PM15 Biomarkers
Exhibit Hall
8:00 AM - Monday
(PM248) Predator avoidance response in individual and groups of killifish: A novel tool for behavioral toxicology.
Kane, Andrew1, Salierno, James1, McGlone, Patrick1, 1 University of Maryland College Park, College Park, Maryland, USA
ABSTRACT- Behavioral toxicology provides integrated, whole-organism responses to environmentally-relevant concentrations of contaminants or stressors. Fish are excellent sentinels of environmental exposure to a variety of contaminants, however there is a paucity of ecologically-relevant endpoints to quantify behavioral alterations in response to stress exposure. This project focused on the development of a predator avoidance response of killifish, Fundulus heteroclitus. Using a dedicated, video-based computer tracking and analysis system, we examined responses of killifish, as individuals and as groups (5 per group), to overhead bird silhouettes as they flew above experimental exposure arenas. There was a significant (p<0.05) and remarkable response of 95.6 percent of the fish to the bird fly-by. This response consisted of immediate cessation of movement, lasting for 12.4 (+ 0.9) seconds for individual fish and 8.2 (+ 0.3) seconds for groups of fish. Velocity and percent movement endpoints significantly decreased in both individuals and groups after the visual threat was presented. Groups of fish displayed significant decreases in shoal velocity, nearest neighbor distance, and percent shoaling, with significant increases in percent aggregation. Groups of fish tended to slow down and become less organized (shift from shoaling to aggregating, with less interaction). However, when fish were actively shoaling, they was a tendency for increased polarization. Data from these pilot studies suggests that visually-cued predation avoidance is a discernable and quantifiable behavior in killifish. Stress-associated changes in predator avoidance, in addition to changes in other movement endpoints, represent quantifiable, ecologically-relevant alterations that may help to bridge the gap between laboratory studies and field exposure scenarios. Further, subtle but quantifiable behavioral endpoints provide scientists with a better understanding of the consequences of low-level contaminant and stress exposures on fish and other aquatic organisms. This research was supported in part by an EcoHAB grant (#R828224-010) from the USEPA Science to Achieve Results (STAR) Program.
Key words: Behavior, Fish, Predator avoidance, Fundulus heteroclitus