Each summer as the migratory striped bass spawning run tapers off, juvenile bass hatch from eggs in the upper reaches of the Hudson River Estuary and begin a downriver journey of growth and survival.
These tiny fish quickly reach several inches in length over a few months, then spend time in the lower estuary and coastal ocean until they are large enough to join the coastal migratory stock.
How has New York kept track of these juvenile striped bass and other estuarine fish? With the help of dozens of technicians and biologists in the Department of Environmental Conservation’s Hudson River Fisheries unit, who have pulled in a beach seine over 8,300 times over the past 45 years.
In 1979 DEC began monitoring annually for young-of-year (YOY) striped bass in the Haverstraw and Tappan Zee regions of the Hudson River. The survey utilizes a 200-foot small mesh net deployed in a horseshoe shape by boat to collect juvenile striped bass and other juvenile estuarine species like white perch, Atlantic menhaden, and Atlantic silversides among other brackish species at 13 stations throughout the sample region.
Before returning the fish to water, they are identified and counted, and a subset is measured. Since 1979 DEC staff have measured over 300,000 fish during striped bass beach seining. Because it spans such a long time-series, this YOY survey has generated an invaluable fishery-independent dataset for the Hudson River Estuary.
YOY survey data are used to generate a juvenile abundance index (JAI) for Hudson River striped bass, calculated as the geometric mean catch per haul.
The Atlantic States Marine Fisheries Commission, responsible for managing striped bass and other migratory Atlantic coast species, uses this index along with data inputs from other surveys to guide regulations that hopes to ensure a robust striped bass population for years to come.
In addition to target species data, the numerous fish counts, length measurements and water quality data may be used to detect changes in fish communities and nursery habitat conditions in the sampling region. The growing dataset can continue to inform management decisions about striped bass and Hudson River fish species in the future.
(Since 1985, a 500 foot haul seine and an electrofishing boat are used from April through June to catch spawning striped bass for a Spawning Stock Survey.)., Length, weight, and sex information is recorded and scale samples for aging are collected from the fish before being tagged and returned to the river.
Read more stories about the Hudson River.
Illustration; Mid-October striped bass sampling day, DEC technicians pull in the 200-ft seine at a Nyack beach.
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