Joe Wheaton - Beaver: Restoration liaison between riparian and upland systems
Beaver (Castor canedensis), well known for their dam-building ecosystem engineering activities and potential as a nuisance species, are increasingly being used as a restoration agent and conservation tool to restore dynamism in streams and create better habitat for a variety of threatened biota. Beaver don’t build dams everywhere, but where they can, they are a potentially cheap alternative to restoring degraded stream habitats. Beaver will harvest dam building materials and forage up to 150 meters away from their ponds, and this activity extends their zone of influence from just within streams and riparian areas up into uplands. Their harvesting activities mimic that of a rotational crop farmer, where instead of decimating and clear-cutting an area, they selectively forage and work an area hard for a number of years, before resting it and moving elsewhere. The vegetative response (particularly of aspen forests) to this disturbance typically results in a more diverse and vigorous regrowth. Examples of restoring streams with beaver will be shared that highlight how beaver can reconnect incised channels with their former floodplains, expand riparian areas into uplands, and invoke population level responses in salmon. Beyond that, a model that predict the capacity of the landscape to support dam-building activity by beavers will be presented that helps build realistic expectations about where beaver may or may not be appropriate restoration agents. These examples will be brought together with some suggestions of how upland and riparian restoration efforts can feed off each other with the help of beaver.