Decline in and delayed salmon on the Skeena River

Observation by Kristen Davis

Skeena River salmon are an important part of the socio-economic and ecological network in the Pacific Northwest region, from the headwaters to the open ocean. The Skeena watershed is home to 60,000 people and over 80 per cent of Skeena residents interact with wild salmon (Skeenawild.org). The abundance of wild stocks in the region is currently at risk of nearing its critical threshold: in danger of extinction (Price, 2014). This could have a major impact on the health and wellbeing of the people in the entire region.

My family and I have harvested salmon on our traditional Lax Skiik (Gitxsan clan) fishing grounds (coordinates: https://www.google.com/maps/@54.9047852,-128.3807693,14.41z) for generations. In recent years, we have observed the salmon arriving at our territory along the Skeena River later than normal and in fewer numbers. Price et. al (2014) claims that the total number of wild sockeye (Oncorhynchus nerka) returning to the Skeena River have decreased by 69% in comparison to historical stocks. He and his team have also observed a decline in genetic diversity (-70%), which puts the sockeye at a disadvantage when it comes to adapting to the environment. This lack of resilience in the population: “the capacity of a system to withstand and adapt to change to remain within the critical thresholds of its current regime” (Holling, 1973), and the decrease in stock, leaves the wild Skeena River sockeye population with a lack of capacity to adapting to any uncertain major disturbance event, and at risk of collapse.

The issues of lower numbers and lack of biodiversity of the salmon population is a result of many different factors at many different temporal and spatial scales. External abiotic events such as climate change has a major impact on salmon ecosystems. Climate models have shown a warming trend in rivers in the Pacific Northwest (Wu, 2012). Streamflow and temperature are important variables contributing to the quality of salmon habitat, and the magnitude and variability of streamflow and temperature affects the timing of salmon’s timing of migration (Wu et al., 2012). Price (2014) speculates that at warmer temperatures, the salmon that do return at a later time in the season, may actually be better adapted to those warmer temperatures. Additionally, the social and economic benefits that Skeena River salmon have provided for the communities in the region have resulted in the over-harvesting within the commercial, recreational and traditional food fisheries along the river system (Price, 2014). The cumulative effects of poor habitat quality, lower diversity and over harvesting places the salmon population at extreme risk of collapse from a disturbance event. Price (2014) suggests the need to end the commercial fisheries and move toward local harvests upriver, and managing those fisheries at the population level, in order for the salmon population to rebuild and renew, and avoid approaching its critical threshold. Ignoring the economic growth of the region and reducing the harvest will restore the resilience of the salmon population (Farley & Voinov, 2016).