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Name: Belinda Clark
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Question:
In my daughter's book about fish, it states that fish continue to get bigger as they age and that you can tell how old a fish is by counting the rings on its scales. Does this mean that a fish is born with all of its scales and as the fish grows, the scales also grow to cover the fish?



Replies:
According to my fish expert, fish will not normally lose scales unless injured. They do have growth rings just like trees, and from this age can be determined. However, to get very accurate ages, one must do laboratory experiments to correlate the rings with age. In addition, if a scale is lost, it will grow back all at one time, and not exhibit any growth rings until the next growth season. From then on, it will add rings at the same rate as the other scales. Females may not add growth rings when they are reproducing, as all their energy is used in egg production. To further confuse things, some females will grow, stop while reproducing, then grow some more, and this will cause one growth season to look like two rings. This is why the laboratory experiments are needed.

Stacie, with help from fish expert Chris.



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