Author(s)

Anna Leyrer¹, Edward Bush², James Geaghan³, Buffy Meyer⁴

¹St. Joseph’s Academy Baton Rouge, Louisiana, USA.
²Ag Center, Louisiana State University, Baton Rouge, LA, USA.
³Emeritus, Department of Experimental Statistics, Louisiana State University, Baton Rouge, LA, USA.
⁴Louisiana Department of Agriculture and Forestry, Baton Rouge, LA, USA.

Insects such as Acheta domesticus account for over half of marsh fish and migratory bird diet. Therefore, insects are very important to marsh and island ecosy stems and are susceptible to oil contamination, but little research has been done to study the effects of oil spills on cricket populations. The purpose of this experiment was to determine the effects of an oil spill event on Acheta domesticus mortality and hatch rate to establish environmental sustainability. The treatment groups included 0% oil contamination, 5% oil contamination and 10% oil contamination. The scientist counted the number of deaths in two-week, four-week, and six-week-old crickets after oil contamination. In addition, the scientist counted the number of hatchlings among treated cricket eggs. Error bar lines in the results section supported the scientist’s hypothesis that the crickets would be affected by oil contamination. In fact, over 90% of the 10% oil treatment group died and over 80% of the 5% oil treatment group died after five days of oil contamination in the six-week-old experiment. The scientist used a Gas Chromatography Mass Spectrometer to determine if benzene, toluene, ethylbenzene, or xylene (total) were present in the sediment samples. BTEX exposure is suspected to possibly cause insect mortality. These volatile organic compounds were present in the samples and were found in higher quantities in samples with higher concentrations of oil. The highest quantity of volatile organic compounds present was xylene. After studying the population dynamics of the tested Acheta domesticus, the scientist found that the two-week and four-week-old crickets’ survivability could fit a linear model while the six-week-old crickets fit an exponential model. The scientist used these models to observe how long it took each treatment group to approach zero, and the oiled groups grew closer to a population of zero significantly faster. For example, it took about twenty-seven days for the 10% treatment group’s population to approach zero whereas the control, 0% treatment group, took about seven days in the two-week-old cricket experiment. Overall, the six-week-old crickets had the highest mortality, and the cricket egg experiment resulted in extremely low hatch rate. Specifically, the highest number of crickets that hatched in an oiled replication either 5% or 10% oil was eight out of the five thousand eggs laid. Since the adult crickets are the most physically able to reproduce and the cricket eggs had low hatch rates, the cricket population would significantly decrease after an oil spill with 5% or more soil contamination. However, if the plant matter that crickets consume is still present in their environment, they may be able to recover.

Entomology, Contamination, Oil, Insects, Sustainability, Marsh

Leyrer, A. , Bush, E. , Geaghan, J. and Meyer, B. (2020) A Biological Restoration Model for Contaminated Coastal Marshes and Islands Using the Life Cycle of Acheta domesticus to Establish Environmental Sustainability. Computational Water, Energy, and Environmental Engineering, 9, 13-21. doi: 10.4236/cweee.2020.92002.