Long-term sampling of gamma sterilised male Glossina austeni (Diptera : Glossinidae) with sticky panels on Unguja Island (Zanzibar)

Daily catches of gamma sterilised male Glossina austeni Newstead with exper imental sticky panels were analysed from March 1996 to July 1997. The flies were released weekly by light aircraft over primary and secondary forest e cosystems of Unguja Island, Zanzibar. In the primary forest, the cross-shap ed royal blue XT panel (two interlocking panels of each 70 x 60 cm) trapped significantly more flies than the royal blue-white leg panel (panel with a body of 65 x 30 cm and two legs of each 15 x 15 cm) in all months, except in July 1996 and July 1997, In the same habitat, the cross-shaped royal blu e-white leg panel (two interlocking leg panels) trapped from 1.7 (not signi ficant) to 3.0 times (highly significant) as many flies as the standard leg panel depending on the season. Significantly more flies were trapped with the cross-shaped XT panel than with the leg panel in the secondary forest c ompared to the primary forest. Catches of the cross-shaped XT panel on each of a series of days, correlated well with those of the leg panel on the sa me day, except for panels deployed in the primary forest during the hot-dry and the beginning of the cold-dry season. Catches of the cross-shaped leg panel correlated less well with the catches of the standard leg panel in th e primary forest. The data presented indicate that the behavioural response s in time and space of sterile male G. austeni are influenced by the type o f trapping device used. (C) 2001 Elsevier Science B.V. All rights reserved.