A new study shows how the Wuikinuxv Nation shares sockeye with neighbouring grizzly bears.John E Marriott
For years, the Wuikinuxv First Nation on Rivers Inlet, B.C., has been one point on an ecological triangle with sockeye salmon and grizzly bears. Now, a detailed study of that three-way relationship has demonstrated how a resource under pressure can be managed to maximize benefits to the entire system.
The results suggest that Indigenous salmon fishing in the area can be handled in a way that provides for both the community’s and the bears’ needs without depleting fish stocks.
The study has wider implications for the region, which witnessed the full-scale collapse of a once-thriving commercial sockeye fishery 25 years ago. Using an approach known as ecosystem-based management, it shows that a complex ecological relationship can be quantified with enough precision to enable practical decision-making about a resource. It also adds some crucial evidence to discussions about how the remaining salmon population can be maintained over the long term as the First Nation heads into treaty talks with federal officials.
“We set out to look at tradeoffs between people and bears,” said Megan Adams, a postdoctoral researcher at the University of British Columbia who conducted the work in conjunction with the Wuikinuxv community. “What we found is a point where the benefits from the fish that the community catches are balanced by the benefits that bears gain from the fish that are left in the ecosystem.”
Seven years ago, Dr. Adams began a collaboration with the community to study grizzly bears in the region.Andy Wright/The Globe and Mail
However, the analysis also found that – at least for now – such a balance could not be reached with a commercial fishery in the mix.
“This is an excellent case study for an issue that will probably arise more and more,” said Joseph Bennett, a biologist at Carleton University in Ottawa who was not involved in the work but whose lab specializes in decisions related to conservation and biodiversity.
“Fisheries stocks have collapsed in other places as well,” Dr. Bennett said. “As those stocks recover, often with sustainable Indigenous management, I suspect that there will be a clamouring for reopening of commercial non-Indigenous fisheries.”
The study took advantage of the unique geography of the region, where Pacific sockeye salmon that migrate up Rivers Inlet all pass through a single channel only five kilometres long before entering a large, freshwater lake fed by nine separate river systems. This has allowed members of Wuikinuxv First Nation, which is at the head of the inlet about 400 kilometres northwest of Vancouver, to participate in the monitoring of the salmon population there and measure the effect of fishing for food, social and ceremonial purposes. For the past three years, the community opted not to catch its full requirement of sockeye because of low numbers of fish.
A narrow passage
Nine rivers and a watershed that covers 3,500 square
kilometres all drain through the single channel that is the
location of the Wuikinuxv First Nation. The unique geop-
graphy of the region has allowed for a detailed analysis
that links the number of salmon moving through the
channel to the bear population of the watershed and
to the broader health of the ecosystem.
Detail
Watershed
B.C.
Alta.
Protected
Vancouver
Pacific
Ocean
UNITED
STATES
Wuikinuxv Village
Owikeno Lake
Rivers Inlet
Walbran
Island
BRITISH COLUMBIA
0
6
KM
THE GLOBE AND MAIL, SOURCE: TILEZEN;
OPENSTREETMAP CONTRIBUTORS
A narrow passage
Nine rivers and a watershed that covers 3,500 square kilometres all
drain through the single channel that is the location of the Wuikinuxv
First Nation. The unique geography of the region has allowed for a
detailed analysis that links the number of salmon moving through
the channel to the bear population of the watershed and to the
broader health of the ecosystem.
Detail
Watershed
B.C.
Alta.
Protected
Vancouver
Pacific
Ocean
UNITED
STATES
Wuikinuxv Village
Owikeno Lake
Rivers Inlet
Walbran
Island
BRITISH COLUMBIA
0
6
KM
THE GLOBE AND MAIL, SOURCE: TILEZEN;
OPENSTREETMAP CONTRIBUTORS
A narrow passage
Nine rivers and a watershed that covers 3,500 square kilometres all drain through the
single channel that is the location of the Wuikinuxv First Nation. The unique geography
of the region has allowed for a detailed analysis that links the number of salmon moving
through the channel to the bear population of the watershed and to the broader health
of the ecosystem.
Detail
Watershed
B.C.
Alta.
Protected
Vancouver
Pacific
Ocean
UNITED
STATES
Wuikinuxv Village
Owikeno Lake
Rivers Inlet
Walbran
Island
BRITISH COLUMBIA
0
6
KM
THE GLOBE AND MAIL, SOURCE: TILEZEN; OPENSTREETMAP CONTRIBUTORS
The area once had one of the most abundant commercial sockeye fisheries, with millions of salmon returning each year to spawn. However, stocks plummeted in the mid-1990s, which previous studies have attributed to overfishing and environmental factors. In 1999, the number of returning sockeye dropped below 10,000. By then commercial fishing was suspended, but the broader effect on the environment and the community was just becoming apparent. That year, the Wuikinuxv village was inundated by emaciated grizzlies, which depend on the sockeye as a food source, and 15 bears had to be destroyed as a public-safety measure.
“That’s not something that we want to see,” said Danielle Shaw, chief counsellor of the Wuikinuxv First Nation, which supported the study. “If anything, our community is always trying to find ways in which we can coexist more peacefully and make sure that our bear population is healthy.”
Data suggest the sockeye population of Rivers Inlet has settled into a new equilibrium of about 200,000 fish – 94 per cent fewer than before the collapse.Grant Callegari/Hakai Magazine
Seven years ago, Dr. Adams began a collaboration with the community to study grizzly bears in the region while working toward her PhD at the University of Victoria. Her research includes gathering hair that bears leave behind as they brush past barbed wire collectors set up in the forest. The hairs are analyzed for isotopes that can reveal the extent to which salmon is part of the bears’ yearly diet. The information is related to the health of the ecosystem as a whole, because if the bears are consuming more fish, that is because more salmon are available overall, and this helps support other species as well.
In the new study, published on Tuesday in the journal Marine and Coastal Fisheries: Dynamics, Management, and Ecosystem Science, Dr. Adams combined her bear hair data with sockeye population numbers to show the intertwined dependence of the Indigenous community and the bears on the salmon.
She found that if the community catches 10 per cent fewer fish than the estimated maximum that can be taken for a sustainable population, the bears can gain a corresponding 10 per cent increase in population density. That level represents the optimal trade-off, although the authors caution that their numbers are subject to uncertainties in future fish productivity and other variables.
The data suggest the sockeye population of Rivers Inlet has settled into a new equilibrium of about 200,000 fish – 94 per cent fewer than before the collapse.
Brendan Connors, a research scientist with Fisheries and Oceans Canada who collaborated on the study, said the results should help empower the community as it seeks to protect a resource that is central to its cultural fabric, particularly if the sockeye population continues to rebuild and commercial fishing is considered.
“It’s imperative that there’s great care placed in when, how and to what extent fisheries occur,” Dr. Connors said.
Sarah MacDonald/Supplied