Gulls feeding on salmon eggs and carcasses, Juneau, Alaska. Chum Salmon (aka “Dog Salmon”) and Pink Salmon (aka “Humpies”) spawning in Sheep Creek estuary. CLICK THE PHOTO BELOW TO SEE VIDEO: 10 seconds into video, a chum salmon with red and purple stripes thrashes into shallows. Past this chum salmon out in the channel, see the humped backs of pink salmon in spawning frenzy.
Pinks and Chums are the only two species of salmon whose fry (newly hatched young) migrate immediately back to saltwater. They become “smolt”: their bodies and metabolism change so they can live in saltwater. The young of the other 3 species (Chinook, Coho, and Sockeye) stay in streams and lakes for 1 or more years before they go out to sea.
Once in the ocean, their life histories diverge. Pink salmon spend only 1 year feeding in saltwater, migrating back into the streams as 2-year-old adults, the smallest of the salmon at 2.2 kg (4.8 lbs.). Chum Salmon remain in the ocean for 2-4 years, so return as 3 to 5-year-olds. Their longer life of feeding and growing results in weights of 4.4 to 10.0 kg (9.7 to 22.0 lbs.)
The high protein-high fat salmon and their eggs are super-foods for predators like gulls, shorebirds, bears, and humans. As they die, the nutrients from their bodies feed aquatic and terrestrial plants and invertebrates from crab to insects in the Coastal Temperate Rainforest. These are critical habitats and migratory passages that require protection from pollutants, destruction, and blockage.