Biologists are performing surgery on scores of endangered fish in New York's Hudson River.
Shortnose sturgeon and Atlantic sturgeon are being caught in nets, anesthetized and subjected to small incisions so transmitters can be inserted into their body cavities.
The idea is to track the fishes' movements and see how they are affected by the construction of a huge bridge spanning the river. In addition, it's hoped the information can boost the species' long-term prospects.
On Wednesday a biologist on a rocking boat performed one such operation, cutting and stitching in just minutes before releasing the fish.
If all goes well, its movements will be tracked for months by underwater receivers, relaying its travels and feeding habits.
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