Thu, December 1, 2022
Wild Files: It’s our Nature
By Chadd Cawson Local Journalism Initiative Reporter
Sturgeon have been around for over 200 million years, working their way through the waters while dinosaurs roamed the earth. Like salmon they are an anadromous fish with 27 species worldwide and are the primary source for the delicacy caviar. White sturgeon are the largest anadromous fish in Canada and are only found in B.C. They can be easily identified from the dual rows of four to eight ganoid bony plates and despite their name are often a grey or brownish shade on their dorsal side. They have barbels which are located near the snout anterior to their mouths.
Seen swimming in many of our Columbia Valley waterways such as our upper Columbia River, and some of it’s tributaries like Arrow, Slocan, and Kootenay lake to name a few. White sturgeon is native to the Pacific coast which is why they are only found throughout B.C. but unlike their swimming buddies, Pacific salmon white sturgeon do not die upon spawning and often live to be over years 100 old.
When it comes to their own diet they feed on shellfish, crustaceans, small fish like herring and shad, insects, and gastropods but aside from humans can also make a tasty dinner for sharks, sea lions and other marine mammals. In the sturgeon world males mature faster sexually than females and are ready to spawn between the age of 12 and 18 years old. For female white sturgeon they don’t reach their full maturity to spawn until they reach between 25 and 30 years old.
Female sturgeon has many suitors and will have their eggs fertilized by many males during spawning season which happens between May and July. When a female releases her eggs, they develop an adhesive coat and are negatively buoyant upon contact with water. Dependent on the water’s temperature hatching of these eggs can take anywhere from three to 13 days. After the egg incubates, they go through the larvae and fry stage before becoming a juvenile sturgeon which at that time can become more independent with it swimming and feeding. This their last stage before maturing into full adults, when first becoming juveniles, they are typically only 10 cm long.
Quite a catch
White sturgeon have a reputation for being a challenge to catch. They can reach lengths of up to 610 cm with an average mass weighing over 500 kg. White sturgeon are considered quite rare with data showing they have seen quite a population decline over the last 30 years. Schools, or groups of white sturgeon are made up of seniors these days rounding the age of a century as they navigate the waters, one could say they are old school. When one does reel one of these remarkable ancient beauties in on the Columbia River it is intended to be recreational with an expectation to catch and release. The Committee on the Status of Endangered Wildlife in Canada (COSEWIC) has assessed White Sturgeon in B.C. as threatened with declines particularly in both the Fraser and Columbia River.
Fish tales
Chadd Cawson, Local Journalism Initiative Reporter, The Columbia Valley Pioneer
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