Active Fans and Grizzly Bears: Balancing Risks for Wilderness … · 2009. 5. 29. · Active Fans...

Active Fans and Grizzly Bears:Balancing Risks for

Wilderness Campers

Dave WilfordMatt Sakals

Deb Wellwood

Overview

• Blending of geoscience and wildlife biology

• Campsites - geomorphically and bear-human interaction safe

• Looking for bare sediment…• Risk assessment• Most people are happy…

Risk Assessment – Flood Fan• 154 km2 and Melton 0.16• Major peaks in June, July, August –

snowmelt• Diurnal variation – 8pm – 6am• Snowmelt peaks augmented by 2 to 4

days of rain• Predictable• “Policy” of no camping on Bullion Fan

Site Features on Flood Fans

• Elevated sites with escape access• Sites >50 m from forest edge• Access to cooking water• Some cover from main valley wind

Risk Assessment –Colluvial Fans

• 1.2 – 7.4 km2 and Melton 1.4 – 0.6• Difficult to differentiate processes• Events occur after 2 to 4 days of

rain – with or without snowmelt• Weather history and forecasts are

available

Site Features – Colluvial Fans

• Exposed to valley wind and blowing silt• 6 to 8 degree slopes• Coarse or compact sediment• Lack of fresh water• Gentle slopes are on distal areas, as are

escape routes, but…• These areas are close to bear routes

Conclusions

• Camping on fans in the Slims River Valley is possible with limited hydrogeomorphic and bear risk

• Key site and weather features• “No camping on Bullion Creek”• But, with the wind, campers may seek

refuge in the forest…amongst bears