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Permanent Interstate Committee for Drought Control in the Sahel AGRHYMET Régional Centre CILSS’Special Information Bulletin N°02/08 LOCUST SITUATION IN MAURITANIA Although the Situation is under Control in the Accessible Areas of North-western Mauritania However, one should Remain Vigilant Background to the Current Situation : During the rainy season of 2008, from June to October, Mauritania locust situation was regularly monitored by the National Anti-Locust Centre (CNLA). Scattered adults were observed in July, in the summer breeding area in south-eastern Mauritania, particularly in Hodh El Chargui located at 16°43N and 07°47W. The situation evolved into an increase in locust populations and the presence of solitary adults in the two Hodhs, Assaba, Tagant and Brakna, during the month of August (see ﬁgure 1). In September, hoppers were present in the Trarza and Brakna Wilayas. In the other sites surveyed, adults, including some mature locusts in the process of copulating and laying eggs, were observed; as a result, the situation required increased vigilance. In October, ecological conditions deteriorated in the summer breeding area in the South-East, whilst they became favorable in the areas of Aoukar, Boutilimit and Agane and in south-eastern Inchiri as well as Trarza Wilayas (autumn/fall breeding area). Thus, the locust populations moved to these areas where solitary adults started to breed and hopper densities became increasingly signiﬁcant. Dris Zemour Nouadhibou Adrar Inchiri Tagant Hodh Chargui Trarza Brakna Hodh Charbi Assaba Figure1: Mauritania’s desert locust breeding areas (Source: http://www.claa.mr/fr/centre.htm#cpem) Centre Régional AGRHYMET BP:11011 Niamey (Niger) TEL:(227)20 31 53 16 / 20 31 56 36. Site Web: www.agrhymet.ne Locust Situation in November and Early December 2008 The locust populations kept on increasing and the ﬁrst treatments were carried out on 150 ha of land located at 18°53N/13°45W. They continued in the same area and covered 925 ha. As the vegetation continued to dry out in the South-East, the locust populations kept on increasing in the Inchiri area. Late instar hoppers and young adults were observed in an area characterized by small basins and interdunal hollows measuring 2 to 10 ha and 100 m2 to 1 ha, respectively. Hopper density was in the range of 2 to 3/sq. meter depending on the topography and vegetation conditions, whilst adult numbers increased in the very green Schouvia purpurea stands Thus, at the end of the assessment carried out by the CNLA teams, during the ﬁrst dekad of December 2008, the surface area infested by hoppers and adults was estimated at 40.000 ha, in the Inchiri, Adrar and Trarza areas. This infested zone, which is difﬁcult to access, is frequently swept by rising sand during that period of the year. These are two major constraints which could limit the actions envisaged by ground control teams. However, CNLA took measures to strengthen the survey and control system and to revitalize the CNLA central command post. Progress of the Locust Situation in December 2008 The progress of the locust situation was regularly disseminated by CNLA, through news updates on the following dates 15/12, 17/12, 22/12 and 27/12/2008. It emanates from these news updates that the locust situation was gradually brought under control and even under full control, as a result of the actions taken by CNLA and the ground teams. Thus, out of the 40,000 ha considered infested during the ﬁrst dekad of December, 14,027 were treated on 27 December 2008. Locust density in the remaining surface areas was low and will require treatments only in the event of grouping. These infestations by solitary transient locusts, which consisted of 98% of immature adults, were conﬁned to the Zgueimir, south-eastern Inchiri and Akles areas, which were difﬁcult to access and characterized by vegetation made up of still green Schouvia, Fagonia sp. in the process of drying out and dried out Tribulus sp, temperature and soil moisture conditions remained favorable in some places. Conclusion and Way Forward In the accessible zones of the infested region located in the autumn (fall) breeding area of North-Western Mauritania, the locust situation was brought under control thanks to the control methodologist implemented by the National Anti-Locust Centre of this country. However, there were persistent uncertainties in the zones, which were difﬁcult to access at the level of interdunal hollows. Considering the observed locust development stages and ecological conditions, there are fears that solitary transient locusts could not only move northward, but also mature and breed in less and less vast pockets where transformation into the gregarious phase could be favored. The same situation could occur in areas, which are difﬁcult to access, where the control of locust populations is impossible and the situation in terms of infestations remains unknown. It should be however noted that the low temperatures recorded in these areas during the period under review, were expected to favor survey and control operations because locust activities were slowed down. It was highly probable that a situation similar to that observed in Mauritania prevailed in northern Mali and Niger, where no survey was possible due to insecurity. Thus, although the situation was under control in the accessible areas of Mauritania, one should remain vigilant because there is still a risk. One should bear in mind that there will always be escape locusts, which will move to northern Mauritania and southern Maghreb. In addition, as the Maghreb countries keep a close watch on locusts, there are great hopes that the situation could be brought under control in this area even though there are uncertainties as far as Mali and Niger are concerned.
"LOCUST SITUATION IN MAURITANIA A"