A comparison of egg desiccation tolerance and development under different temperatures for three common Aedes mosquitoes
Date of Award
Honors College Thesis
Donald Yee, Ph.D.
With the rise in global temperatures, invasive mosquito species like Aedes albopictus may be able to reach regions that were previously inhospitable to these species. Therefore, if A. albopictus were to potentially reach Puerto Rico, it would come into contact with the species of Aedes aegypti and Aedes mediovittatus in local containers, and it is unclear how the tropical temperatures and precipitation patterns would affect the co-occurrence of these three species. Egg desiccation and temperature dependent growth among the species were measured to test how these species hatched and developed during different humidity and temperature. It was hypothesized that there would be variable desiccation and growth among the different species of Aedes, with A. albopictus faring better at higher temperatures and a higher degree of humidity and A. aegypti faring better at lower temperatures and a lower degree of humidity. The experiment was split into two parts: 1) egg desiccation, where eggs were placed in envelopes in incubators set to three different percentages of humidity (25%, 50%, and 80%) and left for two or four weeks before being induced to hatch and emerged larvae from hatching being counted; and 2) temperature, where newly hatchedfirst instar larvae from a different treatment were placed in incubators of varying temperatures (20 ºC, 30 ºC, and 40 ºC) and checked daily for growth until the adult phase, at which point they were frozen, thawed, and weighed. The temperature data showed that development was fastest for all species at the highest temperatures but much slower at the lowest temperatures, with A. mediovittatus having the lowest survivability at 40 ºC. The humidity data showed that egg mortality was approximately equivalent among A. aegypti and A. albopictus (higher mortality at lower humidity and lower mortality at higher temperature), with A. mediovittatus progressing in the opposite direction of mortality. This part of the experiment was not completed due to the onset of COVID-19 causing a campus lockdown during data collection. It was concluded that, if A. albopictus were to invade Puerto Rico, it could exist alongside A. aegypti and A. mediovittatus due to Puerto Rico’s relatively warm temperatures and high humidity contributing to low egg mortality and fast development times among A. albopictus.
Copyright for this thesis is owned by the author. It may be freely accessed by all users. However, any reuse or reproduction not covered by the exceptions of the Fair Use or Educational Use clauses of U.S. Copyright Law or without permission of the copyright holder may be a violation of federal law. Contact the administrator if you have additional questions.
Hosch, Shelby A., "A comparison of egg desiccation tolerance and development under different temperatures for three common Aedes mosquitoes" (2020). Honors Theses. 719.