Linking Oviposition Site Choice to Offspring Fitness in Aedes aegypti: Consequences for Targeted Larval Control of Dengue Vectors

Abstract

BackgroundCurrent Aedes aegypti larval control methods are often insufficient for preventing dengue epidemics. To improve control efficiency and cost-effectiveness, some advocate eliminating or treating only highly productive containers. The population-level outcome of this strategy, however, will depend on details of Ae. aegypti oviposition behavior.Methodology/Principal FindingsWe simultaneously monitored female oviposition and juvenile development in 80 experimental containers located across 20 houses in Iquitos, Peru, to test the hypothesis that Ae. aegypti oviposit preferentially in sites with the greatest potential for maximizing offspring fitness. Females consistently laid more eggs in large vs. small containers (β = 9.18, p<0.001), and in unmanaged vs. manually filled containers (β = 5.33, p<0.001). Using microsatellites to track the development of immature Ae. aegypti, we found a negative correlation between oviposition preference and pupation probability (β = −3.37, p<0.001). Body size of emerging adults was also negatively associated with the preferred oviposition site characteristics of large size (females: β = −0.19, p<0.001; males: β = −0.11, p = 0.002) and non-management (females: β = −0.17, p<0.001; males: β = −0.11, p<0.001). Inside a semi-field enclosure, we simulated a container elimination campaign targeting the most productive oviposition sites. Compared to the two post-intervention trials, egg batches were more clumped during the first pre-intervention trial (β = −0.17, P<0.001), but not the second (β = 0.01, p = 0.900). Overall, when preferred containers were unavailable, the probability that any given container received eggs increased (β = 1.36, p<0.001).Conclusions/Significance Ae. aegypti oviposition site choice can contribute to population regulation by limiting the production and size of adults. Targeted larval control strategies may unintentionally lead to dispersion of eggs among suitable, but previously unoccupied or under-utilized containers. We recommend integrating targeted larval control measures with other strategies that leverage selective oviposition behavior, such as luring ovipositing females to gravid traps or egg sinks.

Hot temperatures can force delayed mosquito outbreaks via sequential changes in Aedes aegypti demographic parameters in autocorrelated environments

“…We also assumed the transition from normal to "hot" environments could further decrease survival (p 3 < p 2 ) based on observations from experiments were Ae aegypti larval mortality increased and then decreased following environmental disturbances (Agudelo-Silva & Spielman 1984; Wilson et al 1990). Using the estimate for the product of larval survival and fecundity ( , Table S1) we were able to estimate the fecundity for normal ( 3.42) and "hot" ( 6.84) environments under the assumption of a fecundity-survival trade-off (Stearns 2000), which is plausible assumption for Ae aegypti (Wong et al 2012). The fecunditysurvival trade-off assumes the product of fecundity and larval survival to be constant ( ).…”

Attracted to the enemy: Aedes aegypti prefers oviposition sites with predator-killed conspecifics

“…They exhibit complex oviposition choices depending on, conspecific density (Suleman and Shirin 1981; McCrae 1984; Laurence and Pickett 1985; Reiskind and Wilson 2004), predators (Chesson 1984; Blaustein et al 2005) and detritus amount (Edgerly et al 1998; Wong et al 2011, 2012), within oviposition sites (Yee and Juliano 2006, Yee et al 2007a). Several species demonstrate strong oviposition preferences, for sites where the bacteria upon which larvae feed are abundant (Walker et al 1991; Allan and Kline 1995; Navarro et al 2003; Trexler et al 2003; Ponnusamy et al 2010) a preference often mediated via chemical cues (Hazard et al 1967; Allan and Kline 1995; Sant’ana et al 2006; Ponnusamy et al 2010).…”

Oviposition Site Selection Structures Niche Partitioning Among Coccinellid Species in a Tropical Ecosystem

“…Many studies have shown that biotic factors influence the behavior of invertebrate females when choosing where to lay their eggs (Craig et al 1989, Machado & Oliveira 2002, Wong et al 2012. For breeding lady beetle females, resource availability (i.e., aphid presence on the plants) is an important cue to stimulate oviposition (Evans & Dixon 1986, Seagraves 2009).…”