The sockeye salmon at Lake Clark National Park and Preserve undergo a truly remarkable transformation during their yearly migration where 372,000 sockeye travel from the open ocean to their freshwater spawning grounds.
Sockeye salmon are anadromous, living in the ocean but entering fresh water to spawn. While at sea, sockeye salmon sport iridescent silver flanks, a white belly, and a metallic green-blue top and are known as “bluebacks.”
When sockeye salmon return upriver to their spawning grounds, their bodies turn a striking red color and their heads become greenish. Breeding-age males develop a humped back and hooked jaws filled with visible teeth.
The folks at Lake Clark National Park and Preserve dub the transition an “extreme makeover” and remind us that even in death sockeye salmon play a crucial part in the ecosystem by decomposing and providing nutrients.
Lake Clark and its watershed provide critical spawning and rearing habitats for sockeye salmon and sustains the Bristol Bay salmon fishery which is one of the world’s largest sockeye salmon fisheries.
Lake Clark National Park and Preserve:
Extreme makeovers – they generally aren’t needed more than once every 10-20 years… But here at Lake Clark National Park and Preserve, there is one tried and true makeover extravaganza that occurs annually!
Every year there is a massive migration of sockeye salmon on their life-ending journey to return to the same waters where their life began to spawn and then die, passing on their legacy to the next generation.
During this transformative journey, sockeye will display many eye-catching looks. During the start of the return migration, they sport sleek silver-blue scales that resemble the strong ocean where they lived the past 2-3 years of their lives.
When they leave the ocean and enter freshwater, their bodies undergo many physiological changes, transforming from silver to vibrant red fashioned with green heads in preparation for spawning. Additionally, males will develop a humped back and hooked nose with elongated jaws and teeth which help them in the challenging environment of their spawning grounds.
Sockeye then take on a zombie-like appearance, dying shortly after they have spawned. Even after death, their bodies play an important role in the ecosystem by decomposing and providing nutrients.
Sockeye salmon may not be a visually stunning end-product of this extreme makeover, but they are a gift that keeps on giving to the ecosystem, and that is a beautiful outcome!
