will continue to research effective planting techniques for successful establishment. Gleaning from our Canadian case study, planting locally propagated and containerized young shrubs with no soil nutrient addition, which increases “the competitive ability of neighboring plants”, may be a successful model to follow. With similar landscape and vegetation types identified, the potential of this pilot project to support OSMP flood restoration and vegetation efforts is an opportunity being explored.
Erin Hauer is an intern with WILD Cities