Spatial and temporal length distribution of Zungaro zungaro caught in the Orinoco River Basin of Colombia

Spatial and temporal length distribution of Zungaro zungaro caught in the Orinoco River Basin of Colombia

ABSTRACT

Objetive. To determine the effect of fishing on capture size of both male and female Zungaro zungaro catfish, historical records of size and spatial distribution of the species were analyzed from the Orinoco Basin in Colombian. Materials and methods. Information was collected by sampling fishing port landings in the region between 1979 and 2011. Each specimen was measured, weighed and sexed. With 5411 records, the average size at capture were compared in time and among the different ports. Size at 50% maturity was estimated by quinquennium. Results. The average commercial capture sizes of Z. zungaro ranged from 35 to 161 cm standard length, with differences between males and females. From 1979 to 2011, in Puerto Lopez, the size at sexual maturity decreased from 123.8 to 83.4 cm in females and from 93.3 to 61 in males. In the annual cycle the greater average capture size in females was from April to July and for males from May to June. Average annual length is higher in the higher parts of the Meta and Guaviare river drainages. In the last quinquennium the size at 50% maturity had fallen 10 cm in females and 5 cm in males and it is higher than the average capture size. Conclusions. Populations of Z. zungaro in the Colombian Orinoco River Basin have been affected by overfishing and selective fishing of females.

RESUMEN

Objetivo. Determinar el grado de afección en la población de Zungaro zungaro a partir del análisis del comportamiento histórico y espacial de las tallas de captura de hembras y machos de la especie en la Orinoquia colombiana. Materiales y métodos. La información fue colectada mediante muestreos a los desembarcos en puertos pesqueros de la región entre 1979 y 2011. Cada ejemplar fue medido, pesado y sexado. Con 5411 registros, se estableció la distribución de las tallas medias de captura, que se compararon en el tiempo y entre los diferentes puertos. Se estimó la talla de madurez gonadal (TMG) por quinquenios. Resultados. El rango de las tallas de captura comercial Z. zungaro fue de 35 a 161 cm longitud estándar (LS), con diferencia entre machos y hembras. Entre los años 1979 a 2011, en Puerto López, la talla promedio de captura anual (LS) disminuyó de 123.8 a 83.4 cm en hembras y de 93.3 a 61 cm en machos. En el ciclo anual la mayor talla promedio de captura de hembras se presenta en abril a julio y de machos en mayo y junio. La talla promedio de captura anual (TPCA) es superior en las partes altas de los ríos Meta y Guaviare. En el último quinquenio la TMG ha disminuido 10 cm en las hembras y cinco cm en los machos y es superior a la TPCA. Conclusiones. Hay afectación sobre la población explotada de Z. zungaro por sobrepesca por crecimiento y pesca selectiva de hembras en la Orinoquia colombiana.

