Abstract
BackgroundField ecologists often rely on mark-release-recapture (MRR) experiments to estimate population dynamics parameters for a given species. In the case of a medically important taxon, i.e., a disease vector, inferences on species survival and dispersal rates are particularly important as they have the potential to provide insights into disease transmission dynamics in endemic areas. Medical entomologists have traditionally used fluorescent dusts to externally mark the cuticle of insects. However, dust marking is usually restricted to the adult life stage because immature insects lose the mark when they molt.Methodology/Principal FindingsWe evaluated the efficacy of 13 trace elements in marking nymphs of three native Brazilian Chagas disease vectors: Triatoma brasiliensis, Triatoma pseudomaculata, and Rhodnius nasutus. Cr and Cu were detected in over 97% of T. brasiliensis (34/35 31/31 for Cr and Cu), while Cu and Mn were detected in more than 95% of T. pseudomaculata (29/29 for Cu and 28/29 for Mn) tested 120 days after marking. Only Mn marked over 90% of R. nasutus nymphs (38/41). Overall, trace elements had no negative effects on T. pseudomaculata longevity, but As-marked T. brasiliensis nymphs (p<0.01), and Cd-marked R. nasutus nymphs (p<0.01) had significantly shorter lifespan.Conclusions/SignificancePrevious evidence shows that there is little or no genetic differentiation between populations at the microgeographic level, which often precludes indirect estimations of dispersal capability based on genetic markers. In such situations, MRR studies are more suitable as they measure insect movement directly from one site to another, instead of effective migration (i.e. gene flow). The determination of a reliable and persistent marking method is the first step towards the development of meaningful ecological estimates through the application of MRR methodology. Here, we have identified trace elements that can be used for mark and recapture studies of three triatomine species in Brazil.
Highlights
Mark-release-recapture (MRR) is an important method used to estimate several ecological parameters of natural populations
We evaluated the persistence and efficiency of trace elements, chemicals present in very low quantities in the organism of a targeted species, to mark the nymphs of three Chagas disease vectors of the Brazilian caatinga biome, Triatoma brasiliensis, T. pseudomaculata, and Rhodnius nasutus
At least one trace element was shown to be a good marker for each triatomine species: more than 97% of T. brasiliensis were still marked with Cr and Cu after 120 days; more than 95% of T. pseudomaculata were marked with Cu and Mn and more than 90% of R. nasutus were marked with Mn 120 days after marking
Summary
Mark-release-recapture (MRR) is an important method used to estimate several ecological parameters of natural populations. Species survival, dispersal rates and population density might be inferred based on the collection of previously marked and released individuals. A subset of a given population is captured, marked, and released. On the subsequent collection effort, another subset is captured and the number of marked (and unmarked) individuals within the same sample is recorded. Field ecologists often rely on mark-release-recapture (MRR) experiments to estimate population dynamics parameters for a given species. In the case of a medically important taxon, i.e., a disease vector, inferences on species survival and dispersal rates are important as they have the potential to provide insights into disease transmission dynamics in endemic areas. Medical entomologists have traditionally used fluorescent dusts to externally mark the cuticle of insects. Dust marking is usually restricted to the adult life stage because immature insects lose the mark when they molt.
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
