Atrazine exposure shifts activity but has minimal effects on courtship in an agrobiont spider

Abstract

The behavior of many animals relies upon the input of chemical signals throughout the environment. Those animals that live in close proximity to humans may then be at risk, as the input of anthropogenic chemicals can have significant sublethal effects by masking or altering these naturally occurring signals. While the herbicide atrazine has been found to have the potential to alter such chemical information, research is lacking on how it may impact agrobiont arthropods which are the first and most direct line of exposure. Here we investigated the sublethal effects atrazine may be playing on an agrobiont wolf spider that makes up a major component of agricultural spider communities in the Eastern United States. We exposed spiders to ecologically relevant doses of atrazine and monitored general activity patterns as well as mating behaviors. We found that while sex determined a large portion of activity variation in these predators, both males and females spent more time mobile but at lower speeds in the presence of atrazine. We did not find any evidence for info-disruption based on male courtship rate and mating success, but with increasing dosage of atrazine came shortened bouts of courtship leading to copulation. These results suggest that atrazine changed activity patterns of a wolf spider, which may result in altered foraging, survival, and reproduction.

Keywords: Beneficial arthropods; Pardosa; Pesticide; Sublethal.