Abstract:

We monitored ant mortality in the lab when exposed to vapors of Macondo oil. The objective was to increase our understanding of ecological damages and recovery in the Spartina marshes. We investigated what effects exposure to the oil emulsion had on the foraging behavior and rate of mortality of acrobat ants, Crematogaster pilosa Emery (Hymenoptera: Formicidae). Ants have previously been used in a variety of disturbance-based ecological studies and thus may also provide important information on the health of the Louisiana salt marshes. The hypotheses tested were: The presence of DWH-associated crude oil will reduce the foraging behavior of Crematogaster pilosa; and the presence of DWH-associated crude oil will increase morality in Crematogaster pilosa. This dataset includes data on survival that can be used to calculate LD50 . Ants were exposed to one of 5 treatments, or a control. Food, water, and oil in the case of treatments were then a dded to each of the 5 replications. The number of ants in each replicate was no less than 20 and no more than 100 individuals. Ants were exposed to treatments for 24 hours. C. pilosa’s foraging behavior was drastically reduced by oil presence (p < 0.0001) though oil did not usually increase mortality.

Suggested Citation:

Linda Hooper-Bui. 2015. Crematogaster pilosa (Ant) Mortality Trials in the Lab when Exposed to Macondo Oil. Distributed by: GRIIDC, Harte Research Institute, Texas A&M University–Corpus Christi. doi:10.7266/N7C8276X

Purpose:

The dataset was developed to study the mortaltity of ants in the lab when exposed to vapors of Macondo oil.

Data Parameters and Units:

Treatments 1 = Replicates from corresponding sites 2-8 Mort Starv = Corresponds to the percentage of ants that died of starvation after 24 hour fasting period Treatments 2 =Replicates from corresponding sites 2-8 Mort Treat = Corresponds to the percentage of ants that died of starvation after food source was surrounded by oil Column E = corresponding sites 2-8 average = average mortality for all replicate trials for each corresponding site standard dev = standard deviation of the average percent mortality of 5 replicates in the same treatment std error. = standard error of the average percent mortality of 5 replicates in the same treatment

Methods:

A treatment was composed of one cohort of ants, food/water or a food/water dummy, and oil. The controls included one cohort of ants and food/water or a food/water dummy. Food and water consisted of one culture tube with 20% sugar water solution and one piece of Fluker’s Cricket Quencher abou t 1cm3. Each trial of the experiment consisted of a treatment or control with five replications. For each trial, five cohorts of ants were selected from five different colonies. Cohorts consisted of no less than 20 and no more than 100 individuals. After this period of starvation and dehydration, any dead ants were counted and removed from the arena then stored in 95% ethanol solution for later analysis. Food, water, and oil in the case of treatments were then added to each of the 5 replications. When applied, Oil was painted onto the bottom of the plastic dish in a 1cm thick ring using an artist’s paint brush.

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