Desert Locust Bulletin 432 (September 2014) [EN/AR]
General Situation during September 2014
Forecast until mid-November 2014
The Desert Locust situation remained calm during September. Only low numbers of hoppers and adults were seen during surveys in the northern Sahel between Mauritania and Eritrea. However, ecological conditions remained very favourable for breeding and there may be more locusts present than seen during the surveys. This should become evident once vegetation dries out and adults form groups. Consequently, there is a risk for groups to form in western Mauritania, northern Mali and Niger, northeast Chad, central and eastern Sudan, and in western Eritrea. It appears that this has already started in eastern Sudan where adult groups and a swarm formed. Strict vigilance is required in all countries during October as there is a potential for the situation to deteriorate. Good rains fell in the winter breeding areas along the eastern side of the Red Sea where small-scale breeding will cause locust numbers to increase. The situation remains unclear in Yemen due to insecurity. Elsewhere, a few small swarms are expected to form in northeast Ethiopia.
Western Region. The situation remained calm in September. Although good rains fell throughout the summer breeding areas in the northern Sahel of West Africa and conditions were favourable for breeding, only low numbers of adults and a few hoppers were detected in Mauritania and Chad while only adults were seen in Niger. There were reports of hoppers in northwest Mali and adults in the northeast but neither could be conﬁrmed by surveys due to insecurity. There is a potential risk that more locusts may be present than indicated by survey results, and this may become evident once vegetation dries out and adults form groups in areas that remain green in parts of Niger and Chad. In Mauritania, this could become evident as more adults appear in the northwest where breeding is expected to occur, causing locust numbers to increase further. Therefore, strict vigilance is required during the forecast period to detect those areas where gregarization could take place. In Northwest Africa, a few adult groups were breeding in irrigated areas of the Central Sahara in Algeria that were treated, and isolated adults were seen in northeast Morocco.
Central Region. During September, scattered adults were present and breeding in the interior of Sudan and western Eritrea. As breeding conditions were favourable over a widespread area, more adults may be present than indicated by survey results. This should become evident once vegetation dries out and adults form groups. The ﬁ rst signs of this appeared in eastern Sudan at the end of the month when an increasing number of adult groups and at least one swarm formed and were treated. More groups and small swarms are expected during October, mainly west of the Red Sea Hills, and some of these will move towards the winter breeding areas on the Red Sea coast of Sudan and southeast Egypt. No locusts were seen in Saudi Arabia and the situation remained unclear in Yemen with reports of breeding on the coast and a swarm in the highlands. As good rains fell on the Red Sea coast in both countries, small-scale breeding is expected to occur that will cause locust numbers to increase gradually. Local breeding continued in northeast Ethiopia where numerous small hopper bands formed and were treated. A few small swarms could form and move towards northern Somalia. No locusts were reported in Oman.
Eastern Region. The situation remained calm in September with only scattered adults present in a few places along both sides of the Indo-Pakistan border. Small-scale breeding may have occurred but locust numbers did not increase signiﬁcantly. The southwest monsoon withdrew from the area after mid-month. No signiﬁcant developments are likely.