2006-11-23 03:36:04 · 10 answers · asked by Busyman 1 in Science & Mathematics ➔ Zoology
In temperate areas where there there are seasonal differences, the number of rings on the scales like the rings on a tree, as well as the number of layers on otoliths (basically a bone in the inner ear) is a good indicator of age. However it doesn't work in warm environments because fish growth is constant and you can't make out the different rings. When its hot there is a period of rapid growth, and when the temp drops growth slows down, this is basically what you see on there. Unfortunately size estimates aren't usefull as not every fish will grow at the same rate, for example a 5 year old bass in one area may be smaller than a 3 year old in another.
2006-11-23 03:50:24 · answer #1 · answered by crazy.carabid 4 · 1⤊ 1⤋
I am not sure about this, but I thought I heard once that fish scales have
rings similar to tree rings and you can tell the age of the fish by the
number of rings on their scales. I am also not sure if this applies to all
fish species.
In most bony fishes, many of the scales and bones show seasonal growth (more
obvious in the temperate zones)that can be observed. Since most bony fish never
stop growing (some notable exceptions here, scientist have a means to determine
age.
2006-11-23 03:56:08 · answer #2 · answered by deep s 2 · 0⤊ 1⤋
Many fish can be aged by the annular rings on the scales...many of the smaller varieties live less than three years but on carp which have a life span of 40 plus years, removing a scale and with a microscope, you can count the annular rings. It is similar to trees. We see most growth during the spring and summer and small growth during the cooler periods.
2006-11-23 03:48:15 · answer #3 · answered by Frank 6 · 0⤊ 1⤋
Just count the number of lines on one of the fishes scales
2006-11-23 03:55:11 · answer #4 · answered by Dan A 2 · 0⤊ 2⤋
well if you are serious only . it basically depends on the type of fish but a uniforn rule is followed. it is based on the length, hight (top fin ) and the size of scales. normally fish technicians have a standard charts for each species. long and big scales means older fish. if you need the chard you can download or mail me. "" fish do look older during full moon""(mating time yooohooo)
2006-11-23 03:52:36 · answer #5 · answered by srini 3 · 0⤊ 2⤋
Either count their rings ( 1 per year) or check their teeth (the more wear they show the older they are) No.....wait a minute.....that's for trees and horses. For fish, I don't know for sure so excuse me------NO NO!!! I JUST REMEMBERED!!!
The worse they smell the older they are. I once had some fish in my car trunk and boy, could you ever tell they were getting older.
2006-11-23 07:23:37 · answer #6 · answered by JIMBO 4 · 0⤊ 2⤋
by the growth rings on its scales
2006-11-26 10:20:08 · answer #7 · answered by hill bill y 6 · 0⤊ 1⤋
Cut them open and count the rings inside. ;)
2006-11-23 03:37:36 · answer #8 · answered by allgrainmonster 2 · 0⤊ 2⤋
Ask the fish, moron.
2006-11-23 03:38:10 · answer #9 · answered by az_ zoo 2 · 0⤊ 2⤋
well thats easy u just look at the fish and see if it has alot of wrinkles and if it does then its old!!! duh! =)
Its the same way u see if humans are old or not!
2006-11-23 03:45:37 · answer #10 · answered by Eureka! 6 · 0⤊ 2⤋