Oral Presentation Society of Environmental Toxicology and Chemistry Australasia 2023

Drugs in a social setting: How temazepam exposure affects the group formation and behaviour of unfamiliar fish (#104)

Jake M Martin 1 2 , Jack L Manera 3 , Kenny Olajide 1 , Mirjam Amcoff 2 , Alexander Kotrschal 4 , Alexander Szorkovszky 5 , Tomas Brodin 1 , Michael G Bertram 1 2 3 , Niclas Kolm 2
  1. Department of Wildlife, Fish, and Environmental Studies, Swedish University of Agricultural Sciences, Umeå, Sweden
  2. Department of Zoology, Stockholm University, Stockholm, Sweden
  3. School of Biological Sciences, Monash, Melbourne, VIC, Australia
  4. Behavioural Ecology, Wageningen University & Research, Wageningen, Netherlands
  5. RITMO Centre for Interdisciplinary Studies in Rhythm, Time and Motion, University of Oslo, Oslo, Norway

The increasing diversity and widespread distribution of pharmaceutical pollutants in aquatic ecosystems are a growing global concern. Although the concentrations of pharmaceutical pollutants found in the environment are generally below lethal levels, they often elicit behavioural changes that can have significant consequences on the survival and overall fitness of aquatic organisms. Benzodiazepines, a class of psychoactive pharmaceuticals, are of particular concern since they are specifically designed to alter mood and behaviour. Studies have found that fish exposed to benzodiazepines exhibit changes in boldness, activity levels, and foraging behaviour. However, the impact of pharmaceutical pollutants on group behaviours, such as sociability and movement dynamics within shoals, has largely been overlooked. This is despite the crucial role group behaviour plays for fish in improving foraging efficiency, predator avoidance, and finding mates. In this experiment, we aimed to investigate the impact of the benzodiazepine temazepam on group formation and behaviour in guppies (Poecilia reticulata). We used guppies from selection lines selected for increased sociability and decreased sociability, to investigate the consistency of temazepam's effects across individuals with different baseline group behaviour. The fish were exposed to one of three environmentally relevant concentrations of temazepam (0ng/L, 100ng/L, 1000ng/L). Following a 10-day exposure period, fish were placed in a circular arena with unfamiliar conspecifics from the same treatment. We recorded the behaviour of the group and tracked each individual to quantify alignment and cohesion as well as activity levels. Preliminary results indicate an interaction between exposure to temazepam and sociability of individuals. These findings not only underscore potential differential effects of pharmaceutical pollutants on distinct social groups, but also demonstrate ecological consequences, revealing their potential to disrupt the intricate social dynamics and behaviours of aquatic wildlife.