What Happens During Springtime in the Ocean?

Spring brings longer days, warm weather, chirping birds, budding trees, and colorful flowers. Did you know that the oceans also have their own springtime filled with activity, renewal, and even blossoms?

Every year, we notice firsthand how spring brings great change and productivity in the North Atlantic Ocean and the Norwegian Sea, which surround Kvaroy Island, where we live.

When meteorological spring begins in the Northern Hemisphere, the increasing hours of sunlight are slowly waking up primary producers in the sea. Like plants on the land, phytoplankton and plant-like organisms start to thrive.

Snow and ice melt, spring rains fall, and rivers become richer in water and move nutrients into the coastal ocean. Strong and variable spring winds also stir changes by carrying nutrients from the deep. Combining with sunlight and warmer waters, these nutrients nourish the ocean and make it fertile—first with phytoplankton and then with fish.

In the NASA image below, you can see the lighter green and milky blue areas offshore revealing the locations of blooming phytoplankton.

As everything in nature is interconnected, when the seaweed is blooming, the fish start to spawn (they lay their eggs!). You can read here more about the mutually rewarding relationship between seaweed, fish, and shellfish.

And what happens to some of the members of the salmon family during the spring?

Let’s start with Chinook salmon, also called “spring salmon,” because they spawn at this time of year. The chinook live most of their lives in the ocean, returning to where they were born in freshwater streams to spawn and give life to the next generation.

Young Atlantic salmon spend the first few years of their life living in their “birth” rivers and streams. In their second or third spring, they experience a final growing-up phase (their own “glow up”) and head off to the ocean until they become large enough to spawn. After two winters in the ocean, they migrate back to freshwater areas to reproduce.

If you want to know more about salmon behaviors and life cycles, check out our article that shares Why Salmon Love Cold Water!