Monitoring Abundance Of Juvenile Atlantic Sturgeon - The Fisherman

Monitoring Abundance Of Juvenile Atlantic Sturgeon

Since 2003, fish biologists in DEC’s Hudson and Delaware Marine Fisheries unit have been studying the population, life cycle, and habitats of the endangered Atlantic sturgeon to manage and conserve this signature species.

Atlantic sturgeon spawned in the Hudson spend one to six years in the river before they migrate to the ocean. Annual counting and tagging of these young sturgeon help determine how the relative abundance is changing over time in response to management actions such as the coast-wide fishing moratorium established in 1998. By analyzing several years’ worth of catch data, biologists can determine population trends in the Hudson River stock. Is it stable, increasing, or decreasing?

Juvenile Atlantic sturgeon monitoring takes place in late February through early May in Haverstraw Bay, an overwintering area for these young fish. Research shows the combination of soft, river-bottom sediments and deeper water (more than 20-feet) is preferred habitat for juvenile Atlantic sturgeon.

Fisheries staff use anchored gill nets to catch sturgeon. They are weighed, measured and examined for previous tags. A small sample is taken from each fish for genetic and age analysis. Fish are tagged under the dorsal fin with a Passive Integrated Transponder or PIT tag. This tag is similar to a microchip put in pets and is about the size of a grain of rice.

Since the start of the program in 2004, standardized monitoring indicates the numbers of juvenile Hudson River Atlantic sturgeon are increasing. The average catch rate in recent years is two times higher than that observed during the start of the survey suggesting the Hudson River stock may be recovering in response to the coast-wide fishing moratorium enacted 23 years ago. Additional years of monitoring will help establish recovery targets for the species as a whole.