<i>Cleopus japonicus</i> releases and distribution of the buddleia biological control agent in New Zealand

Abstract

The buddleia leaf weevil Cleopus japonicus was released in New Zealand by Scion in 2006 as a biological control agent for the weed Buddleja davidii One thousand C japonicus adults were released at each of five commercial forest sites in the North Island A further 33 releases of approximately 14910 C japonicus were made between 2006 and 2011 in the North and South Islands on both privately and publicallyowned land and sites of conservation importance The weevil is known to have established at all sites with the possible exception of one release made in 2007 Location data of C japonicus provided by local and regional councils DOC forest health officers and others have provided information on the spread of C japonicus These data show C japonicus has spread over 50 km from some release sites and is rapidly increasing in population density and distribution

Dispersal of the Scotch broom gall mite <i>Aceria genistae</i> implications for biocontrol

“…Further work is required to determine the reasons for the variation in A. genistae dispersal rates. As noted for Cleopus japonicus in New Zealand (Watson et al 2011a), dispersal rates may accelerate if A. genistae populations increase exponentially. Another possible factor is release size and the timing of release.…”