Why Do Mosquitoes Fly Low?
WouterDespite the importance of mosquitoes to the health of humans, little research has been conducted on their flight dynamics. This study is an attempt to gain insights into the flight behaviour of mosquitoes at different altitudes. The flight behaviour of mosquitoes in higher altitudes may have implications for the design of odour-baited traps.
Using a high-speed camera system, we filmed the vicinity of a BG-Suna trap. The trap was set in 8 m3 of space, and positioned at 35 cm from each wall. Using the Matlab image processing toolbox, we calculated two-dimensional positions of mosquitoes. Then, using the Hungarian linker algorithm, we reconstructed flight tracks by finding the minimum distance between detected positions in subsequent frames.
The flight behaviour of mosquitoes in standing and hanging traps was similar in that both had similar two-dimensional distributions of translational speeds. However, mosquitoes near standing traps had higher angular speeds and turn rates, and flew faster. They also flew towards the horizontal platform of the standing trap.
Mosquitoes near hanging traps also flew downwards, away from the trap. They concentrated near the bottom corner of the back wall. They had lower mean speeds at radial distances of 10-20 cm from the entry tube. They flew towards the axis of symmetry of the trap, but never remained there for long. They also had low positional likelihood.
Mosquitoes near odour-baited traps exhibited tortuous flight behaviour. They flew upwards towards the trap, and then flew downwards towards the ground.
