This paper elucidates the phytoremediation potential of water hyacinth and water lettuce on the reduction of wastewater toxicity. Acute toxicity tests were performed in an aquarium with a population of Sarotherodon melanotheron, contaminated by different concentrations of wastewaters before and after phytoremediation with Eichhornia crassipes and Pistia stratiotes. Lethal concentrations (LC50) of the fish's population obtained during 24 hours of exposures were determined. COD, BOD, ammonium, TKN and PO4(3-) concentrations in wastewaters were of 1850.29, 973.33, 38.34, 61.49 and 39.23 mg L(-1), respectively, for each plant. Phytoremediation reduced 58.87% of ammonium content, 50.04% of PO4(3-), 82.45% of COD and 84.91% of BOD. After 15 days of the experiment, metal contents in treated wastewaters decreased from 6.65 to 97.56% for water hyacinth and 3.51 to 93.51% for water lettuce tanks. Toxicity tests showed that the mortality of fish exposed increased with increase in concentration of pollutants in wastewaters and the time of exposure. Therefore, the highest value of LC50 was recorded for fish subjected to 3 hours of exposure (16.37%). The lowest rate was obtained after an exposure of 20 to 24 hours (5.85%). After phytoremediation, the effluents purified by Eichhornia crassipes can maintain the fish life beyond 24 hours of exposure.

Aims: The study carried out aimed to evaluate the modes of exploitation of edible frogs. Place and Duration of Study: The present study was performed during the month of January to February 2022. The survey was conducted in the villages of Kassiapleu, Kouitongouiné and Gbangbégouiné. These villages are located in MAN (West of Côte d’Ivoire). Methodology: Surveys have been carried out among actors exploiting this animal resource. The study involved 210 consumers and 15 frog harvesters in the locality of MAN. A well-structured questionnaire provided data on fishing techniques and frog consumption patterns. Results: This study reveals that there are two main fishing methods: arrow fishing (57.1%) and hook and line fishing (42.9%). The catches are made in different humid ecological zones and the exploitation is only intended for local consumption. The smoked form is the most popular with consumers (59.5%). The majority of respondents consume this meat because of the taste (83.3%) compared to that of chicken (44.8%) and fish (31.4%). Conclusion: In view of these results obtained, the establishment of a rational exploitation strategy must be considered for the conservation of edible frog species.

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