56

■Bio-mathematics, Statistics and Nano-Technologies: Mosquito Control Strategies

Figure 4.9: Gravid trap boxes used to collect adult mosquitos.

Pit shelters can be sampled every morning from 7:00 am to 7:30 am, the pit dimensions

were as described in entomology manual for collecting outdoor resting mosquito’s density

(Eliningaya & Aneth 2009). OBET, the trap is composed of a tent with either a man or

cow whose odors are drawn to a cage trap by a fan via polythene tunnel. OBET dimen-

sions were height 2 meters, length 2 meters and width 1.5 meters (Eliningaya & Aneth

2009). For HLC, the same man can expose his feet while using mechanical aspirator for

collecting landing mosquitos at each collection site, one collector worked from 6:00 p.m.

to 6:00 am, mosquitos were sorted by an hour interval. OBET used both man and cows:

the mosquitos seeking for hosts were collected in a protected chamber before reaching the

host (Eliningaya & Aneth 2009).

4.13.2

Gravid Trap Box

This trap looks like a tool box sitting on top of a tray. The tray contains a mixture

of fermented grass and straw which has a powerful smell (disagreeable to people) but

attractive to mosquitos. The tool box contains a collecting pod, and a small fan that is

powered by four “D” cell batteries (Figure 4.9). When the mosquitos are attracted to the

water to lay eggs, they pass by the trap opening and are pulled into the collection pod.

The mosquitos are removed in the laboratory for examination and analysis. These traps are

usually used when intending to collect Culex gravid female mosquitos.

4.13.3

The ovitraps

The ovitraps are a small water-containing vessel that looks like a stadium cup with a

surface inside it (such as a tongue depressor) for mosquitos to lay their eggs on (Figure

4.10 a). The surface containing the eggs are collected and counted to determine the density

of the reproductive mosquito population. These ovitraps will provide initial and ongoing

data on mosquito populations. Ovitraps are mainly used to collect Aedes albopictus eggs.

4.13.4

The Fay Prince trap

The Fay Prince trap is a daytime trap that is used to collect the Asian tiger mosquito,

Aedes albopicuts. These traps are suspended from low branches and trees and work much

like a CDC miniature light trap except it uses contrasting black and white surfaces to attract