Maturation and sexual ontogeny in the spangled emperor Lethrinus nebulosus

Authors

R. J. Marriott, Department of Fisheries, Western Australia
N. D. C. Jarvis, Department of Fisheries, Western AustraliaFollow
D. J. Adams, Department of Fisheries, Western Australia
A. E. Gallash, Department of Fisheries, Western Australia
Jeffrey V. Norriss, Department of Fisheries, Western AustraliaFollow
Stephen J. Newman, Department of Fisheries, Western AustraliaFollow

Document Type

Article

Publication Date

4-23-2010

Journal Title

Journal of Fish Biology

ISSN

Print: 0022-1112 Electronic: 1095-8649

Keywords

Age estimation; Functional gonochorism, Gonadal development, Lethrinidae, Non-functional protogynous, Hermaphrodite

Disciplines

Aquaculture and Fisheries | Behavior and Ethology | Comparative and Evolutionary Physiology | Genetics | Marine Biology | Natural Resources and Conservation | Natural Resources Management and Policy | Population Biology | Sustainability

Abstract

The reproductive development and sexual ontogeny of spangled emperor Lethrinus nebulosus populations in the Ningaloo Marine Park (NMP) were investigated to obtain an improved understanding of its evolved reproductive strategy and data for fisheries management. Evidence derived from (1) analyses of histological data and sampled sex ratios with size and age, (2) the identification of residual previtellogenic oocytes in immature and mature testes sampled during the spawning season and (3) observed changes in testis internal structure with increasing fish size and age, demonstrated a non-functional protogynous hermaphroditic strategy (or functional gonochorism). All the smallest and youngest fish sampled were female until they either changed sex to male at a mean 277·5 mm total length (LT) and 2·3 years old or remained female and matured at a larger mean LT (392·1 mm) and older age (3·5 years). Gonad masses were similar for males and females over the size range sampled and throughout long reproductive lives (up to a maximum estimated age of c. 31 years), which was another correlate of functional gonochorism. That the mean LT at sex change and female maturity were below the current minimum legal size (MLS) limit (410 mm) demonstrated that the current MLS limit is effective for preventing recreational fishers in the NMP retaining at least half of the juvenile males and females in their landed catches.

Recommended Citation

Marriott, R.J., Jarvis, N.D.C., Adams, D.J., Gallash, A.E., Norriss, J. and Newman, S.J. (2010), Maturation and sexual ontogeny in the spangled emperor Lethrinus nebulosus. Journal of Fish Biology, 76: 1396-1414. https://doi.org/10.1111/j.1095-8649.2010.02571.x