Male harassment drives females to alter habitat use and leads to segregation of the sexes.

Sexual conflict is ubiquitous across taxa. It often results in male harassment of females for mating opportunities that are costly for females, in some cases reducing reproductive success and increasing mortality. One strategy that females may employ to avoid sexual harassment is to segregate spatially from males. In fact, we do find sexual segregation in habitat use in species that have high levels of sexual conflict; however, the role of sexual harassment in driving such segregation remains poorly understood. Here, we demonstrate experimentally in a population of wild Trinidadian guppies Poecilia reticulata that male sexual harassment drives females into habitats that they otherwise do not prefer to occupy. In support of the social factors hypothesis for sexual segregation, which states that social factors such as harassment drive sexual segregation, this female behaviour leads to segregation of the sexes. In the presence of males, females actively select areas of high predation risk, but low male presence, and thus trade off increased predation risk against reduced sexual harassment.

Environmental impact assessment - an important tool for decision makers

The use of Environmental Impact Assessment, EIA, as a tool for decision makers is described. EIA can be used for identifying, predicting and assessing impacts arising from proposed activities such as major development projects like industrial complexes, highways and water-related projects. Implementation of EIAs is usually for projects for which a number of alternatives may be assessed. The methods used at each stage of the EIA process are identified. The matrix method is used to illustrate an EIA of the development of an industrial complex, port and urban development. The alternatives of continuing with the traditional uses, that is, agriculture (sugar cane), fisheries and recreation are also assessed. Additionally, the impact of a third alternative of changing the monocrop agriculture to diversified agriculture is considered. It is recommended that EIAs are formally integrated into the planning process in Trinidad and Tobago. (AU)