Lower Black River Lake Sturgeon Monitoring (2010)
Lake sturgeon (Acipenser fulvescens), is currently listed as a threatened species in New York. Restoration activities for this species began in 1993 with supplemental stocking in St. Lawrence River tributaries. Since then, supplemental stocking, spawning bed enhancement and research has expanded to a broader area, including the Eastern Basin of Lake Ontario and Central New York.
Spawning was previously documented in the lower Black River (Dexter, Jefferson Co.) in 2005. Historically, this river had a well known fishery for sturgeon which is documented by photos of large fish from the 1940's in several collections. Pollution and overfishing depleted sturgeon numbers to where only remnant stocks remained in Lake Ontario. Sightings of sturgeon by anglers in the Dexter area since 1995 prompted the initial exploratory survey in 2005. Monitoring has continued annually since then whenever river flows were amenable to sampling.
The lower Black River was sampled from April 4-30, 2010, to monitor lake sturgeon use during the spawning period. Monofilament gill nets (10 inch stretch) were fished at a single location near the mouth of the river to intercept fish on their way to the spawning bed. A total of nine net nights (~216 hrs) of fishing effort were expended. The Black River was at record low water discharge in 2010 which allowed nets to "fish" effectively with little bias from fouling or drift.
A total of 25 new lake sturgeon were captured during the survey. Data collected included, length, weight, and reproductive stage. Fin samples were collected for future genetic analysis, and all fish were tagged with either a FloyTag or Passive Integrated Transponder (PIT) tag.
Nineteen PIT tags were deployed. These tags are permanent and will allow researchers long into the future to track individual fish with respect to spawning site fidelity, migration patterns, and growth characteristics. Of particular interest in 2010 was the recapture of fish #1764 which was originally tagged at this location in 2006, and captured again in 2009.
