Last spring during our Trolling For Troops "tournament", the veteran I had on my boat landed this 37" laker,
We kept the fish to have it mounted, but after the event we found out that the taxidermist that donated his service only did replicas, I ended up getting the fish from him and asked the biologist here in Gray if they could age it and they agreed, so I brought it to them and they took the odoliths out and aged them.
I'm no biologist by any means, so if I get something wrong here, please correct me, or if you can add something, please do, I think this is cool stuff.
The odoliths are little slivers of calcium right behind a fishes brain that they hear with, basically their ear drum, and just like a tree, they grow a ring every year, the odoliths in this fish where about 1/3 the size of the fingernail on my pinkie and about the same thickness. The way they age them is to slice them, polish the faces that were cut and count the rings under a microscope. This picture is one of the odoliths from the fish we caught after it has been sliced and polished under a microscope, hopefully you can all open the picture up and see the detail. Near as they could count, that fish was 34 or 35 years old.