The shortnose sturgeon was the first fish listed as endangered with enactment of the 1973 Endangered Species Act.
A second population study in the 1990s indicated a substantial increase in the spawning population from the 1970s.
The shortnose sturgeon population in the Hudson River may now be the largest in the world. However, this assessment is based on research that is several decades old, and new studies are needed to support management and recovery actions. Newer technologies are now available, such as high-resolution side-scan sonar and acoustic telemetry, which have been successfully used to provide enhanced population estimates for other sturgeons.
This spring, academic, federal, and state research scientists embarked on a large-scale project that will provide an updated estimate for the Hudson’s shortnose sturgeon population using acoustic telemetry and side-scan sonar.
In April and May, 50 adult shortnose sturgeon were netted on the spawning grounds north of Coxsackie and surgically implanted with long-lived (10-year) acoustic transmitters. These transmitters will be detected on a river-wide array of acoustic receivers as the fish move throughout the Hudson River estuary.
In the winter, fisheries staff will use side-scan sonar to image and count individual shortnose sturgeon in overwintering areas. These estimates will be mathematically merged with the river-wide telemetry data to estimate the proportion of individual fish in the overwintering areas, and by extension, in the overall Hudson River.
More information can be found online.
Photo of shortnose sturgeon provided.