Sexual maturity, spawning and fecundity of king weakfish Macrodon ancylodon, caught off Rio Grande do Sul State (southern coast of Brazil)

Juras, Anastácio Afonso; Yamaguti, Noriyoshi

doi:10.1590/S0373-55241989000100005

Abstract

Investigations on the sexual maturity, spawning and fecundity of king weakfish, Macrodon ancylodon, off the southern coast of Brazil (lat. 29º to 32ºS) were carried out from September, 1976, to August, 1977. The sex ratio varied monthly, with slight predominance of males (51.14%) over females (48.86%). The mean size at first maturity was estimated as 27.4 cm TL for females and 21.5 cm TL for males. The macroscopic examination of gonads and analysis of the gonadal index indicated that December and February were the most intensive spawning months. Fish weight proved to be the best predictor data of fecundity: F = 17056.2500 + 425.3712 Wt (r² = 0.6434) , were F is the total number of eggs in both ovaries. The number of eggs of 199 females varied from 59,850 for 33.4 cm TL fish to over 358,450 for 37.2 cm TL; the mean fecundity verified was 165,273 eggs per female. Frequency distributions of egg diameter in the ovaries were polymodal, suggesting fractional spawning during the reproduction season.

Sex ratio; Sexual maturity; Spawning seasons; Fecundity; Macrodon ancylodon; Brazil

ARTIGOS

Sexual maturity, spawning and fecundity of king weakfish Macrodon ancylodon, caught off Rio Grande do Sul State (southern coast of Brazil)

Anastácio Afonso Juras^* (* ) Centrais Elétricas do Norte do Brasil S.A. Setor SCN, Bloco B, Quadra 6, Brasília - CEP 70.710 ; Noriyoshi Yamaguti

Instituto Oceanográfico da Universidade de São Paulo (Caixa Postal 9075, 01051 São Paulo, SP)

ABSTRACT

Investigations on the sexual maturity, spawning and fecundity of king weakfish, Macrodon ancylodon, off the southern coast of Brazil (lat. 29º to 32ºS) were carried out from September, 1976, to August, 1977. The sex ratio varied monthly, with slight predominance of males (51.14%) over females (48.86%). The mean size at first maturity was estimated as 27.4 cm TL for females and 21.5 cm TL for males. The macroscopic examination of gonads and analysis of the gonadal index indicated that December and February were the most intensive spawning months. Fish weight proved to be the best predictor data of fecundity: F = 17056.2500 + 425.3712 Wt (r² = 0.6434) , were F is the total number of eggs in both ovaries. The number of eggs of 199 females varied from 59,850 for 33.4 cm TL fish to over 358,450 for 37.2 cm TL; the mean fecundity verified was 165,273 eggs per female. Frequency distributions of egg diameter in the ovaries were polymodal, suggesting fractional spawning during the reproduction season.

Descriptors: Sex ratio, Sexual maturity, Spawning seasons, Fecundity, Macrodon ancylodon, Brazil: Rio Grande do Sul.

Descritores: Proporção do sexo, Maturação sexual, Época de desova, Fecundidade, Macrodon ancylodon, Rio Grande do Sul.

Full text available only in PDF format.

Texto completo disponível apenas em PDF.

Acknowledgments

The authors are very grateful to Ilidia da Ascenção Garrido Martins-Juras (MSc) for many helpful suggestions in the preparation of the manuscript. The research was partially supported by the Conselho Nacional de Desenvolvimento Científico e Tecnológico -CNPq.

(Recebido em 07-03-86; aceito em 16-10-89)

