A new study, the “Ecology of conflict: Marine food supply affects human-wildlife interactions on land” published in the journal Scientific Reports, finds that in areas with spawning salmon and grizzly bears, bear-human conflict is higher in years when salmon abundance is low. This finding has important implications for wildlife management.
Scientists from Raincoast Conservation Foundation, Simon Fraser University, University of Victoria, and the Hakai Institute analyzed 35 years of data on “conflict-killed” grizzlies in BC—animals killed because of a perceived threat to human safety or property. The researchers found that levels of conflict varied substantially from year to year.
“We took an ecological approach to investigate what might underlie these yearly patterns,” says Chris Darimont, Hakai-Raincoast professor at UVic and science director at Raincoast. The results were striking: the natural availability of food- especially spawning salmon-played the biggest role in explaining yearly conflict patterns. In salmon-eating populations of grizzlies, yearly conflict levels increased by an average of 20% for each 50% decrease in salmon availability.
The researchers also found that across BC, 82% of conflict events occurred while bears were fattening up for hibernation—when bears need food the most. This timing suggests a link between food availability and conflict in all bear populations across the province, with or without access to salmon. Although attacks on humans were exceedingly rare, most (50 of 62; 81%) occurred in the pre-hibernation period when bears eat the most, further suggesting a link to food availability. Whereas it has previously been asserted that sport hunting and government-sanctioned kills of conflict bears reduce overall conflict and thus protect people in subsequent years, this study found otherwise.
“What we found challenges a common assumption in wildlife management—that killing bears is necessary to reduce conflict. Instead, we found that the killing of bears through conflict removals or trophy hunts had no measurable effect on overall conflict patterns,” says lead author Kyle Artelle, Raincoast biologist and Hakai PhD scholar at Simon Fraser University. “We ought to understand how ecology drives conflict before pulling the trigger on lethal approaches to conflict mitigation,” says Artelle.
Although this study suggests the need for rethinking common approaches to conflict management, encouraging examples of effective approaches already exist. Jason Moody is the Fisheries and Wildlife Coordinator for the Nuxalk Nation Stewardship Office of Bella Coola, an area with a history of bear-human conflict. His team addresses the full context of conflict: prioritizing protection of salmon runs (in part for bears), working with residents towards conflict-proofing neighbourhoods, putting up electric fencing, and replacing foods lost to bears such as salmon prepared outdoors. Results have been impressive. “We have never resorted to killing a bear, yet we never see our bears “re-offend”. As we have done for millennia, we manage ourselves, not our bears, and have had a 100% success rate,” says Moody.
Bears, and other wildlife, are not considered in salmon management. For more information click here.
Additional background notes
The conflict patterns explored in this study have real-world implications on BC’s coast. For example, Jennifer Walkus, a bear researcher and resident of Wuikinuxv First Nation and village (formerly “Rivers Inlet”), has witnessed the associations between bears and humans first-hand. Walkus notes, “In 1999, we witnessed an unprecedented decline in salmon. We have lived with these bears for millennia without problems, but following this collapse we watched conflict levels go through the roof. The loss of salmon to our river not only took food off our
Walkus notes, “In 1999, we witnessed an unprecedented decline in salmon. We have lived with these bears for millennia without problems, but following this collapse we watched conflict levels go through the roof. The loss of salmon to our river not only took food off our tables, but resulted in bears in our backyards.”
An important local implication of this study is a current and substantial mismatch between ecology and management. Bear managers, who work for the province, have no authority over salmon management, and salmon managers at the federal government have virtually no considerations for bears in salmon management decisions. “The association between salmon and bear-human conflict proves that we need to implement policies that consider wider ecosystem interactions in fisheries management,” says John Reynolds, the Tom Buell BC Leadership Chair in Salmon Conservation and Management at Simon Fraser University. The Fisheries and Oceans Canada “Wild Salmon Policy”, which dictates that fisheries management should consider ecosystem needs, promises to do just that, though it has yet to be implemented on the ground.