Locust control in Madagascar – up to the last breath

Locust control in Madagascar – up to the last breath

04/05/2015

Late morning on Beravy Plain in Madagascar – the sky is clear, the air is heavy and the grass high and green although it starts drying out, with some sparse trees. An FAO team is carrying out an aerial survey, looking for hopper patches and bands, in an helicopter flying at low altitude.

 

From the helicopter, the vegetation seems to be dotted with brown spots that might be hopper groups. The helicopter lands, the engine is switched off. On foot, the FAO team heads towards the area where it thinks it may have seen hopper bands – this is exactly what they are.

On the ground, sandy soil and gentle breeze, the purposeful stride of the scouts rouses the movement of the hoppers into sometimes chaotic motion. The hoppers are of last instar and gregarious – in a few days they will fledge (passing from the last hopper instar to the adult stage). After this final moult, small locust groups that until now were separate will gather and form light flights or swarms (depending on the density and size) able of to fly over long distances, consuming more food than hoppers and reproducing after sexual maturation. Treating these hopper groups is, therefore, a matter of urgency.

The characteristics of the hopper bands (instar and phase status of hoppers, density, size of bands and inter-band distance) along with GPS coordinates are noted in order to plan a full coverage treatment (treatment against late instar hoppers and locust adults) over the next two days.

The FAO team returns and the helicopter takes off to visit an area that was treated two days ago in order to assess the effectiveness of the full cover treatment to control late instar hopper bands. The GPS coordinates entered by the pilot to carry out the treatment enable him to fly directly to the concerned area where the team makes its observations.

The habitat is similar to the one where the hopper bands were observed a bit earlier in the day. The ground is strewn with dead last instar gregarious hoppers, and here and there, a dying locust. Some hoppers have died and remained hanging from a blade of grass as if struck down while they were feeding. The control was effective, with a mortality rate above 95 percent.

Return to base camp, far from human activity. In the tent that serves as headquarters, the full FAO team gathers, discussing possible tactical adjustments and establishing the operation plan for the next few days while sharing a meal cooked with local products.

The hot day ends with a rainstorm, refreshing the plain.