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Sturgeon Tagging


 
Fishing for sturgeon in the Hudson River? That’s been banned for two decades. Except these aren’t fishermen looking for a catch to sell, these are biologists trying to fit tracking devices to an Atlantic, or Short-Nosed Sturgeon and throw it back in. They’ve checked about 20 nets today with no luck and this is the last.
Four miles north of the heavy construction to replace the old Tappan Zee Bridge, scientists are electronically tagging 120 sturgeon to see if the vibrations from pile-drivers are hurting the fish or changing their habits.
JUSTIN KREBS, FISH ECOLOGIST: At the construction site we have an array of approximately 30 acoustic receivers that allow us to continuously monitor the presence and movement and locations of fish within the construction site.
There are two reasons; one is to look at how they’re responding to the underwater noise from pile-driving and responding to construction activities in general. The other one is to learn about their ecology in the river, um, which areas of the river they’re using most frequently…where they might be feeding. Uh, how the adults are moving when they come into the river to spawn.
Sturgeon were once plentiful in the Hudson but massive overfishing killed the fish and the industry and a 40 year moratorium was imposed in 1996.
FRANCES DUNWELL, NEW YORK STATE DEPARTMENT OF ENVIRONMENTAL CONSERVATION: The adult sturgeons are not being killed anymore and those stocks are rebuilding but the biology is similar to a person. They don’t mature to spawn until they’re 15, 16, 17, 18 years…the females, maybe 15 before they are able to reproduce. So you have that long waiting period after you protect a fish before it’s able to rebuild the stocks.
Some will even get their stomachs pumped to analyze their contents. This one escaped that ignominy. Just a few stitches and a half an hour of being prodded and poked…back in the water it went. Next subject please.

Source: nytimes

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