Habitat alteration influences male signalling effort in the Australian desert goby

Abstract

Male sexual signals provide vital information about the quality of the signaller and can have important consequences for male repro -ductive success. Habitat changes, however, are expected to affect male sexual displays. An important question, therefore, is to deter -mine if and how such sexual displays are adjusted to changes in the signalling environment, especially in highly dynamic syst ems or those affected by human-induced environmental change. Desert, rivers, and springs are among the worldOs most threatened habitats. Many of these fragile water bodies are being overwhelmed by invasive weeds and excess primary productivity as an indirect res ult of human agricultural demand for freshwater. Here, we investigated the effects of altered habitat on the courtship effort of male des -ert gobies, Chlamydogobius eremius. Male courtship effort was observed in an environment that was either dominated by bulrush (Typha sp. ) or modiÞed by increased algal turbidity ( Scendesmus sp. ). We found that males that were exposed to an environment domi -nated by bulrush spent more time courting in these environments compared with environments that were unaltered. In contrast, males that were exposed to environments modiÞed by increased algal turbidity not only took longer to initiate courtship but also s pent less time courting females. These results suggest that different habitat alterations can have important consequences for the repr oductive behavior of affected organisms and, ultimately, the direction of sexual selection.