How to Determine the Age of a Rockfish
- 1). Obtain a fresh rockfish carcass.
- 2). Place the dead rockfish on a hard plastic or wooden chopping board. Position the tail away from you.
- 3). Place your thumb and forefinger into each of the rockfish's eye sockets.
- 4). Place a sharp knife with a blade in the middle of the head of the rockfish, one eye diameter behind its eyes.
- 5). Position the blade at a 30-degree angle, slanting away from you.
- 6). Slice backwards towards the tail of the fish and down into its head. Carefully apply pressure to cut through the skull. Make an incision approximately one head length long.
- 7). Lift and remove the top section of the skull, which you will have cut through.
- 8). Check to see if the white brain is visible.
- 9). Observe where the spinal cord connects to the base of the brain.
- 10
Take hold of the nose and tail section of the rockfish and press these two ends carefully together. This action typically severs the spinal cord at the base of the brain, and pushes both the brain and otoliths toward you. - 11
Gently tear the otoliths loose and remove them. - 12
Rinse the otoliths under running water. - 13
Hold an otolith carefully but firmly with a pair of tweezers, and place it into the flame from an alcohol lamp. - 14
Watch the otolith turn a yellow-brown color. Remove the otolith once it has turned gray. - 15
Break the otolith carefully in half and place one half under a microscope. - 16
Look for the alternate dark and light bands. - 17
Count the dark bands. The number of bands coincides with the age of the rockfish in years.
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