ALHEIT; J.; ALARCON, V. H. & MACEWICZ, B. J. 1984. Spawning frequency and sex ratio in Peruvian anchovy. Calif, coop, ocean. Fish. Invest. Rep., 25:43-52.
BAGENAL, T. B. 1973. Fish fecundity and its relations with stock and recruitment. Rapp. P.-v. Réun. Cons, perm. Int. Explor. Mer, 764:186-198.
______ & BRAUM, E. 1971. Eggs and early life history. In: Ricker, W. E.,ed. Methods for assessment of fish production in fresh waters. 2^nd ed. London, International Biological Programme. p.166-198.
DE MARTINI, E. E. & FOUNTAIN, R.K. 1981. Ovarian cycling frequency and batch fecundity in the queenfish, Seriphus politus: attributes representative of serial spawning fishes. Fishery Bull. natn. mar. Fish. Serv, U.S, 79(3):547-560.
GULLAND, J. A. 1971. Manual de métodos para la evaluación de las poblaciones de peces. Zaragoza, Edit. Acribia/FAO. 164p.
HUNTER, J. R. & GOLDBERG, S. R. 1980. Spawning incidence and batch fecundity in northern anchovy, Engraulis mordax. Fishery Bull. natn. mar. Fish. Serv., U.S. 77(3):641-652.
______ & LEONG, R. 1981. The spawning energetics of female northern anchovy, Engraulis mordax. Fishery Bull. natn. mar. Fish. Serv., U.S. 79(2):215-230.
______; LO, N. C. H. & LEONG, J. H. 1984. Batch fecundity in multiple spawning fishes. In: Lasker, R., ed. An egg production method for estimating spawning biomass of pelagic fish: application to the northern anchovy, Engraulis mordax, U.S. Dep. Commer., NOAA Administrative Report LJ-84-37.p.204-246.
LAEVASTU, T. 1971. Manual de métodos de biologia pesquera. Zaragoza, Edit. Acribia/FAO. 243 p.
LARA, E J. S. 1951. A study of the life history of Macrodon ancylodon (Bloch & Schneider) a sciaenid fish occurring on the coast of southern Brazil Anais Acad. bras. Cienc., 23(3):291- 322.
MACER, C. T. 1974. The reproductive biology of the horse mackerel Trachurus trachurus (L.) in the North Sea and English Channel J. Fish. Biol, 6(3):415-438.
MacGREGOR, J. S. 1968. Fecundity of the northern anchovy, Engraulis mordax Girard. Calif. Fish Game, 54:281-288.
NIKOLSKY, G. V. 1969. Theory of fish population dynamics as the biological background for rational exploitation and management of fishery resources. Edinburg, Olivier & Boyd. 323 p.
SIMPSON, A. C. 1951. The fecundity of the plaice. Fisheries Invest., Lond., ser. 2, 17(5): 1-27.
STEQUERT, S. 1976. Étude de la maturité sexualle, de la ponte et de la fécondité du listão (Ketsuwonus pelamis) de la côte nord-ouest de Madagascar. Cah. ORSTOM, sér. Océanogr., 14(3):227- 247.
TEMPLEMAN, W.; HODDER, V M. & WELLS, R. 1978. Age, growth, year-class strength, and mortality of the haddock, Melanogrammus aeglefinus, on the southern Grand Bank and their relation to the haddock fishery of this area. Res. Bull. int. Comran NW Atlantic Fish., (13):31-52.
VAZZOLER, A. E. A. de M. 1963. Sobre a fecundidade e a desova da pescada-foguete. Bolm Inst, oceanogr., S Paulo, 13(2):33-40.
______1965. Relative spawning power of Macrodon ancylodon (Bloch) population in the southern coast of Brazil. Anais Acad. bras. Ciênc, 37 (supl.):365-370.
______ ; ZANETI, E. M. & KAWAKAMI, E. 1973. Estudo preliminar sobre o ciclo de vida dos Sciaenidae. Parte I, Composição da população em classes de comprimento e aspectos da reprodução. Publção esp. Inst. oceanogr., S Paulo, (3, pt. 1):241- 291.
WARE, F. M. 1975. Relation between egg size, growth, and natural mortality of larval fish. Res. Ed. Can., 32:2503-2512.
YAMAGUTI, N. 1967. Desova da pescada-foguete, Macrodon ancylodon. Bolm Inst, oceanogr., S Paulo, 16(1):101-106.

(*

) Centrais Elétricas do Norte do Brasil S.A. Setor SCN, Bloco B, Quadra 6, Brasília - CEP 70.710

Publication Dates

Publication in this collection
04 June 2012
Date of issue
1989

History

Received
07 Mar 1986
Accepted
16 Oct 1989

This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.

[1] ALHEIT; J.; ALARCON, V. H. & MACEWICZ, B. J. 1984. Spawning frequency and sex ratio in Peruvian anchovy. Calif, coop, ocean. Fish. Invest. Rep., 25:43-52.

