Evaluation of the impact of wastewater from shrimp culture through forced exposure tests: guppy allevines (Poecilia reticulata) as bioindicator.

Investigation article

Abstract

The shrimp activity is of great importance for foreign trade, which is why it has increased in Ecuador in recent years, shrimp ponds are built on mangrove soils and wetlands, these ecosystems that are of ecological importance to the country and that are being affected by the growth of this activity. For this reason, this work proposes the use of ecotoxicological tests of forced exposure to evaluate the effect of wastewater from shrimp culture using Guppy fingerlings (Poecilia reticulata). A forced exposure trial was conducted to evaluate the potential contamination of the shrimp's wastewater. A sample of wastewater from a shrimp farm located in the La Segua Wetland was diluted with drum water to obtain 4 exposure treatments (25%, 50%, 75 and 100% residual water), plus a control (0% residual water). Fish tanks of 12x12x12 cm were used to carry out the test. In each tank, 6 Guppy fingerlings with an average size of 2.72 ± 0.2 cm were placed. The trial lasted 5 days, and each treatment was tested in triplicate. Every day of the trial a record of responses was taken, such as swimming capacity and mortality. The results show that the species P. reticulata did not show mortality or loss of swimming capacity during the test. In addition, an unforced exposure test was carried out to evaluate the sensitivity of the species during its exposure to the shrimp's residual water, demonstrating that this species showed a leakage response from the first hour of exposure in all the treatments exposition.

Keywords: Shrimp farm, wetland, wastewater.