Prozac in the water: Chronic fluoxetine exposure and predation risk interact to shape behaviors in an estuarine crab

Abstract

Predators exert considerable top‐down pressure on ecosystems by directly consuming prey or indirectly influencing their foraging behaviors and habitat use. Prey is, therefore, forced to balance predation risk with resource reward. A growing list of anthropogenic stressors such as rising temperatures and ocean acidification has been shown to influence prey risk behaviors and subsequently alter important ecosystem processes. Yet, limited attention has been paid to the effects of chronic pharmaceutical exposure on risk behavior or as an ecological stressor, despite widespread detection and persistence of these contaminants in aquatic environments. In the laboratory, we simulated estuarine conditions of the shore crab, Hemigrapsus oregonensis, and investigated whether chronic exposure (60 days) to field‐detected concentrations (0, 3, and 30 ng/L) of the antidepressant fluoxetine affected diurnal and nocturnal risk behaviors in the presence of a predator, Cancer productus. We found that exposure to fluoxetine influenced both diurnal and nocturnal prey risk behaviors by increasing foraging and locomotor activity in the presence of predators, particularly during the day when these crabs normally stay hidden. Crabs exposed to fluoxetine were also more aggressive, with a higher frequency of agonistic interactions and increased mortality due to conflicts with conspecifics. These results suggest that exposure to field‐detected concentrations of fluoxetine may alter the trade‐off between resource acquisition and predation risk among crabs in estuaries. This fills an important data gap, highlighting how intra‐ and interspecific behaviors are altered by exposure to field concentrations of pharmaceuticals; such data more explicitly identify potential ecological impacts of emerging contaminants on aquatic ecosystems and can aid water quality management.

Antipredator phenotype in crucian carp altered by a psychoactive drug

“…However, boldness in crucian carp was only affected by High FLX and not by Low FLX, the concentration that fish may encounter in the wild. This is in contrast to earlier studies where, for example, crabs reared in presence of a predator showed an increase in foraging and activity along with a more aggressive personality style when exposed to environmentally relevant concentrations of FLX (Peters et al., 2017). However, bioaccumulation of FLX differs between taxa (Boström et al., 2017; Lagesson et al., 2016) and drug targets and affinity may also vary, making the read‐across hypothesis less applicable outside its intended domain.…”

Field-realistic antidepressant exposure disrupts group foraging dynamics in mosquitofish

“…The primary target molecule of fluoxetine (the serotonin transport molecule) is conserved across all vertebrate taxa [7], and, thus, fluoxetine has the potential to affect a diverse array of ecologically important behaviours in wildlife [8,9]. Indeed, there is growing evidence that antidepressants, such as fluoxetine, can disrupt a range of behaviours in non-target species at environmentally relevant concentrations, such as activity [10][11][12][13], anxiety [14][15][16], predator avoidance and escape [17][18][19][20], and foraging [21,22]. However, to date, few studies have considered how impacts of psychoactive pollutants might be affected by social context [23,24], and fewer still have directly asked whether impacts seen in social isolation are reflective of those in a social context [25].…”

Drug Disposal: Knowledge and Practice Among Pharmacy Students in Brazil

“…The use of medicines may result in leftovers, and the absence of information from the population about how to proceed with these pharmaceutical products wastes can cause risks to the environment and human been (4)(5)(6). Many drugs have compounds with high potential for bioaccumulation and low biodegradability, and when deposited in the environment, can contaminate soil and water and cause effects on aquatic animals (6)(7)(8).…”

“…Some classes of drugs present greater relevance for environmental contamination by interfering directly in living systems, such as antibiotics and endocrine disruptors (6)(7)(8)(9). Aditya and Rattan (2014) and Pinto and cols (2014) showed a predominance in the inadequate disposal of antibiotics, and the bacterial resistance is the major concern regarding the disposal of this pharmacological class (10,11).…”