Swarms moving in the Horn of Africa and Arabia
During the past week, strong northerly winds have carried small mature (yellow) swarmlets south from southern Somalia to northeast and eastern Kenya (Mandera, Wajir, Garissa, Isiolo, Tana River, and Kitui counties). In the past few days, a few swarmlets continued further south to Taita Taveta county and nearly reached northeast Tanzania where they could appear in Kilimanjaro, Manyara, and Tanga regions until Sunday 22 November; thereafter, the winds will shift and no longer come from the north.
Although some of the swarmlets that arrived in Kenya may have already laid eggs in southern Somalia before their arrival, there remains a risk of further egg-laying in sandy areas of northeast Kenya where recent rains have fallen. In this case, hatching and hopper band formation can be expected in early December. In the northwest, control operations are underway against small hopper bands that are forming from local breeding in Samburu county.
Breeding continues in central Somalia and eastern Ethiopia where hopper bands are present, and a new generation of immature swarms will start forming by the end of this month. Swarm formation will continue throughout December because of widespread hatching and band formation that occurred this past week. From the second week of December onwards, several waves of numerous swarms can be expected to move south in Somalia and Ethiopia, reaching northern Kenya. Intensive aerial and ground control operations continue in both countries.
Strong southerly winds over the Arabian Peninsula during the past week caused immature swarms to move from the interior of Yemen to the Asir Mountains in southwest Saudi Arabia as well as in the interior north of Riyadh. Some of these swarms may continue further north towards Iraq in the next few days until the southerly winds subside.
In Eritrea, ground control operations continue against groups of hoppers and adults in winter breeding areas on the northern coast of the Red Sea. In Sudan, aerial and ground control operations continue against hopper bands and swarms in the summer breeding areas east of the Nile Valley. Control is also underway against maturing swarms in the winter breeding areas on the Red Sea coast in Tokar Delta. In southeast Egypt, control teams are treating a few hopper groups and bands that have formed in one area.
In Yemen, several swarms were seen recently in the central highlands moving from the summer breeding areas of the interior to the Red Sea coast for winter breeding.