Distribution and Movement of Adult Diaprepes abbreviatus (Coleoptera: Curculionidae) in a Florida Citrus Grove

Abstract

JSTOR is a not-for-profit service that helps scholars, researchers, and students discover, use, and build upon a wide range of content in a trusted digital archive. We use information technology and tools to increase productivity and facilitate new forms of scholarship. For more information about JSTOR, please contact support@jstor.org.. Florida Entomological Society is collaborating with JSTOR to digitize, preserve and extend access to The Florida Entomologist. ABSTRACTOver 10 weeks, 765 adult, feral Diaprepes abbreviatus were captured from 750 young citrus trees by dislodging them into inverted umbrellas. Newly captured weevils were distributed evenly among plots throughout the experimental site. Five hundred eighty of these weevils were marked and released; 146 were recovered. Recaptured (marked) weevils tended to stay close to the release point. Because recaptured weevils were not homogenously distributed, a mark-release method for a population estimation was untenable. Weevils were recaptured at distances up to 120 m from the release point, the farthest distance checked. There were no differences between males and females in the numbers and distances moved. Marked females were recovered at the experimental site over a longer time period than marked males. Weevils were recaptured within 6 weeks of marking, but none after 6 weeks from first capture. Over the 10 week experimental period, Malaise and Tedders traps captured 0 and 2 weevils, respectively, compared to the 765 weevils captured with the beat method. Average adults per tree ranged from 0.016 to 0.376 per week with an overall average of 0.172 ? 0.140, enough adult weevils to thoroughly infest all trees with larvae.

Contributions of demography and dispersal parameters to the spatial spread of a stage‐structured insect invasion

“…We fit a LaPlace dispersal kernel (K ¼ e Àjxj/a /2a) to the DRW dispersal data using maximum likelihood methods (Burnham and Anderson 2002) and used the likelihood profile method (Hilborn and Mangel 1997) to generate a 95% CI for the LaPlace parameter a, which is the mean dispersal distance. The LaPlace distribution provided a good fit to the dispersal data of Nigg et al (2001), much better than a normal distribution (DAIC ¼ 15.4). The reproductive status of the weevils used in the dispersal experiment was not determined; thus separate dispersal estimates for pre-reproductive and mature adults were not available.…”

“…Adults can live for more than five months and females can lay .6000 eggs over their lifetimes. Adult weevils are capable fliers but move relatively short distances (Nigg et al 2001). In southern Florida and in its native Puerto Rico, the weevil has overlapping generations and shows persistent stage structure, with adults occurring year-round (Beavers and Selhime 1976).…”

“…Our model considers only females; there is no evidence for sex bias in dispersal behavior (Nigg et al 2001). We separated larvae and adults each into two stages because the empirical literature suggested that these distinctions were biologically meaningful (Table 1).…”

“…DRW dispersal data came from a field experiment conducted by Nigg et al (2001). These investigators marked, released, and resighted adult weevils in a citrus grove in Lake County, Florida at weekly intervals over a 10-week period.…”

“…Data are from Nigg et al (2001). perturbation analysis and calculated partial rank correlation coefficients (PRCC) to describe the statistical effect of each input parameter on model output (Tenhumberg et al 2008).…”