Revista de Biología Tropical ISSN Impreso: 0034-7744 ISSN electrónico: 2215-2075

OAI: https://revistas.ucr.ac.cr/index.php/rbt/oai
Population structure and reproductive biology of Astyanax gymnodontus (Characiformes: Characidae), a poorly known endemic fish of the Iguaçu River basin, Brazil
PDF
HTML

Keywords

Reproductive biology
gonadosomatic index
RAI
fish ecology.
biología reproductiva
índice gonadosomático
IAR
ecología de peces

How to Cite

Baumgartner, M. T., Leandro da Silva, P. R., & Baumgartner, G. (2016). Population structure and reproductive biology of Astyanax gymnodontus (Characiformes: Characidae), a poorly known endemic fish of the Iguaçu River basin, Brazil. Revista De Biología Tropical, 64(1), 69–77. https://doi.org/10.15517/rbt.v64i1.18100

Abstract

Success in fish breeding depends on reproduction intensity, periodicity and the place where it occurs. Information about fish species reproduction is important to assist managers, and to determine conservation and management strategies. The fish assemblage of the Iguaçu River basin is already known for its high endemism, and despite this privilege, the large number of dams built along it, threat this particular biodiversity. Astyanax gymnodontus is an endemic fish species and studies on its population structure and reproductive biology are important, since they represent the first step for further community studies. Our objective was to evaluate some aspects of the population structure and reproductive biology of A. gymnodontus in the influence area of Salto Santiago dam, Iguaçu River, Paraná State, Brazil. Sampling was made monthly from July 2003 to June 2005, and bimonthly from July 2005 to March 2013, at five sites in the influence area of Salto Santiago dam. Fishes were collected using 10 m length gillnets with meshes ranging from 2.5 to 6.0 cm between non-adjacent knots and trammel nets with inner meshes of 6.0 cm between non-adjacent knots. Nets were arranged on surface, bottom and margins of each site, exposed for 24 h. Additional drags on littoral areas were performed from January to March and October to December from 2009 to 2011, with 50.0 m nets, 0.5 cm mesh size, for juveniles capture. We captured and analyzed 21 932 individuals, being 9 249 females and 12 683 males, representing 42.2 % and 57.8 %, respectively. The average body length was 8.8 cm for females and 8.3 cm for males. The average weight was 18.8 g for females and 16.0 g for males. Sex ratio calculated for the entire period was 1.8 males/female. Males were more abundant than females in 73.2 % of samples and significant differences were observed in 35.3 % of samples. The estimated length at first maturity (SL50) was 6.4 cm for females and 6.2 cm for males. We suggest that sexual differences in body length and weight, and sex ratio occurred as a result of sexual differences in energy allocation. Females spend more energy on body growth, which means more eggs production and higher fecundity. As an integrated response, males spend more energy on sperm production, in competition with other males, leading to a smaller body size. Differences in estimated SL50 might be an indicator of this sexual difference in energy allocation. The reproduction period was from September to February, with greater intensity at the beginning of this period, and the sites of highest reproductive intensity were those immediate downstream from dams, and therefore with more riverine characteristics.

https://doi.org/10.15517/rbt.v64i1.18100
PDF
HTML

References

Alcaraz, H. S. V., Pavanelli, C. S., & Bertaco, V. A. (2009). Astyanax jordanensis (Ostariophysi: Characidae), a new species from the rio Iguaçu basin, Paraná, Brazil. Neotropical Ichthyology, 7(2), 185-190.

Allen, C. R., Garmestani, A. S., Havlicek, T. D., Marquet, P. A., Peterson, G. D., Restrepo, C., Stow, C. A., & Weeks, B. E. (2006). Patterns in body mass distributions: shifting among alternative hypotheses. Ecology Letters, 9, 630-643.

Baumgartner, D., Baumgartner, G., Pavanelli, C. S., Silva, P. R. L., Frana, V. A., Oliveira, L. C., & Michelon, M. R. (2006). Fish, Salto Osório Reservoir, Iguaçu River basin, Paraná State, Brazil. Check List, 2(1), 1-4.

Baumgartner, G., Pavanelli, C. S., Baumgartner, D., Bifi, A. G., Debona, T., & Frana, V. A. (2012). Peixes do baixo rio Iguaçu. Maringá: Eduem.

Brown-Peterson, N. J., Wyanski, D. M., Saborido-Rey, F., Macewicz, B. J., & Lowerre-Barbieri, S. K. (2011). A standardized terminology for describing reproductive development in fishes. Marine and Coastal Fisheries: Dynamics, Management, and Ecosystem Science, 3(1), 52-70.

