Flight Phenology of Male Cactoblastis Cactorum (Lepidoptera: Pyralidae) at Different Latitudes in the Southeastern United States (Report‪)‬

The cactus feeding pyralid Cactoblastis cactorum (Berg) has the notoriety as both a beneficial introduced insect and a harmful alien insect pest. In the 1920s the moth was first used as a classical biological control agent against non-native prickly pear cactus (Opuntia spp.) in Australia (Dodd 1940; Mann 1970). Because of the success of this insect to help reclaim some 24 million ha of prickly pear infested lands in Australia (Raghu & Walton 2007), the insect was used as a biological control agent in other parts of the world (Pettey 1948; Fullaway 1954; Zimmermann et al. 2004). Initially, C. cactorum was used to manage non-native species of prickly pear. However, with the introduction of C. cactorum into the Caribbean Island of Nevis in 1957 (Simmonds & Bennett 1966), the moth was used to attack native Opuntia species. At the time, concern for native species and biodiversity was superseded by the need to help subsistence farmers reclaim pastures overrun with prickly pears (Zimmermann et al. 2000). Through natural and/or human-aided dispersal, the moth made its way throughout most of the Caribbean and, unfortunately, was found in the Florida Keys in 1989 (Dickle 1991). Introduction and establishment of C. cactorum into Florida from the Caribbean occurred at least twice (Simonsen et al. 2008) with human intervention (Pemberton 1995; Simonsen et al. 2008). The moth's spread and attack of native Opuntia spp. in the United States threatens rare and endangered species (Stiling et al. 2000), ornamental interests (Mahr 2001), and agricultural systems in the United States and Mexico (Soberon et al. 2001; Vigueras & Portillo 2001; Garrett 2004). Studies have been conducted to identify the distribution (Stiling 2002) and dispersal (Hight et al. 2002; Solis et al. 2004) of C. cactorum on North American prickly pear species. Since the initial find of C. cactorum in 1989, the moth has spread rapidly along the Gulf and Atlantic Coasts and now occurs as far west as Petit Bois and Horn Islands off the coast of Mississippi (unpublished data), and as far north as Bull Island, South Carolina (R. Westbrooks, USGS, personnel observation, 2004). The rate of spread away from coastal areas into the Florida Peninsula has been slower, but the occurrence of the insect in the interior is relatively common as far north as central Florida (Orlando) (unpublished data).