1. Boni TA, Padial AA, Prioli SMAP, Lucio LC, Maniglia TC, Bignotto TS et al. Molecular differentiation of species of the genus Zungaro (Siluriformes, Pimelodidae) from the Amazon and Paraná-Paraguay River basins in Brazil. Genet Mol Res 2011; 10(4):2795-2805. http://dx.doi.org/10.4238/2011.November.10.2
3. Lasso CA, Agudelo-Córdoba E, Jiménez-Segura LF, Ramírez-Gil H, Morales-Betancourt M, Ajiaco-Martínez, et al (Editores.) I. Catálogo de los Recursos Pesqueros continentales de Colombia. Serie Editorial Recursos Hidrobiológicos y Pesqueros continentales de Colombia. Bogotá, D.C., Colombia: Instituto de Investigación de Recursos Biológicos Alexander von Humboldt (IAvH). 2011; 537-541.
5. Machado-Allison A, Bottini B. Especies de la pesquería continental venezolana: un recurso natural en peligro. Bol Acad C Fís Mat y Nat 2010; 70(1):59-75.
7. Pérez-Lozano A, Barbarino A. Parámetros poblacionales de los principales recursos pesqueros de la cuenca del río Apure, Venezuela (2000-2003). Lat Am J Aquat Res 2013; 41(3):447-458.
9. Agostinho AA, Pelicice FM, Gomes LC. Dams and the fish fauna of the Neotropical region: impacts and management related to diversity and fisheries. Braz J Biol 2008; 68(4):1119-1132 http://dx.doi.org/10.1590/S1519-69842008000500019
11. Godinho AL, Reis I, Godinho H. Reproductive ecology of Brazilian freshwater fishes. Environ Biol Fish 2010; 87:143–162 http://dx.doi.org/10.1007/s10641-009-9574-4
13. Maldonado-Ocampo JA, Vari RP, Usma JS. Checklist of the freshwater fishes of Colombia. Biota Colombiana 2008; 9(2):143-237.
15. Lasso C, Usma JS, Villa F, Sierra-Quintero MT, Ortega-Lara A, Mesa LM, et al. Peces de la Estrella Fluvial Inírida: ríos Guaviare, Inírida, Atabapo y Orinoco, Orinoquía colombiana. Biota Colombiana 2009; 10(1-2):89–122.
17. Mojica JI, Usma JS, Alvarez-León R, Lasso CA (Editores). Libro rojo de peces dulceacuícolas de Colombia. Bogotá, D. C., Colombia: Instituto de Investigación de Recursos Biológicos Alexander von Humboldt, Instituto de Ciencias Naturales de la Universidad Nacional de Colombia, WWF Colombia, Universidad de Manizales. 2012; 192-195.
19. Mateus LAF, Penha JMF. Dinâmica populacional de quatro espécies de grandes bagres na bacia do rio Cuiabá, Pantanal norte, Brasil (Siluriformes, Pimelodidae). Rev Bras Zool 2007; 24(1):87-98. http://dx.doi.org/10.1590/S0101-81752007000100012
21. Fenberg P, Roy K. Ecological and evolutionary consequences of size-selective harvesting: how much do we know? Mol Ecol 2008; 17:209-220 http://dx.doi.org/10.1111/j.1365-294X.2007.03522.x
23. Longhurst A. The sustainability myth. Fish Res 2006; 81:107–112 http://dx.doi.org/10.1016/j.fishres.2006.06.022
25. Perry RI, Cury P, Brander K, Jennings S, Möllmann C, Planque B. Sensitivity of marine systems to climate and fishing: Concepts, issues and management responses. J Mar Syst 2010; 79(3):427-435. http://dx.doi.org/10.1016/j.jmarsys.2008.12.017
27. Rijnsdorp AD, Grift RE, Kraak SBM. Fisheries-induced adaptive change in reproductive investment in North Sea plaice (Pleuronectes platessa)? Can J Fish Aquat Sci 2005; 62(4):833-843. http://dx.doi.org/10.1139/f05-039
29. Enberg K, Jørgensen C, Dunlop E, Varpe O, Boukal D, Baulier L et al. Fishing-induced evolution of growth: concepts, mechanisms and the empirical evidence. Mar Ecol 2012; 33:1–25. http://dx.doi.org/10.1111/j.1439-0485.2011.00460.x
31. Alves CBM, Silva LGM, Godinho AL. Radiotelemetry of a female jaú, Zungaro jahu (Ihering, 1898) (Siluriformes: Pimelodidae), passed upstream of Funil Dam, rio Grande, Brazil. Neotrop Ichthyol 2007; 5:229-232. http://dx.doi.org/10.1590/S1679-62252007000200018
33. Jørgensen C, Enberg K, Dunlop ES, Arlinghaus R, Boukal DS, Brander K, et al. Ecology-Managing evolving fish stocks. Science 2007; 318(5854):1247-1248. http://dx.doi.org/10.1126/science.1148089
35. Heino M, Baulier L, Boukal DS, Ernande B, Johnston FD, Mollet FM et al. Can fisheries-induced evolution shift reference points for fisheries management? ICES J Mar Sci 2013; 70:707–721. http://dx.doi.org/10.1093/icesjms/fst077
37. Laugen AT, Engelhard GH, Whitlock R, Arlinghaus R, Dankel DJ, Dunlop ES et al. Evolutionary impact assessment: accounting for evolutionary consequences of fishing in an ecosystem approach to fisheries management. Fish Fish 2014; 15:65–96 http://dx.doi.org/10.1111/faf.12007
39. Venturelli PA, Shuter BJ, Murphy CA. Evidence for harvest-induced maternal influences on the reproductive rates of fish populations. Proc Biol Sci 2009; 276(1658):919-924 http://dx.doi.org/10.1098/rspb.2008.1507