The Sublethal Effects of Low-pH Exposure on the Chemoreception of Poecilia sphenops

In this study, Poecilia sphenops (gold mollies) were chronically exposed to low pH that mimic those found in natural environments, e.g., rivers and lakes. The Poecilia sphenops were placed in two separate aquaria with pH levels of 5 and 6 and presented with a different chemically mediated behavioral challenge of locating the food source. The results indicated that under pH 5 the Poecilia sphenops had difficulties in locating the odor source of food and at the same time their swimming speed were greatly reduced. The failure by the Poecilia sphenops to locate the food source and their reduced swimming speed can have a negative impact on the survival of the fish by introducing a high probability of starvation. If the fish are starved, it means that even their reproduction rate will be reduced, while the juveniles growth will be arrested under natural conditions of acidification. In addition to this, since the fish's swimming speed is also impaired, it means that, they will be unable to run away from their predators once found. The combination of starvation and failure to run away from predators could negatively impact the gold mollies severely. Their fitness would be compromised.