Evaluation of a Stable Isotope Method to Mark Naturally-Breeding Larval Mosquitoes for Adult Dispersal Studies

Abstract

Understanding mosquito dispersal is critically important for vector-borne disease control and prevention. Mark–release–recapture methods using various marking techniques have made substantial contributions to the study of mosquito biology. However, the ability to mark naturally breeding mosquitoes noninvasively and with life-long retention has remained problematic. Here, we describe a method to mark naturally breeding mosquitoes with stable isotopes. Culexpipiens f. molestus mosquitoes were provisioned as larvae in laboratory experiments with 15N-labeled potassium nitrate and 13C-labeled glucose. Larval enrichment was sufficient to differentiate marked adult mosquitoes from unmarked control mosquitoes and the natural source population from Chicago Illinois, using either δ15N or δ13C. Isotopic retention lasted for at least 55 d for adult male and females mosquitoes. There were no consistent effects of isotopic enrichment on immature mosquito survival or adult mosquito body size. We then applied this marking technique to naturally breeding Culex pipiens mosquitoes in suburban Chicago, IL, and for the first time, report successful isotopic enrichment of mosquitoes in the field. This stable isotope marking technique will facilitate studies of mosquito dispersal.

Dispersal of Adult Culex Mosquitoes in an Urban West Nile Virus Hotspot: A Mark-Capture Study Incorporating Stable Isotope Enrichment of Natural Larval Habitats

“…The ability to mark wild mosquitoes in natural containers with a non-invasive marker is an ideal approach to avoid artifacts of the marker or unnatural larval diet that may influence dispersal behavior [1], [12]. Additionally, our previous laboratory experiment revealed low decay rates of 15 N in mosquitoes held for 55 days post-emergence [17]. Based on the enrichment achieved in the field during the current study, the stable isotope marker should offer sufficient retention for the life of the mosquito, which is fortunate given the significance of old females for disease transmission.…”

Landscape Movements of Anopheles gambiae Malaria Vector Mosquitoes in Rural Gambia

“…Spatially explicit, coupled larval and adult mosquito field surveys, combined with high resolution mapping of habitats, can be designed to test theoretical movement models. There is also considerable potential in the use of isotopes in MRR experiments [26], following the recent successful application of this technique to water bodies, thereby marking naturally-breeding mosquitoes at known sources [62].…”

Radiation Biology and Inherited Sterility of Light Brown Apple Moth (Lepidoptera: Tortricidae): Developing a Sterile Insect Release Program

“…However, despite progress made in the last decade, there is still a lack of adequate tools and methods to assess performance of sterile insects in comparison with wild insects (Dyck et al 2005;Simmons et al 2010) making the completion of the essential quality evaluation loop challenging. Stable isotope tools offer an opportunity to contribute to the completion of the quality control loop, as they allow us to study the essential biology and ecology of insects , including the distribution and movement of populations across the landscape, and estimation of population size (Hood-Nowotny & Knols 2007)-all of which are factors critical in an insect control program (Hamer et al 2012). Stable isotopes are non-radioactive and ubiquitous; for example 13 C with its 1 extra neutron constitutes 1 percent of all C atoms globally, posing no threat to public or environmental safety.…”

“…Isotope markers have proved to be a suitable population marker for mosquitoes (Hood-Nowotny et al 2006;Hamer et al 2012), fruit flies (Hood-Nowotny et al 2009), and tsetse flies (Hood-Nowotny et al 2011). In this paper, we set out to determine whether stable isotope signatures could also be used as secondary independent markers in lepidopteran species, based on the natural signature differences between wild host plants and laboratory artificial diets.…”