Cassemiro, F. A. S., Hahn, N. S., & Delariva, R. L. (2005). Estrutura trófica da ictiofauna, ao longo do gradiente longitudinal do reservatório de Salto Caxias (rio Iguaçu, Paraná, Brasil), no terceiro ano após o represamento. Acta Scientiarum. Biological Sciences, 7(1), 63-71.

Fonteles-Filho, A. A. (1989). Recursos pesqueiros: biologia e dinâmica populacional. Fortaleza: Imprensa Oficial do Ceará.

Garavello, J. C., Pavanelli, C. S., & Suzuki, H. I. (1997). Caracterização da Ictiofauna do Rio Iguaçu. In A. A. Agostinho, & L. C. Gomes (Eds.), Reservatório de Segredo: bases ecológicas para o manejo (pp. 61-84). Maringá: Eduem.

Graça, W. J., & Pavanelli, C. S. (2007). Peixes da planície de inundação do alto rio Paraná e áreas adjacentes. Maringá: Eduem.

Hahn, N. S., Fugi, R., Almeida, V. L. L., Russo, M. R., & Loureiro, V. E. (1997). Dieta e atividade alimentar de peixes do reservatório de Segredo. In A. A. Agostinho, & L. C. Gomes (Eds.), Reservatório de Segredo: bases ecológicas para o manejo (pp. 141-162). Maringá: Eduem.

Ingenito, L. F. S., Duboc, L. F., & Abilhoa, V. (2004). Contribuição ao conhecimento da ictiofauna da bacia do alto rio Iguaçu, Paraná, Brasil. Arquivos de Ciências Veterinárias e Zoologia da UNIPAR, 7(1), 23-36.

Loureiro-Crippa, V. E., & Hahn, N. S. (2006). Use of food resources by the fish fauna of a small reservoir (rio Jordão, Brazil) before and shortly after its filling. Neotropical Ichthyology, 4(3), 357-362.

Mise, F. T., Fugi, R., Pagotto, J. P. A., & Goulart, E. (2013). The coexistence of endemic species of Astyanax (Teleostei: Characidae) is propitiated by ecomorphological and trophic variations. Biota Neotropica, 13(3), 21-28.

Morita, K., Yamamoto, S., Takashima, Y., Matsuishi, T., Kanno, Y., & Nishimura, K. (1999). Effect on maternal growth on egg and size in wild white-spotted char (Salvelinus luecomaenis). Canadian Journal of Fisheries and Aquatic Siences, 56, 1585-1589.

Nikolsky, G. V. (1963). The Ecology of Fishes. London: Academy Press.

Parker, G. A. (1982). Why are there so many tiny sperm? Sperm competition and the maintenance of two sexes. Journal of Theoretical Biology, 96, 281-294.

Pavanelli, C. S., & Oliveira, C. A. M. (2009). A redescription of Astyanax gymnodontus (Eigenmann, 1911), new combination, a polymorphic characid fish from the rio Iguaçu basin, Brazil. Neotropical Ichthyology, 7(4), 569-578.

Pavlov, D. S., & Kasumyan, A. O. (2000). Patterns and mechanisms of schooling behavior in fish: a review. Journal of Ichthyology, 40(2), 163-231.

R Core Team (2014). R: A language and environment for statistical computing. Vienna: R Foundation for Statistical Computing.

Reis, R. E., Kullander, S. O., & Ferraris Junior, C. J. (2003). Check list of freshwater fishes of South and Central America. Porto Alegre: Edipucrs.

Shine, R. (1990). Proximate determinants of sexual differences in body size. American Naturalist, 135(2), 278-283.

Suzuki, H. I., & Agostinho, A. A. (1997). Reprodução de peixes do reservatório de Segredo. In A. A. Agostinho, & L. C. Gomes (Eds.). Reservatório de Segredo: Bases Ecológicas para o Manejo (pp. 163-182). Maringá: Eduem.

Tractebel Energia, & Ecsa. (2002). Plano de uso e ocupação das águas e entorno do reservatório da usina hidroelétrica Salto Santiago. Curitiba: Instituto Ambiental do Paraná.

Vazzoler, A. E. A. M. (1996). Biologia da Reprodução de Peixes Teleósteos: Teoria e Prática. Maringá: Eduem.

Wootton, R. J. (1984). Introduction: strategies and tactics in fish reproduction. In G. W. Potts, & R. J. Wootton (Eds.). Fish Reproduction: strategies and tactics (pp. 1-12). London: Academic Press.

Wootton, R. J. (1990). Ecology of teleost fishes. London: Chapman & Hall.

Comments

Creative Commons License

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

Copyright (c) 2016 Revista de Biología Tropical

Downloads

Download data is not yet available.