Sturgeon are present in Alaskan waters. These ancient fish, known for their distinctive appearance, inhabit various marine and freshwater environments throughout the state. Their presence contributes to Alaska’s rich aquatic biodiversity, making them a notable part of the region’s aquatic life.
Sturgeon Species in Alaskan Waters
Alaskan waters are home to two species of sturgeon: the green sturgeon (Acipenser medirostris) and the white sturgeon (Acipenser transmontanus). Green sturgeon are widely distributed along the Pacific coast, ranging from Mexico northward to the Bering Sea. White sturgeon also inhabit the Eastern Pacific, extending their range from Monterey, California, up to the Gulf of Alaska and potentially the Aleutian Islands. Alaska represents the northernmost extent of both species’ ranges in North America.
Where Alaskan Sturgeon Reside
Sturgeon in Alaska primarily inhabit nearshore marine waters, estuaries, and major river systems. Green sturgeon are found along the western coast of North America, including southeastern Alaska, and range as far north as the Bering Sea. They often concentrate in bays and estuaries, particularly in deep areas with soft bottoms. While green sturgeon are highly migratory in coastal waters, their spawning is generally limited to specific rivers further south in Oregon and California.
White sturgeon are also present in southeastern Alaska, though their distribution center is closer to the Columbia River. They reside in large rivers and their associated estuaries but can also be found in coastal waters. While some white sturgeon populations are landlocked elsewhere, those in Alaska are anadromous, migrating between freshwater and marine environments. Sightings in the Yukon River suggest their expansive migratory patterns can lead them further inland.
Distinguishing Features of Alaskan Sturgeon
Sturgeon are recognized by their unique, prehistoric appearance, characterized by a cartilaginous skeleton and rows of bony plates called scutes instead of scales. Green sturgeon have an olive-green coloration and a long, narrow, shovel-like snout. They possess whisker-like sensory organs called barbels on the underside of their snout, which aid in detecting food on the bottom. Green sturgeon can reach lengths of up to 7 feet and weigh around 350 pounds, living up to 70 years.
White sturgeon are larger, with historical records indicating lengths up to 20 feet, though 10-12 feet is now considered large. Their coloring ranges from gray to brownish on the dorsal side, with paler ventral sides. Similar to green sturgeon, they have barbels anterior to the mouth and distinct rows of scutes along their bodies. White sturgeon are among the longest-lived freshwater fish in North America, with some individuals reaching 100 years of age.
Conservation Status and Management
The conservation status of sturgeon species in Alaskan waters varies, reflecting broader population trends across their range. The Southern Distinct Population Segment (DPS) of green sturgeon is listed as threatened under the Endangered Species Act (ESA). The Northern DPS of green sturgeon is considered a species of concern, requiring monitoring. Threats to green sturgeon include migration barriers, habitat degradation, and climate change impacts like warm water events and ocean acidification.
Management efforts for sturgeon often involve strict regulations due to their late maturity and infrequent spawning. While specific management plans for sturgeon within Alaska are limited, broader efforts across their range focus on habitat protection and preventing overharvest. Conservation organizations have advocated for listing and critical habitat designation to protect these vulnerable populations. The long lifespan of sturgeon makes their populations slow to recover, highlighting the need for ongoing conservation measures.