Robert Hallock, Ph.D. Biologist - Northern Idaho Field Office, USF&WS: "The Kootenai River population of white sturgeon has been isolated by a natural barrier at Bonnington Falls for about 10,000 years. They occupy Kootenai Lake in British Columbia, and then they spawn in the Kootenai River near Bonners Ferry, Idaho. Some fish move on up into Montana but most of them use the Idaho portion of the system.
We’ve identified them as a unique population. That’s why the listing is specific to that population of fish. They’re smaller than most white sturgeon - the biggest fish that’s been documented is about 200 lbs. whereas the biggest white sturgeon is over 1300 lbs. They have some unique genetic characteristics which would support that they have been isolated above the Falls for a long period of time. There’s been very little recruitment for the last 20 years."
Within a half-century, several dams were constructed on the Columbia River ranging in distance from 35 miles to 75 miles apart. The first is Bonneville Dam, constructed in 1938 near Portland, Oregon. The series of dams above Bonneville Dam were built by the federal government in the mid-1930s through the mid-1970s. Those dams isolated at least 13 populations of white sturgeon in the middle and upper Columbia River into eastern Washington, up into Canada, and also in the Snake River into Idaho. Reproduction of landlocked white sturgeon in those areas is failing. Moving further up river near the headwaters are white sturgeon populations that have become endangered, or have been extirpated.
Below Bonneville Dam the free-flowing Columbia River reaches 145 miles to the Pacific Ocean. That section of the river has remained in its natural state with open access to the ocean. As a result, the white sturgeon population is quite healthy, and supports a regulated sport and commercial fishery.
White sturgeon are an ancestral species. They predate the dinosaurs, and have remained relatively unchanged for millions of years. They are inherently an anadromous species meaning they migrate from the sea into rivers to spawn. There are isolated populations of white sturgeon that were landlocked during the construction of dams in the mid to early 1900s.
White sturgeon are the largest of the eight North American species of sturgeons. They are long lived, and sexually late maturing. They do not have scales, rather their bodies are armored with several lengthwise rows of bony plates called scutes. Their body is torpedo shaped with a sloping head. They have four barbels that dangle just in front of the mouth. The barbels serve as sensory organs for locating food in the benthos, or bottom sediment. Their upper body color ranges from gray to pale olive, and their underside is white. They can weigh over 1500 lbs, measure 20 ft. long, and live to be 100 years old.
Serge Doroshov, PhD with the Department of Animal Science at the University of California, Davis is one of the world’s leading experts on
sturgeon and sturgeon culture. He introduced the Russian technique of Ceasarian section on females for extracting sturgeon eggs for artificial propogation.
Dr. Doroshov: "Sturgeon is a very valuable fish for fish farming. It grows relatively fast and it has very high flesh quality and it also produce a caviar. The farming here basically started in 1985 with the white sturgeon, and today farmers produce about one million pounds a year. Primarily this fish goes to the restaurant sales, but they also trying to diversify the product, and they produce some smoked sturgeon and caviar as well. So it is success story.
Sierra AquaFarms, Elverta, California
During the late 1800s, commercial fishermen targeted white sturgeon, taking several million pounds a year for several years.
White sturgeon were prized for their smoked flesh, roe for caviar, and swim bladders for the making of isinglass.
Large numbers of sexually mature white sturgeons were harvested to the point of significantly depleting populations throughout their historic range.
After the turn of the century, state and federal resource agencies began closer management of white sturgeon populations in an effort to restore depleted stocks to sustainable levels. A 4 ft. size restriction was initially put into place, and that population slowly rebuilt.
In 1950, an upper size limit of 6 feet was adopted; a move considered by many to be one of the most important moves in the history of sturgeon fishery management. The white sturgeon slot limit extended to all fisheries including the treaty Indian fishery, the commercial fishery, and the sport fishery. Within 20 years, the results were evident in the abundance of white sturgeon in rivers where dams and other man-made obstacles don't impede natural reproduction of the species.
The largest white sturgeon on record was taken in 1898 on the Snake River in Idaho. It weighed a little over 1503 lbs. (682 kg).
The United States Postal Service honored the white sturgeon on the face of a postal stamp as the largest freshwater fish in America which was included in their 2006 Commemorative Edition, "Wonders of America - Land Of Superlatives".
©2006 United States Postal Service
The USPS created an artist's rendition from the original image it licensed from Earthwave Society.
In addition to his aquacultural research, Dr. Doroshov collaborates with state and federal agencies in the reproductive biology of wild stocks of sturgeons, and assists with restocking programs.
DOROSHOV: I think the future of wild sturgeon stock would depend on whether we will be able to protect the remaining few spawning grounds for different species. Therefore those species will be allowed to reproduce naturally, and if they will be protected, they will still exist. Some species are now in a situation where they cannot reproduce naturally because of in part of the dam and hydro-construction, and changes in the flow of the river. Those species would require some more complex and more expensive problem to maintain their population by artificial reproduction because genetic breeding plan should followed, not only artificial reproduction techniques.
The one-hour documentary, Sturgeon: Ancient Survivors of the Deep, is available at our DVD Gallery. Click the link in the right margin.