Age estimation and validation for South Pacific albacore Thunnus alalunga

J. H. Farley, A. J. Williams, N. P. Clear, C. R. Davies, S. J. Nicol

Research output: Contribution to journalArticle

15 Citations (Scopus)

Abstract

Validated estimates of age are presented for albacore Thunnus alalunga, sampled from a large part of the south-western Pacific Ocean, based on counts of annual opaque growth zones from transverse sections of otoliths. Counts of daily increments were used to estimate the location of the first opaque growth zone, which was completed before the first assumed birthday. The periodicity of opaque zones was estimated by marginal increment analysis and an oxytetracycline mark-recapture experiment. Both validation methods indicated that opaque zones formed over the austral summer and were completed by autumn to winter (April to August). The direct comparison of age estimates obtained from otoliths and dorsal-fin spines of the same fish indicated bias, which was assumed to be due to poor increment clarity and resorption of early growth zones in spines, resulting in imprecise age estimates. As such, age estimates from otoliths are considered to be more accurate than those from spines for T. alalunga. This is consistent with results for a growing number of tropical and temperate tuna Thunnini species. It is recommend that validated counts of annual growth zones from sectioned otoliths is used as the preferred method for estimating age-based parameters for assessment and management advice for these important stocks.

Original languageEnglish
Pages (from-to)1523-1544
Number of pages22
JournalJournal of Fish Biology
Volume82
Issue number5
DOIs
Publication statusPublished - 1 May 2013
Externally publishedYes

Fingerprint

Thunnus alalunga
otoliths
otolith
spine (bones)
tuna
resorption
oxytetracycline
Pacific Ocean
periodicity
fins
autumn
winter
summer
methodology
fish
ocean

Cite this

Farley, J. H., Williams, A. J., Clear, N. P., Davies, C. R., & Nicol, S. J. (2013). Age estimation and validation for South Pacific albacore Thunnus alalunga. Journal of Fish Biology, 82(5), 1523-1544. https://doi.org/10.1111/jfb.12077
Farley, J. H. ; Williams, A. J. ; Clear, N. P. ; Davies, C. R. ; Nicol, S. J. / Age estimation and validation for South Pacific albacore Thunnus alalunga. In: Journal of Fish Biology. 2013 ; Vol. 82, No. 5. pp. 1523-1544.
@article{5c920166d9024b2080d1572ee3dcb513,
title = "Age estimation and validation for South Pacific albacore Thunnus alalunga",
abstract = "Validated estimates of age are presented for albacore Thunnus alalunga, sampled from a large part of the south-western Pacific Ocean, based on counts of annual opaque growth zones from transverse sections of otoliths. Counts of daily increments were used to estimate the location of the first opaque growth zone, which was completed before the first assumed birthday. The periodicity of opaque zones was estimated by marginal increment analysis and an oxytetracycline mark-recapture experiment. Both validation methods indicated that opaque zones formed over the austral summer and were completed by autumn to winter (April to August). The direct comparison of age estimates obtained from otoliths and dorsal-fin spines of the same fish indicated bias, which was assumed to be due to poor increment clarity and resorption of early growth zones in spines, resulting in imprecise age estimates. As such, age estimates from otoliths are considered to be more accurate than those from spines for T. alalunga. This is consistent with results for a growing number of tropical and temperate tuna Thunnini species. It is recommend that validated counts of annual growth zones from sectioned otoliths is used as the preferred method for estimating age-based parameters for assessment and management advice for these important stocks.",
keywords = "Ageing protocols, Annual, Marginal increment analysis, Otoliths, Spines",
author = "Farley, {J. H.} and Williams, {A. J.} and Clear, {N. P.} and Davies, {C. R.} and Nicol, {S. J.}",
year = "2013",
month = "5",
day = "1",
doi = "10.1111/jfb.12077",
language = "English",
volume = "82",
pages = "1523--1544",
journal = "Journal of Fish Biology",
issn = "0022-1112",
publisher = "Wiley-Blackwell",
number = "5",

}

Farley, JH, Williams, AJ, Clear, NP, Davies, CR & Nicol, SJ 2013, 'Age estimation and validation for South Pacific albacore Thunnus alalunga', Journal of Fish Biology, vol. 82, no. 5, pp. 1523-1544. https://doi.org/10.1111/jfb.12077

Age estimation and validation for South Pacific albacore Thunnus alalunga. / Farley, J. H.; Williams, A. J.; Clear, N. P.; Davies, C. R.; Nicol, S. J.

In: Journal of Fish Biology, Vol. 82, No. 5, 01.05.2013, p. 1523-1544.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Age estimation and validation for South Pacific albacore Thunnus alalunga

AU - Farley, J. H.

AU - Williams, A. J.

AU - Clear, N. P.

AU - Davies, C. R.

AU - Nicol, S. J.

PY - 2013/5/1

Y1 - 2013/5/1

N2 - Validated estimates of age are presented for albacore Thunnus alalunga, sampled from a large part of the south-western Pacific Ocean, based on counts of annual opaque growth zones from transverse sections of otoliths. Counts of daily increments were used to estimate the location of the first opaque growth zone, which was completed before the first assumed birthday. The periodicity of opaque zones was estimated by marginal increment analysis and an oxytetracycline mark-recapture experiment. Both validation methods indicated that opaque zones formed over the austral summer and were completed by autumn to winter (April to August). The direct comparison of age estimates obtained from otoliths and dorsal-fin spines of the same fish indicated bias, which was assumed to be due to poor increment clarity and resorption of early growth zones in spines, resulting in imprecise age estimates. As such, age estimates from otoliths are considered to be more accurate than those from spines for T. alalunga. This is consistent with results for a growing number of tropical and temperate tuna Thunnini species. It is recommend that validated counts of annual growth zones from sectioned otoliths is used as the preferred method for estimating age-based parameters for assessment and management advice for these important stocks.

AB - Validated estimates of age are presented for albacore Thunnus alalunga, sampled from a large part of the south-western Pacific Ocean, based on counts of annual opaque growth zones from transverse sections of otoliths. Counts of daily increments were used to estimate the location of the first opaque growth zone, which was completed before the first assumed birthday. The periodicity of opaque zones was estimated by marginal increment analysis and an oxytetracycline mark-recapture experiment. Both validation methods indicated that opaque zones formed over the austral summer and were completed by autumn to winter (April to August). The direct comparison of age estimates obtained from otoliths and dorsal-fin spines of the same fish indicated bias, which was assumed to be due to poor increment clarity and resorption of early growth zones in spines, resulting in imprecise age estimates. As such, age estimates from otoliths are considered to be more accurate than those from spines for T. alalunga. This is consistent with results for a growing number of tropical and temperate tuna Thunnini species. It is recommend that validated counts of annual growth zones from sectioned otoliths is used as the preferred method for estimating age-based parameters for assessment and management advice for these important stocks.

KW - Ageing protocols

KW - Annual

KW - Marginal increment analysis

KW - Otoliths

KW - Spines

UR - http://www.scopus.com/inward/record.url?scp=84876903524&partnerID=8YFLogxK

U2 - 10.1111/jfb.12077

DO - 10.1111/jfb.12077

M3 - Article

VL - 82

SP - 1523

EP - 1544

JO - Journal of Fish Biology

JF - Journal of Fish Biology

SN - 0022-1112

IS - 5

ER -

Farley JH, Williams AJ, Clear NP, Davies CR, Nicol SJ. Age estimation and validation for South Pacific albacore Thunnus alalunga. Journal of Fish Biology. 2013 May 1;82(5):1523-1544. https://doi.org/10.1111/jfb.12077