Article
Effects of an anthropic barrier concerning upstream migration of the amphidromous shrimp macrobrachium tenellum (Smith 1871) (Decapoda: Palaemonidae) in the Mexican Pacific coast [Efectos de una barrera antrZapotitlánpica sobre la migración río arriba del langostino anfZapotitlándromo macrobrachium tenellum (Smith 1871) (Decapoda: Palaemonidae) en la costa del Pacífico Mexicano]
Fecha
2014Autor
Rodriguez-Uribe, M.-C.
Vega-Villasante, F.
Guzman-Arroyo, M.
Espinosa-Chaurand, L.-D.
Institución
Resumen
We evaluated the upstream migratory behavior of juvenile Macrobrachium tenellum in the discharge fl oodgate of an artificial pond through sampling from September through December of 2012 at 7, 14 and 21 hours (n=39) and on a cycle of 24 h (n=10). The migratory phenomenon is preponderantly at night because: a) the greatest amount of juveniles migrating is at 0 h (6666 organism (org)/m2), whereas the lowest is at 14 h (247 org/m2); the maximum abundance of juveniles passing to the pond to continue with the migration is at 2:30 h (2700 org/h) and the minimum is from 14 to 17 h (org/h); of those which deviate and die, due to passing to the surrounding areas, the greatest abundance is at 22:30 h (4140 org/h) and the lowest at 14 h (1 org/h) and b) there are significant differences between the abundances of juveniles migrating in the three schedules, with the higher at 21 h and the lower at 14 h (one-way ANOVA). There are significant differences between the four months of observation in the three schedules; October is the month of highest abundances in the three schedules (two-way ANOVA). There exists a negative correlation of the abundance of migrating juveniles with the luminosity; correlation is suggested with the stream velocity, temperature and environmental humidity, while there is no correlation with temperature, pH, turbidity, salinity and oxygen concentration in the water. The ascent by the walls generates physical stress on the organisms as evidenced by a higher concentration of glucose (3,23 mg/ml). These results suggest that the existence of this barrier has negative implications on the upstream migration of this species.