Pollinators are important natural agents for fruit and seed formation in most tree crops and the use of appropriate sampling methods is fundamental in studying their population. A study to develop surveying and monitoring protocols for cocoa pollinators was undertaken in Ghana. Yellow, white and blue UV-bright painted pan traps (UVPPT), McPhail traps and motorized aspirators were used to sample pollinators of cocoa for 13 successive months, after 6 days assessment of the effectiveness of the traps and diurnal active period of the pollinators. The peak pollinating period of cocoa by ceratopogonid midges was between 07.00 and 12.00 h, as previously reported. All three methods were effective in sampling ceratopogonid midges with the UVPPT being the most efficient in terms of sampling effort. The number of ceratopogonid midges caught by the yellow-UVPPT was significantly higher than that by blue- and white-UVPPT. The diversity of midges caught could not be determined due to taxonomic difficulties, and thus all the three colours of UVPPT should be used until efficiency in terms of diversity is determined. It is reported here that the meliponine bee Liotrigona parvula Darchen visits cocoa flowers and thus their effectiveness in cocoa pollination should be investigated.

We studied the behaviour of three Anastrepha spp. (Diptera: Tephritidae) that were attracted to protein hydrolysate in glass McPhail traps, hung on an 8 m tall wild mango tree, Mangifera indica at three different heights. Out of 665 flies that landed on the exterior of the trap only 31 % were caught. Females represented 60.2 % of all flies trapped. The intermediate trap hung at 5m caught the most flies (57.5%). We observed a great deal of feeding activity (on trap, leaves, branches and fruit) including régurgitation and reingestion of liquid food droplets. When not on the trap surface, flies were more commonly seen on leaves than on branches and fruits. Inter- and intraspecific encounters between all Anastrepha spp. and both sexes were commonly recorded. Males were observed calling alone or in leks. All leks were formed on leaves and on two occasions included individuals of two species. Our observations suggested that the McPhail traps attracted different Anastrepha spp. with varying degrees of intensity.