Fish & Habitats– White Sturgeon (Acipenser transmontanus) in British Columbia

Small whole sturgeon
Big fish

Frequently Asked Questions on the status
and consequnces of listing White Sturgeon

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The white sturgeon is a unique freshwater fish species that plays a significant role in British Columbia's cultural and social heritage, as well as our economy. The white sturgeon (Acipenser transmontanus) belongs to the sturgeon family Acipenseridae. Not only is it the largest sturgeon species in North America, it is also the largest freshwater fish species in North America. The only other sturgeon species found in British Columbia waters is the green sturgeon (Acipenser medirostris Ayres). However, very little is known about this species except that it tends to be found under more marine and coastal conditions.


White Sturgeon are found in 3 major drainages on the west coast of North America including the Sacramento (in California), Columbia (in British Columbia, Idaho and Washington) and Fraser systems. In British Columbia, spawning populations of white sturgeon occur in three rivers: the Fraser/Nechako, Columbia and Kootenay. White sturgeon have also been observed in the mouth of the Cowichan and Somass rivers on Vancouver Island. However, it is likely that these fish represent stray fish from the mainland systems, possibly the Columbia River in Washington, rather than separate spawning populations.



It is difficult to mistake white sturgeon for other species (except close sturgeon relatives). These large fish have been known to grow up to 6 metres long (the length of a small school bus) and over 600 kg. The overall body form is long and cylindrical, usually ranging in colour from greenish grey on the dorsal (back) side to light grey or white on the ventral (belly) side.

Sturgeon body.

The body is covered with large armour-like scutes (bony plates) rather than scales like other fishes.

The nose or rostrum of white sturgeon is flattened. On the underside of the rostrum just in front of the mouth are four barbels or fleshy whisker-like projections that are used as sensory organs to detect food since the water is often murky at the bottom of the river.

Sturgeon mouth.

Most of the skeleton is made up largely of cartilage rather than bone, and the overall appearance is quite prehistoric, which makes sense since sturgeon have remained virtually unchanged since they first appeared in the fossil record 175 million years ago.

Shortnose sturgeon

Some variation in colour and morphology (body shape) has been observed in white sturgeon in B.C. For example, snout length differs markedly in the Fraser - short nosed and long-nosed fish are both common.

Longnose sturgeon.

Life History

One trait that makes the white sturgeon so unusual is its incredibly long lifespan. Some individuals are over 100 years old - these individuals were around even before British Columbia became part of Canada. Given their long life, they tend to grow slowly and are not ready to spawn until the females are over 18 years of age and males are at least 14 years of age. Unlike many salmon species that spawn once and die, white sturgeon are capable of spawning many times throughout their life.

White sturgeon depend on a number of environmental cues in the spring to spawn - these include water temperature, day length, strength of water current and riverbed material. Adult sturgeon do not build nests but rather the male and female release sperm and eggs together in the water current - called broadcast spawning. A female may release between 100,000 to 3 million eggs but only a small number may actually get fertilized. Once they are fertilized, the eggs become sticky and attach to the river bottom as soon as they come into contact with it. The young embryos mature into larvae in 8-15 days and then spend another 20-30 days nestled in the river bed until they metamorphose into free- swimming young sturgeon.


Tracking studies indicate that sturgeon generally don't move more than a few km during the summer feeding season. However,before spawning or when traveling to over-wintering locations, sturgeon can migrate over 100 km. Adult fish tend to occur in deeper, faster waters of large river mainstems, where they spend most of their time on or near the bottom of the riverbed. Juveniles prefer slow moving sloughs and backwaters. Spawning habitat is usually in turbulent fast water, but locations can range from shallow murky side channels with pebbly and sandy bottoms to deeper, less murky main channels with larger boulders and cobble.



The body shape and mouth structure of white sturgeon is ideally suited to bottom feeding. Although sturgeon have poor eyesight, they use their highly sensitive barbels to locate prey. Rather than using teeth, sturgeon have a extendible mouth which they can use like a vacuum cleaner to suck up prey.

Small sturgeon feed on chironomids, as well insect larvae, molluscs and other small invertebrates. Larger sturgeon switch to a fish-based diet although chironomids can still make up a significant part of the diet. White sturgeon in the Fraser are known to follow sockeye runs and also feed on eulachon, sculpins and stickleback.

Many of the threats to white sturgeon are specific to the river system in which they live. In general, these threats include over-fishing, hydro-electric dams and associated flow regulation, water diversions and dyking for flood control and irrigation, introduced species including predators and competitors, reduced water quality associated with various land-use practices (e.g. forestry) and loss of habitat from dredging, gravel mining and other industries.


In 1990, the white sturgeon was classified by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC) as a Species of Special Concern, but this national designation is overdue for review. The BC Conservation Data Centre (CDC) has subsequently reviewed the status of white sturgeon in British Columbia and has provincially listed it as imperiled (the second highest 'at-risk' rating), putting it on BC's red list. Three populations (Nechako, upper Columbia and Kootenay) were given the highest possible ranking of critically imperiled. The Kootenay population, which is a trans-boundary population shared with Idaho and Montana, has been listed as endangered under the US Endangered Species Act (1994).

Since 1995 we have added greatly to our understanding of white sturgeon biology and habitat requirements. Unfortunately, these studies have confirmed that the Nechako, upper Columbia and Kootenay populations are declining drastically as a result of recruitment failure. This means that these populations are not replacing themselves, either due to unsuccessful spawning or poor survival of the young. Without conservation action these populations will likely go extinct.


Recovery Planning

The development of a recovery plan for the Kootenay sturgeon was led by the US Fish and Wildlife Service with the assistance of both federal and provincial biologists from British Columbia. The plan is being implemented on both sides of the border. Currently, the provincial Fisheries Program has initiated recovery planning processes for both the Nechako and upper Columbia populations. These planning processes will involve representatives from all levels of government, First Nations and stakeholders with the overall objective of restoring healthy, self–sustaining populations to each watershed.

The purpose of recovery plans is to stabilize the remaining population(s) and prevent further declines and extinction, and ultimately, to rebuild the population(s) to a healthy, self–sustaining state. To date, the provincial white sturgeon recovery plans have been made up of 2 components: (1) a long–term goal to identify and address the reason(s) for decline and restore the population to a self–sustaining state; and, (2) an interim goal to preserve the remaining gene pool and prevent further loss to the population through conservation fish culture.

Provincial Programs

Increasingly, fish species are being identified at being at some risk of extinction. Conservation and recovery programs must be developed in a strategic and focused manner because significant cost and effort is often required to protect and recover threatened or endangered species.

In British Columbia, the Provincial Fisheries Program is responsible of the management and conservation of anadromous (sea–run) trout and freshwater fish species. Furthermore, under the Accord for the Protection of Species at Risk (signed in 1995), the province committed to undertake a variety of actions to identify, protect and develop recovery plans for species at risk. The federal Species at Risk Act (SARA) would make many of the commitments made under the Accord a legal requirement.

To address concerns regarding the status of white sturgeon in British Columbia, the Fisheries Program has established a number of river–specific programs. These programs are designed to increase our knowledge of white sturgeon biology and habitat requirements in order to better protect this unique species. These programs include:

Fraser River White Sturgeon Program

Nechako River White Sturgeon Program

Columbia White Sturgeon Program

Other information:

Provincial Species at Risk brochure