Abstract:

This dataset will explore the effects of oil exposure predator evasion ability. A dose response swim study, using a Loligo swim tunnel, was used to verify a dose in which swim performance was impaired. That dose was then used in a predator evasion assay. A group of 10 (~1 gram) red drum (Sciaenops ocellatus) were exposed for 24 hours. Following exposure, the group was placed into an arena with a sandy bottom and seagrass beds. Over a four-hour period, the location of each individual was recorded every 30 minutes. After this 4-hour period, three predators (~175 g Pinfish) were placed into the tank. Location of prey and predators, as well as prey survival, were recorded for three hours. Additionally, 16 fish (8- control and 8- 20% HEWAF) we placed in a standard dual-choice sociability assay.

Suggested Citation:

Khursigara, Alexis and Andrew Esbaugh. 2021. Oil exposure effects on predator evasion in red drum (Sciaenops ocellatus). Distributed by: GRIIDC, Harte Research Institute, Texas A&M University–Corpus Christi. doi:10.7266/E1Y6VSHZ

Purpose:

Investigate the role of oil exposure on predator fish evasion.

Data Parameters and Units:

Temperature - C, Salinity - ppt, Mass - g, Length - cm, Volume - ml or L, Time - HH:MM, Date - MM/DD/YY , metabolic rate- mgO2/kg/hr swim performance- body lengths/sec, Activity - s, Burst movement - s/cm, Acceleration - s/cm, Speed - s/cm, Distance Moved - cm, Time spent in Zone- s.

Methods:

Predator evasion: Groups of 10 red drum fish were exposed to control or oil for 24 hours. Following exposure, fish were placed in a large arena for four hours. Their location and group size was assessed every 30 minutes. After three hours, three predators (pinfish) were added to the tank. Survival, prey group size and location, and predator location were measured every five minutes for the first half hour and every 10 minutes until three hours. Swimming: Fish were individually exposed to control or varying levels of oil for 24 hours. Immediately after exposure, fish were placed into swim tunnels to acclimate overnight. The following morning, a swimming trial started to measure metabolic rate and swim performance. Sociability: Fish were individually exposed to control or 20% HEWAF for 24 hours. Immediately after exposure, fish were rinsed and placed into a dual choice sociability test. Fish were acclimated in the center arena for two minutes in a transparent acclimation chamber. After acclimation, fish were allowed to explore the center chamber for five minutes in an exploration assay. After five minutes, dividers on either side of the acclimation chamber were removed to reveal a social chamber (containing four familiar stimulus fish) and an asocial chamber (no fish). Focal fish were able to see but not interact with stimulus fish. Videos of the assay were used to measure a number of parameters using Lolitrack systems. HEWAFs were prepared by mixing 1 gram of OFS oil and 1 L filtered seawater (35 ppt) in an industrial blender for 30 seconds on low. HEWAFs were then transferred to a Teflon funnel where it sat for an hour. After this hour, the lower 85% was drained and this was designated as our 100% HEWAF. Oil exposures were generated using the 100% HEWAF and filtered seawater and mixing by percent volume.

Instruments:

Loligo swim tunnels with accompanying software, 260-gallon tank, sand, artificial seagrass, Lolitrack 5 and web-cameras

Error Analysis:

Swimming was compared using a One Way ANOVA. Predator Evasion was assessed using One and Two Way ANOVAs in addition to a regression for time to 50% mortality. Sociability all parameters were individually assessed using a t-test. Additionally all parameters were condensed into a single behavior score using a PCA and the PC1 scores were compared using a t-test.

Individual Files: