Abundant fishing on Kodiak Island of Alaska occurs due to several factors. One is plankton. Many of the forces of nature come together in the waters off Kodiak Island in Alaska. Why? It’s all about plankton’s needs.
Plankton need nitrate, iron and sunlight. The Pacific Current heads west from Japan, sometimes fast, sometimes slow and it slams into the panhandle of Alaska. There it splits into the Southern California current and the part going north is the Alaskan Current. The Alaska bight swings it around and directs back west. In the u-turn a gyre is set up pumping up deep cold nitrate rich water.
Storm fronts also heading west hit the Alaska Panhandle’s 14,000 foot mountains and dump enormous amounts of rain. When this rain reaches the sea, it is nitrate poor but very rich in iron. In the winter this water forms a narrow vertical wedge that is weakly stratified. The weak stratification drags what plankton that grows deep and out of the sunlight. In the Summer this vertical wedge re-forms as a shallow horizontal layer on top of the cold water in a highly stratified system where the plankton can’t get at the nitrates. During Spring and Fall life is good for plankton.
But that isn’t all. As the Alaskan Current moves west irregularities in the coastline, small islands, and the drag against the ocean floor sets up eddies. These eddies promote some mixing. And when the Alaskan current slams against Kodiak Island currents from the deep are forced up and marine life, birds, and sea lions, harbor seals become very thick and abundant. Welcome to Kodiak one of the world’s richest fisheries. The Kodiak Project documents fly fishing on the Karluk.
For Easterners you have a similar situation with a cold deep layer laden with nitrate and iron forced up by the Grand Banks into the sunlight.
While Craig and Caroline of Camai Bed and Breakfast in Anchorage have lived in Alaska for more than 34 years, this weekend is the first that Craig has visited Kodiak, Alaska. He wrote the above report.