By Brian Riddell
Where have the fish gone?
This question was posed last week in media across Canada, following notice by the Fraser River Panel that Fraser River summer sockeye may return at less than one-tenth of their expected abundance. It’s a seemingly simple question that is without an adequate answer. But it merits a serious response.
The “fish” in question is one group of sockeye that is produced in two lake systems of the Fraser River (Quesnel and Chilko lakes) and returns in the “summer” season. In 2009, other sockeye populations in B.C. have not suffered the apparent demise of this group, but if the 2009 return of Fraser “summer” sockeye remains at its current estimate, this will be the lowest return rate measured for Fraser River sockeye salmon in over 50 years of records.
Regrettably, resource agencies will not be able to explain this loss. Explanation would require historical records for these sockeye in several stages of their life cycle—from their parents to the return of their offspring as the next generation of adults.
To appreciate these needs and information currently available, I have summarized the life cycle of Fraser sockeye. It should be recognized though that management of Fraser River sockeye salmon is widely recognized as one of the most intensively and well managed resources in the world (see www.psc.org/).
1. Parental spawning and juvenile rearing in freshwater (18 months duration): For Quesnel and Chilko lake sockeye, the numbers of spawners and juveniles produced are amongst the best estimated for salmon in B.C., and are tabulated annually.
2. Juvenile sockeye emigrating from the Fraser River (from lake to estuary, passage likely requires one to a few weeks): There is essentially no information on the survival of small migrants (called smolts) during this stage.
3. Growth and survival in the estuary and coastal seas—for example, the Strait of Georgia (involves a few to several months, assume five months overall): Limited surveys for environmental conditions and salmon abundances within the strait. No dedicated long-term monitoring, but sampling in July 2007 indicated very low numbers of sockeye salmon (2007 is the year-to-sea for the 2009 “summer” sockeye of interest).
4. Growth and survival in the open ocean (approximately 20 months in the North Pacific): Minimal information in this stage, and information is based on indices of environmental conditions (e.g., current values relative to values perceived to be good or bad for a species). In past years, this stage would have included high-seas fishing impacts. But no surveys are currently conducted, and the situation is well monitored (see www.npafc.org/).
5. Maturation and return migration to Fraser tributaries (likely about four months), including migration to coastal waters, fisheries in B.C.’s coastal waters, up-river migration, and spawning in “home” streams: This period is intensively monitored for management of fisheries and assessment of the returning abundance. Monitoring must assess the numbers of salmon by populations of origin, the timing of the migration (see figure for 2005 Fraser sockeye return timing), and environmental conditions in the Fraser River. All of this information is essential in order to provide the desired number of spawners for each population.
What does all this mean? In the circle of these salmons’ life, information is very strong at the beginning and end of life but sadly lacking during life in marine environments (estuary, coastal seas, and open ocean).
This situation evolved for two primary reasons. First, for a long period, returns from the open ocean were variable but, on average, quite productive and provided for substantial fisheries (i.e., things were generally good and production was determined by the numbers of fish allowed to spawn). Secondly, work in the open ocean was very expensive, results were limited by the research “tools” available, and these costs were deemed unnecessary given the first point. Today, ocean productivity for Fraser sockeye is generally poorer (since the mid 1990s), is more variable, and is limiting fisheries and achievement of the desired numbers of spawners.
If the 2009 Fraser “summer” sockeye return does not improve in the next few days (see figure for 2005), then there will be demands for a fuller explanation—and rightly so. The impacts on First Nations communities and commercial fishing families will certainly be substantial. Unfortunately, this song has been heard too frequently in recent years and without adequate explanation. I know because in my past career I tried to provide those answers. To provide fuller explanation in the future, the following is necessary:
a) A dedicated research effort on early marine survival of salmon. This requires dedicated funds (in B.C., we have the people expertise to do this). This effort should start from the estuary and early marine period in the Strait of Georgia before the more difficult steps into the open ocean.
b) Replacement of the one fishery research vessel in B.C. This is scheduled by the federal government but it must be considered uncertain in these economic times. This logistic support is essential.
c) A unified front of interest groups to sustain this commitment to research and provision of answers. While many Canadians will express interest and concern in this story, the people of B.C. will feel the pain of this loss, and we need to respond together.
Given the impact of this in B.C., surely the only responsible action is for all of us to seek better answers. Certainly the causes can no longer be ignored.
Brian Riddell is the president and CEO of the Pacific Salmon Foundation.