The Young of the Year Index has always fascinated me. This is also known as the YOY Index or the Juvenile Striped Bass Index.
The index is the result of an annual survey done by the Maryland DNR to determine the spawning success of Striped Bass in the Chesapeake Bay area.
This survey has been done every year since 1954. Maryland DNR biologists survey 22 sites in the four major spawning systems ─ the Choptank, Nanticoke, and Potomac rivers, as well as the Upper Bay of the Chesapeake.
The crews visit each survey site three times during the summer, collecting fish samples with two sweeps of a 100-foot beach seine.
To calculate the indices, biologists count and then average the juvenile fish caught in the samples. They then create the Young of Year Index.
When compared to the YOY from prior years, it helps to give an indication of the success or failure of that Spring’s spawning season in the Chesapeake Bay.