A Good Year for Pinks

We took a stroll down to Puntledge Park in Courtenay the other day, to see the salmon in action. All seemed quiet at first, then with a sudden splash we spotted a salmon, swimming up through the riffles of the stream. The salmon spawn is a beautiful thing, and reminder of the natural cycles of life and death that we are all a part of. Along river’s edge, we found a freshly deceased male pink salmon, and admired the colours and markings of the fish up close. The pink salmon (Oncorhynchus gorbuscha) is the smallest and most abundant of the five species of Pacific salmon. Pinks weigh between 1.0-3.3 kg, and are 45-55 cm long. A key identification feature is the tail, which has tiny scales that have no silver, and distinctively large oval spots.

During the ocean phase pinks are silver with spotted backs. In their freshwater phase males have yellowish-gray sides, and are darker on the back. They have a hooked lower jaw, and a distinctive hump in front of the dorsal fin, which earns them the nickname “humpies.” Females are more olive-green, and both males and females are dirty white on the lower half.

Pinks have a short, two-year lifecycle, peaking on odd numbered years in southern waters (here), and on even-numbered years in northern waters. Pink runs have been exceptionally good in our area in 2009, which is likely a reflection of the intensive conservation work that has been ongoing for the many years. In Courtenay, the Tsolum River had 44, 260 pinks this year, and the Puntledge had at least 41, 000. The Quinsam, in Campbell River, had a record-breaking return of around 800, 000 pinks.

Like all Pacific salmon, the pink is anadromous, which means that it is born in freshwater, journeys to the ocean to grow and mature, then returns to its birth stream to reproduce and die. The salmon lifecycle is one of the most miraculous, and mysterious, phenomenons of the Pacific coast.

The lifecycle begins in the fall when the female lays thousands of eggs in a nest, or “redd” that has been excavated in the gravel of a streambed. The male’s sperm or milt fertilizes the eggs, and soon afterwards, the adults die.

Over the winter months embryos develop within the eggs and eyes begin to appear. When the embryo reaches a certain size, the eggshell is dissolved, and an alevin emerges. The tiny alevins have a head and tail, and a yolk sac on the underside of the belly from which they receive all of the nourishment they need.

After a time, the yolk sac is absorbed, and the alevin becomes a fry. The fry swims up from the gravelly nest to the stream surface, where it gulps air to inflate its swim bladder. Next is the critical stage of imprinting, when the fry memorizes all the stimuli surrounding it, including specific odours, and other unique features of its birth stream, that will enable it to return to the same spot to spawn in a few years (pretty impressive!)

Pink fry soon migrate to the ocean. The estuary, or river mouth, where fresh and salt water mix, is a place of abundant food and nutrients essential to the salmon’s survival. The young salmon face many hazards in reaching the estuary, such as starvation, numerous predators such as birds, animals and other fish, and disease.

The young salmon in the estuary, known as a smolt, eventually ventures out into the open ocean, where it will spend the next few years feeding and growing. Prior to spawning, the salmon stop feeding, and exist on stored fat reserves. When conditions are right, they journey up the home stream to their birthplace. Salmon face many perils as they travel up-river, having to swim against the current, and overcome obstacles such as fallen trees, waterfalls, and predators.

While some salmon may only go a short distance, others battle hundreds of kilometres upstream to spawn. Spawning females who have made it to their birthplace seek out a suitable nesting site. The male follows suit, defending a territory against other males. The female deposits the eggs, and thus the lifecycle begins again.

Salmon are a fundamental part of the food chain, and many creatures depend on them for survival. Even after the scavengers have moved in, the salmon carcasses and bones continue to return nutrients to the stream and the forest floor.
The flesh of pink salmon is pale, and has a delicate flavour. Many consider it to be inferior to other salmon, but pinks are none-the-less a very important fish commercially, and still sought after by many sports fishermen.

The survival of Pacific salmon faces many challenges, largely as a consequence of human activity past and present. Countless individuals and groups work tirelessly on salmon enhancement and stream restoration projects. This stewardship must continue if Pacific salmon species are to survive.

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