Semi-field and indoor setups to study malaria mosquito swarming behavior

Niang, A., Nignan, C., Poda, B. S., Sawadogo, S. P., Dabiré, K. R., Gnankiné, O., Tripet, F., Roux, O. and Diabaté, A. (2019) Semi-field and indoor setups to study malaria mosquito swarming behavior. Parasites and Vectors, 12, 446. (doi: 10.1186/s13071-019-3688-0) (PMID:31506104) (PMCID:PMC6737701)

Abstract

Background: The recent resurgence of interest in sterile insect techniques to control vector mosquitoes has renewed interest in novel methods for observing mating behavior. Malarial vectors of the Anopheles gambiae complex are known to mate in swarms at specific locations at dawn and dusk. Most knowledge of mosquito swarming behavior is derived from field observations and a few experimental studies designed to assess critical parameters that affect mosquito swarming. However, such studies are difficult to implement in the field because of uncontrollable environmental factors and mosquito conditions. Here, we present two experimental setups specifically designed to analyze mosquito swarming behavior and provide evidence that swarming behavior of mosquitoes can be generated and accurately assessed under both semi-field and laboratory conditions. Methods: The Mosquito Ecology Research Facility setup is a semi-field enclosure made of 12 compartments (10.0 × 6.0 × 4.5 m L × W × H each) exposed to ambient meteorological and lighting conditions. The laboratory setup consists of a windowless room (5.1 × 4.7 × 3.0 m) in which both environmental and mosquito conditions can be controlled. In the two setups, 300 3–6-days-old An. coluzzii virgin males were released and some swarm characteristics were recorded such as the time at which the swarm started, the number of mosquitoes in the swarm and the height. Climatic conditions in the semi-field setup were also recorded. Results: In both setups, An. coluzzii males displayed stereotyped and consistent swarming behavior day after day; males gradually gather into a swarm over a ground marker at sunset, flying in loops in relation to specific visual features on the ground. Although semi-field climatic conditions were slightly different from outdoors conditions, they did not impede swarming behavior and swarm characteristics were similar to those observed in the field. Conclusions: Swarm characteristics and their consistency across days provide evidences that these facilities can be used confidently to study swarming behavior. These facilities come to complement existing semi-field setups and pave the way for new experimental studies which will enhance our understanding of mating behavior but also mosquito ecology and evolution, a prerequisite for application of genetic approaches to malaria control.

• Item Type: Articles
• Additional Information: This work was funded by a joint UK Medical Research Council (MRC) and the UK Department for International Development (DFID) Africa Research Leader grant to AD and FT (#97014) and by the ANR grant ANOFEEL (ANR-15-CE35-0001-01) to OR. BSP received financial support through a doctoral fellowship from IRD. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Niang, Dr Abdoulaye
• Authors: Niang, A., Nignan, C., Poda, B. S., Sawadogo, S. P., Dabiré, K. R., Gnankiné, O., Tripet, F., Roux, O., and Diabaté, A.
• College/School: College of Medical Veterinary and Life Sciences > School of Biodiversity, One Health & Veterinary Medicine
• Journal Name: Parasites and Vectors
• Publisher: BioMed Central
• ISSN: 1756-3305
• ISSN (Online): 1756-3305
• Copyright Holders: Copyright © 2019 The Authors
• First Published: First published in Parasites and Vectors 12: 446
• Publisher Policy: Reproduced under a Creative Commons License