TY - JOUR
T1 - Comparison between surface-reading and cross-section methods using sagittal otolith for age determination of the marbled sole Pseudopleuronectes yokohamae
AU - Lee, Jeong Hoon
AU - Kodama, Keita
AU - Kume, Gen
AU - Oyama, Masaaki
AU - Katayama, Satoshi
AU - Takao, Yuji
AU - Horiguchi, Toshihiro
PY - 2009/2
Y1 - 2009/2
N2 - To find an appropriate method for age determination in the marbled sole Pseudopleuronectes yokohamae in Tokyo Bay, Japan, sagittal otoliths of 1,343 individuals were observed by surface-reading and cross-section methods and the results were compared. Opaque zones occurred once a year and were regarded as annuli in both methods. The surface-reading method sometimes provided a lower count of the number of annuli than the cross-section method, and the frequency of this discrepancy was highest in older fish (males above 5 years, females above 4 years). The oldest female fish was estimated to be age 10 years by the cross-section method but 8 years by the surface-reading method. The cross-section method could provide a more accurate estimate of age and is therefore likely to be indispensable to estimations of longevity. In contrast, the surface-reading method is superior in terms of cost and time efficiency but is likely to underestimate the ages of older fish. However, growth equations based on age estimated by the surface-reading method were sufficiently accurate if males ≥5 years and females ≥4 years were combined as specific, single age groups of 5+ and 4+, respectively.
AB - To find an appropriate method for age determination in the marbled sole Pseudopleuronectes yokohamae in Tokyo Bay, Japan, sagittal otoliths of 1,343 individuals were observed by surface-reading and cross-section methods and the results were compared. Opaque zones occurred once a year and were regarded as annuli in both methods. The surface-reading method sometimes provided a lower count of the number of annuli than the cross-section method, and the frequency of this discrepancy was highest in older fish (males above 5 years, females above 4 years). The oldest female fish was estimated to be age 10 years by the cross-section method but 8 years by the surface-reading method. The cross-section method could provide a more accurate estimate of age and is therefore likely to be indispensable to estimations of longevity. In contrast, the surface-reading method is superior in terms of cost and time efficiency but is likely to underestimate the ages of older fish. However, growth equations based on age estimated by the surface-reading method were sufficiently accurate if males ≥5 years and females ≥4 years were combined as specific, single age groups of 5+ and 4+, respectively.
KW - Age determination
KW - Cross-section method
KW - Growth
KW - Otolith
KW - Pseudopleuronectes yokohamae
KW - Surface-reading method
KW - Tokyo Bay
UR - http://www.scopus.com/inward/record.url?scp=67849103748&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=67849103748&partnerID=8YFLogxK
U2 - 10.1007/s12562-009-0065-5
DO - 10.1007/s12562-009-0065-5
M3 - Article
AN - SCOPUS:67849103748
VL - 75
SP - 379
EP - 385
JO - Fisheries Science
JF - Fisheries Science
SN - 0919-9268
IS - 2
ER -