Amitus hesperidum- a natural enemy of citrus blackfly (CBF) was imported into Trinidad in April 2000 and releases began in June 2000 in commercial citrus fields. An island wide survey was conducted in February 2001 to determine the distribution of Amitus, 8 months after initial releases. Leaf samples were collected from 100 farms across six counties. Counts of pupae with parasite exit holes, pupae with CBF exit holes and unhatched pupae were recorded. Leaves were also incubated in an insectary for emergence of adult Amitus. On a county basis average parasitism of 34%, 31%, 27%, 25%, 16% and 9% occurred in counties St. Patrick, Caroni, St. George, Victoria, St. Andrew/St.David and Nariva/Mayaro respectively. On a farm basis parasitism levels of 87 %(Penal) and 100% (Flanagin Town, Tableland) were observed at release and non-release sites respectively. Amitus adults were recovered at 32 farms of which, 14 were Amitus release sites, while 18 farms were non-release sites. Ratios of unhatched pupae to emerged Amitus adults as high as 1:3 were observed at both release and non-release sites in counties St. George and St. Patrick respectively. The average distance between nonrelease sites and the closest release site was 4.41cm.


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