Know your fish: The Sockeye Lifecycle
The 2019 fishing season was the sixth largest run of all time (Bristol Bay Fishing Report, 2019). The preseason forecast called for a run of 40.2 million sockeye with an actual return of 56.3 million, that is 33% higher than predicted, can you envision what an additional 16 million salmon look like? With such impressive numbers on a large scale, it is easy to overlook the equally impressive life cycle that each individual sockeye has in common.
The name Sockeye comes from a rough translation of the name Suk-Kegh, originating from the Pacific Northwest’s native coast Salish language dating back as far as 6,000 years ago, meaning “red fish.” Sockeye are also known as “blueback salmon” because during their time spent in the ocean they sport a metallic green-blue back which contrasts against their white bellies. And, of course, they are prized for their succulent, bright orange meat. As sockeye return to their spawning grounds, they go through an incredible transformation resulting in a vivid red bodies with bright green heads, hence the name “red salmon.” Males develop a humped back and hooked jaw that differentiates them from the females. This is the final stage in their life cycle.
Now, let’s take a look at the journey that got us here:
- Sockeye return to spawn in June and July into freshwater river systems and lakes.
- Females dig small cavities in the sand and gravel called “redds” with their tails over several days, into which they deposit 2,000-5,000 eggs. Males then swim over these eggs and fertilize them. Both males and females die within a few weeks of spawning.
- The eggs hatch in the winter and the “alevins” remain in the gravel, feeding from their yolk sacks until they grow into “fry” and move into rearing areas. Fry will spend one to three years feeding on zooplankton in freshwater lakes. If there are no lakes, the juveniles will travel to the ocean immediately after coming out of the gravel
- By now the young fish have grown into “smolts,” each weighing a few ounces; they are ready to make their springtime journey into the ocean.
- As soon as the fish enter salt water, they begin to experience rapid growth. Sockeye will spend up to five years in the ocean, travelling thousands of miles swimming in the counterclockwise current of the Gulf of Alaska. An adult sockeye can range between 18 and 31 inches and a weight of 4 to 15 pounds.
As mature salmon begin to return to their river systems in June and July, they are ready to be harvested. Tribal and First Nation groups depend on salmon returns not only for subsistence, but many ceremonial aspects of their lives as well. The Alaskan fishing industry also depends on strong salmon runs which can be seen in the thousands of jobs and millions of dollars contributed to the economies of both Canada and the United States. The looming Pebble mine is a direct threat to indigenous people and all Bristol Bay fisheries by potentially having a catastrophic effect on salmon populations, which would directly impact the lives of thousands of people.
Making their way upstream is the final step after their arduous journey, and as the sockeye lay their eggs, another life cycle begins. The mature sockeye die and their bodies provide nutrients that feed the developing salmon, insects, and aquatic plant life. An entire ecosystem, including bears and eagles are supported by spawning salmon…how can we not protect them?