[2] BAGENAL, T. B. 1973. Fish fecundity and its relations with stock and recruitment. Rapp. P.-v. Réun. Cons, perm. Int. Explor. Mer, 764:186-198.

[3] ______ & BRAUM, E. 1971. Eggs and early life history. In: Ricker, W. E.,ed. Methods for assessment of fish production in fresh waters. 2^nd ed. London, International Biological Programme. p.166-198.

[4] DE MARTINI, E. E. & FOUNTAIN, R.K. 1981. Ovarian cycling frequency and batch fecundity in the queenfish, Seriphus politus: attributes representative of serial spawning fishes. Fishery Bull. natn. mar. Fish. Serv, U.S, 79(3):547-560.

[5] GULLAND, J. A. 1971. Manual de métodos para la evaluación de las poblaciones de peces. Zaragoza, Edit. Acribia/FAO. 164p.

[6] HUNTER, J. R. & GOLDBERG, S. R. 1980. Spawning incidence and batch fecundity in northern anchovy, Engraulis mordax. Fishery Bull. natn. mar. Fish. Serv., U.S. 77(3):641-652.

[7] ______ & LEONG, R. 1981. The spawning energetics of female northern anchovy, Engraulis mordax. Fishery Bull. natn. mar. Fish. Serv., U.S. 79(2):215-230.

[8] ______; LO, N. C. H. & LEONG, J. H. 1984. Batch fecundity in multiple spawning fishes. In: Lasker, R., ed. An egg production method for estimating spawning biomass of pelagic fish: application to the northern anchovy, Engraulis mordax, U.S. Dep. Commer., NOAA Administrative Report LJ-84-37.p.204-246.

[9] LAEVASTU, T. 1971. Manual de métodos de biologia pesquera. Zaragoza, Edit. Acribia/FAO. 243 p.

[10] LARA, E J. S. 1951. A study of the life history of Macrodon ancylodon (Bloch & Schneider) a sciaenid fish occurring on the coast of southern Brazil Anais Acad. bras. Cienc., 23(3):291- 322.

[11] MACER, C. T. 1974. The reproductive biology of the horse mackerel Trachurus trachurus (L.) in the North Sea and English Channel J. Fish. Biol, 6(3):415-438.

[12] MacGREGOR, J. S. 1968. Fecundity of the northern anchovy, Engraulis mordax Girard. Calif. Fish Game, 54:281-288.

[13] NIKOLSKY, G. V. 1969. Theory of fish population dynamics as the biological background for rational exploitation and management of fishery resources. Edinburg, Olivier & Boyd. 323 p.

[14] SIMPSON, A. C. 1951. The fecundity of the plaice. Fisheries Invest., Lond., ser. 2, 17(5): 1-27.

[15] STEQUERT, S. 1976. Étude de la maturité sexualle, de la ponte et de la fécondité du listão (Ketsuwonus pelamis) de la côte nord-ouest de Madagascar. Cah. ORSTOM, sér. Océanogr., 14(3):227- 247.

[16] TEMPLEMAN, W.; HODDER, V M. & WELLS, R. 1978. Age, growth, year-class strength, and mortality of the haddock, Melanogrammus aeglefinus, on the southern Grand Bank and their relation to the haddock fishery of this area. Res. Bull. int. Comran NW Atlantic Fish., (13):31-52.

[17] VAZZOLER, A. E. A. de M. 1963. Sobre a fecundidade e a desova da pescada-foguete. Bolm Inst, oceanogr., S Paulo, 13(2):33-40.

[18] ______1965. Relative spawning power of Macrodon ancylodon (Bloch) population in the southern coast of Brazil. Anais Acad. bras. Ciênc, 37 (supl.):365-370.

[19] ______ ; ZANETI, E. M. & KAWAKAMI, E. 1973. Estudo preliminar sobre o ciclo de vida dos Sciaenidae. Parte I, Composição da população em classes de comprimento e aspectos da reprodução. Publção esp. Inst. oceanogr., S Paulo, (3, pt. 1):241- 291.

[20] WARE, F. M. 1975. Relation between egg size, growth, and natural mortality of larval fish. Res. Ed. Can., 32:2503-2512.

[21] YAMAGUTI, N. 1967. Desova da pescada-foguete, Macrodon ancylodon. Bolm Inst, oceanogr., S Paulo, 16(1):101-106.