Life Sciences Commons^™

Survival-Larval Density Relationships In The Field And Their Implications For Control Of Container-Dwelling Aedes Mosquitoes, Katherine G. Evans, Zoey R. Neale, Brendan Holly, Cecilia C. Canizela, Steven A. Juliano

Faculty Publications – Biological Sciences

Population density can affect survival, growth, development time, and adult size and fecundity, which are collectively known as density-dependent effects. Container Aedes larvae often attain high densities in nature, and those densities may be reduced when larval control is applied. We tested the hypothesis that density-dependent effects on survival are common and strong in nature and could result in maximal adult production at intermediate densities for Aedes aegypti, Aedes albopictus, and Aedes triseriatus. We surveyed naturally occurring densities in field containers, then introduced larvae at a similar range of densities, and censused the containers for survivors. We analyzed the survival-density …

Overcompensation In Aedes Mosquitoes Populations: Field Tests On Likelihood And An Agent-Based Model To Investigate The Influence Of Cohort Structure, Katherine G. Evans

Theses and Dissertations

The number of individuals in a competitive environment can affect the growth rate, survival, size, and fecundity of those individuals, which is known as density-dependent effects. Overcompensation may occur if few juveniles survive to adulthood in a high-density environment. Overcompensation arises when density dependent survival interacts with extrinsic sources of mortality, such that more juveniles survive to adulthood than if no extrinsic mortality had occurred.

I tested the hypothesis that density dependent effects are common and strong in the field for three mosquito species: Aedes aegypti, Aedes albopictus, and Aedes triseriatus. I surveyed naturally occurring densities in novel and established …

Finding The Sweet Spot: What Levels Of Larval Mortality Lead To Compensation Or Overcompensation In Adult Production?, Zoey R. Neale, Steven A. Juliano

Faculty Publications – Biological Sciences

Extrinsic mortality impinging on negative density-dependent populations can result in no change in the number of survivors (compensation) or an increase (overcompensation) by releasing the population from density-dependent effects on survivorship. The relationship between the level of extrinsic mortality (i.e., percentage of mortality) and the level and likelihood of overcompensation is theoretically important, but rarely investigated. We tested the hypothesis that overcompensation occurs below a threshold value of extrinsic mortality that is related to density-dependent mortality rate and that additive extrinsic mortality occurs above this threshold. This hypothesis predicts that survivorship vs. extrinsic mortality will (1) be best described by …

When Does Less Equal More? Assessing The Mechanisms Driving Compensatory Mortality And The Hydra Effect, Joseph T. Neale

Theses and Dissertations

Many populations across taxa are regulated by negative density-dependence, wherein increased population sizes lead to decreased birth rates and/or increased mortality. By releasing such populations from some level of these density-dependent effects, extrinsic mortality can lead to counter-intuitive results, such as no change in population size (compensation), or an increase in population size (overcompensation). These results have been documented experimentally, but there currently exists a dearth of empirical studies exploring the mechanisms behind the phenomenon. We tested the relationship between extrinsic mortality level and (over)compensation in four mosquito species – Aedes aegypti, A. albopictus, A. triseriatus, and Culex pipiens – …