White Sturgeon, Acipenser transmontanus
White Sturgeon, Acipenser transmontanus. Fish accidentally caught from the Willamette River, West Linn, Oregon, January 2016. Length: 1.20 m (3 feet 11 inches), with fish quickly photographed and immediately returned to its native environment unharmed. Catch, photograph and identification courtesy of Luke Ovgard, Klamath Falls, Oregon.
White Sturgeon, Acipenser transmontanus. Fish accidentally caught from the Columbia River, Astoria, Oregon, March 2013. Length: 1.30 m (4 feet 3 inches), with fish quickly photographed and immediately returned to its native environment unharmed. Catch, photograph and identification courtesy of Eli (obsessiveangling.wordpress.com).
White Sturgeon, Acipenser transmontanus. Fish accidentally caught from the Columbia River, Astoria, Oregon, July 2019. Length: 1.42 m (4 feet 8 inches)with fish quickly photographed and immediately returned to its native environment unharmed. Catch, photograph and identification courtesy of Marc Eberlein, Grand Rapids, Michigan.
White Sturgeon, Acipenser transmontanus. Fish caught from the Fraser River, in New Westminster, British Columbia, Canada, November 2018. Length: 2.21 m (7 feet 3 inches), November 2018. Catch courtesy of Brad Murakami, Surrey, British Columbia, Canada with Gary Higo. Photograph courtesy of Doug Suto. Brad is heavily involved with the tagging and monitoring of the species to help with its survival.
White Sturgeon, Acipenser transmontanus. White Sturgeon, Acipenser transmontanus. Fish caught from the Fraser River, in New Westminster, British Columbia, Canada, July 2019. Length: 2.36 m (7 feet 9 inches), November 2020. Catch courtesy of Brad Murakami, Surrey, British Columbia, Canada. Photograph courtesy of Doug Suto. Brad is heavily involved with the tagging and monitoring of the species to help with its survival.
Note: In 1994 the White Sturgeon was placed on the Federal Endangered List by the United States Department of the Interiors Fish and Wildlife Service covering the known populations in Alaska, California, Idaho, Montana, Oregon, Washington and British Columbia, Canada. The fish is included in this www site to provide education to recreational anglers in case they encounter this species in the wild and can treat the catch appropriately, i.e., immediately returning to its native environment unharmed. It is also included due the availability of quality photographs taken by one of my readership who encountered the fish in the wild and asked for my help with the identification.
The White Sturgeon, Acipenser transmontanus, is a member of the Sturgeon or Acipenseridae Family, that is known in Mexico as esturión blanco. Globally, there are living seventeen species and ten species known from fossil records in the genus Acipenser, of which two are found in Mexican waters of the Pacific Ocean.
The White Sturgeon are brown or gray dorsally that transition to lighter ventrally with gray fins. They have barbels located closer to the tip of the long narrow snout than to the mouth; they have 11 to 14 predorsal scutes, 38 to 48 scutes in the lateral line, and 9 to 12 scutes in a ventrolateral line. they do not have scutes behind the anal and dorsal fins. They have 28 to 31 anal rays and 44 to 48 dorsal rays. They have two rows of four to eight ganoid bony plates on the mid-ventral line between and anus and the anal fin. They have 34 to 38 gill rakers.
The White Sturgeon is an anadromous that spends the majority of its life in oceanic waters moving to estuaries and moving far inland in fresh water for spawning. The younger females every four years and every ten or eleven years for older individuals. They are a demersal species found at depths up to 122 m (400 feet) in waters that range from 0oC (32oF) and 23oC (74oF). They reach a maximum of 6.1 m (20 feet) in length and 816 kg (1,795 lbs) in weight. The adults consume fishes; the juveniles consume chironomids, small crustaceans, insects and mollusks. Reproduction involves communal broadcast spawning on gravel or rocky substrate in moderate to fast currents with the females eggs being fertilized by many males which are sticky and attach to the substrate. They have life spans of 104 years. The White Surgeonfish is poorly studied with very limited information available about their lifestyle and behavioral patterns including specific details on age, growth, longevity, movement patterns, diet, habitat use, and reproduction.
The White Sturgeon is a resident of Mexican waters of the Pacific Ocean, but has a limited distribution being found from Todos Santos, Baja California Sur, northward along the southeast, central and northwest coasts of the Baja.
The White Sturgeon can be easily confused with the Green Sturgeon, Acipenser medirostris (barbels closer to the mouth than the tip of the snout; one large scute behind the anal fin; one large scute behind the dorsal fin; green in color).
From a conservation perspective the White Sturgeon is currently considered to be Critically Endangered. They have exceedingly long reproduction times, with females reaching sexual maturity in 30 years and males 20 years. Their long-term viability has been strongly affected by dam construction, overharvesting, and water flow alternations caused by human development. They are viewed as an excellent food fish. Their eggs are marketed as caviar and their airbladder is made into isinglass. They are heavily pursued by recreational anglers but heavily regulated with catch and release requirements of all fish. The White Sturgeon are farmed commercially in California and juveniles are sold via the aquarium trade. They have been utilized for food by Native Americans for centuries.