Salinity Tolerance of Dormitator lebretonis (Pisces: Eleotridae: Steindachner, 1870) Reared in Water Tanks: Implications for Coastal Wetlands and Swamp Valorizations

Abstract

Dormitator lebretonis (Eleotridae: Steindachner, 1870) is a fish species that inhabits West African coastal environments from Senegal to Angola where this squeaker appears to be an important component of the artisanal fisheries. In particular, this eleotrid is widespread in Benin coastal waters including wetlands, and is intensively exploited for food. The current rearing experiment aimed to determine the salinity levels that favor the survival and growth factors of this squeaker. Six (6) treatments corresponding to six (6) salinity levels (0‰, 5‰, 10‰, 15‰, 20‰, 25‰) and three replicates with 15 individuals of D. lebretonis per replicate were considered for the experiment. Appropriate salinity levels were obtained from a mixture of sea water and fresh water. Overall, within each six (6) treatments, physicochemical features showed insignificant (P>0.05) variations. Regardless of rearing water salinity (0‰ - 25‰), D. lebretonis displayed high survivals ranging between 86.66% (salinity: 0‰) and 100% (salinity: 5‰ - 20‰). Percent weight gained (PWG: 7.94±0.01% - 14.39±0.02%) were moderate and significantly (P<0.05) varied with treatments. Also, significant (P<0.05) variations in the condition factors (K) were recorded, with means ranging between 1.68±0.04 and 1.92±0.01. Nevertheless, specific growth rates (SGR) did not show any significant (F5,18=0.328; P=0.890) variations across treatments. These findings could serve as reference data for an extensive aquacultural valorization of D. lebretonis in numerous Benin coastal wetlands and swamps.