Water turbidity–induced alterations in coloration and courtship behavior of male guppies ( Poecilia reticulata )

Abstract

Water turbidity deteriorates visibility and thereby may change the physiology and behavior of aquatic animals that rely on vision. In the guppy fish (Poecilia reticulata), a key element in the mating behavior and reproductive success of males is female mate choice, which is predominantly based on visual signals. Females choose attractive males based on body coloration, and males court females by displaying their coloration. Here, we demonstrate that guppy males exhibit morphological and behavioral adjustments in response to changes in the visual environment. Males reared in turbid water had more conspicuous coloration than males reared in clear water, with higher intensity of carotenoid-based and ultraviolet colors, but not a larger area of red spots on the body. However, they performed less courtship displays in turbid water than males reared in clear water performed in clear water. Thus, increased coloration in turbid-water males was not accompanied by increased effort to display it. Although our findings demonstrated developmental plasticity in mating-related traits, turbidity-induced alteration in coloration did not match behavior change as could be predicted by favoring male attractiveness.

A non-vocal alarm? Effects of wing trill playbacks on antipredator responses in the scaled dove

Abstract

Animals have evolved a variety of mechanisms to detect and avoid predation. The non-vocal sounds produced by some bird species during takeoff flights have been considered to function as an alarm call, because they may convey information about predation risk. Here, we experimentally investigated the effects of the non-vocal sound (wing trills) produced by the scaled dove (Columbina squammata) on antipredation behaviours of conspecifics. We evaluated the individual response to playbacks of the wing trill stimulus and compared it to the response to other two control stimuli (vocalizations of the scaled dove and the southern house wren). We found that doves’ probability to become vigilant or to display freezing behaviour was higher after a wing trills stimulus in comparison to the other playback stimuli. These results suggest that wing trill production in scaled doves communicate potential risks and are considered by the individuals in the decision-making process, but we cannot rule out the possibility that any takeoff flight sound might also promote antipredator responses.