Transitioning between seasons can often push your senses to work overtime. This is especially true in summer and autumn in the Atnarko River corridor, where the river comes alive with Chinook, chum, pink, sockeye, and coho salmon runs. The smell of a river containing spawned-out fish is unforgettable, and one I have grown fond of. Carcasses swirl in eddies before sinking to the river bed or getting snagged on log jams. Thorough log jam inspections are routinely pursued by predators and scavengers, including grizzly bears — our study species. I often feel my stomach growl when I observe grizzlies feast on fatty flesh of salmon. Knowing this nutrient-dense food is critical for bear reproductive success and fitness during hibernation, to hear their loud crunching and gnawing on fish ensues deep satisfaction, but also concern. Early observations suggest salmon availability was below recent averages on the Atnarko River this year.
Despite poor salmon returns, crowds of curious people also descend on the Atnarko, many of them tourists hoping to watch bears feed. People travel to the corridor, located in Tweedsmuir Provincial Park, Nuxalk Territory, from all over the world to bear witness to the feeding frenzy. How this non-consumptive ecotourism activity might affect the interaction between bears and salmon is unknown in this system.
In collaboration with BC Parks and the Nuxalk Nation, the Raincoast Applied Conservation Science Lab has launched a multi-year research project to understand if ecotourism has any effects on bear presence, numbers, and behaviour. Accounting for the availability of salmon and berries, we are measuring how human presence and intensity might influence the detection of bears at sites, as well as their behaviour. For example, we are measuring foraging rates (i.e., salmon captured per unit of time), capture efficiency (i.e., salmon captures per attempt), and key behaviours, like vigilance. In addition to hours of observation, we utilize technology. We deploy remote cameras and non-invasive hair snagging stations to genetically tag bears to understand how site occupancy and abundance might vary with spatial and temporal variation in human activity.
Waiting for bears to appear on the river requires patience. In some stretches of the corridor, we often wait many hours before an opportunity to collect behavioural data presents itself. With my Research Associates Kelly Milton (Nuxalk Nation Fisheries and Wildlife Lab) and Andrew Sheriff (University of Victoria), we use a tree stand at our most upstream site – a ‘reference area’ where no human activity occurs on the river. Providing an unobstructed view of some fishing locations, the stand allows us to collect data safely. When a bear arrives on site, we employ focal sampling, where we record, and later code, key behaviours such as vigilance and foraging. At all our sites, focal samples will allow us to estimate the proportion of time bears spend selecting key behaviours.
Bear research is also about bear safety, especially given that we have largely lived ‘off-the-grid’ in the park. We take bear safety lessons learned from the Nuxalk Fisheries and Wildlife Lab and communities in Bella Coola Valley, and apply them to our daily living. An electrified fence surrounds our clean research camp, ensuring that our interactions with bears have been few, distant, and neutral. Co-existing with bears peacefully is a vital component to doing field research in their homes.
We anticipate more research seasons living among bears and dedicated to reading their cues. Long-term conservation outcomes can in some cases be predicted early by subtle behavioural changes that, if detected, provide managers with an opportunity to intervene before population-level changes occur. This research will seek to inform management as it relates to human activity in the park, and empirically advance our understanding of the behavioural ecology of grizzly bears.