Dispersal and Survival of Aedes albopictus (Diptera: Culicidae) Males in Italian Urban Areas and Significance for Sterile Insect Technique Application

Abstract

The dispersal and survival of laboratory-reared Aedes albopictus Skuse males were investigated during the summer of 2007 in three Northern Italy urban localities by mark-release-recapture techniques. Two marking methods were compared: one group of males was dusted with fluorescent pigments on the body (FP), and the other group was obtained from a strain whose natural infection of Wolbachia had been removed (WB0). FP- and WB0-marked males were released as adults and pupae, respectively, in one fixed station at each locality. Recaptures were performed by skilled technicians, within a radius of 350 m from the release site, on days 4, 5, and 7 after the release, and the males were collected while flying around the technician's body or in swarms. Recapture rates ranged from 0.63 to 4.72% for FP males and from 2.39 to 11.05% for WB0 males. The mean distance traveled for WB0 males was significantly higher than for FP males; no difference was observed between the dispersal distance measured for the males recaptured on human host versus males recaptured while swarming. No further increase of the dispersal occurred during the postrelease period investigated (from day 4 to day 7 after release). The mean survival rate at the release was 0.51 for FP-marked males and 0.81 for WB0 males. The data obtained are discussed for their significance in planning sterile insect technique programs against Ae. albopictus.

Pilot Field Trials With <I>Aedes albopictus</I> Irradiated Sterile Males in Italian Urban Areas

“…In consideration of the low male survival rate observed in harsh summer periods by Bellini et al (2010) in a markÐreleaseÐrecapture study, the optimization of sterile male release rates and intervals, as well as of the number of release stations per hectare require further investigations.…”

“…Wild male population density was estimated on the basis of the model developed by Carrieri et al (2011b) in similar environments to calculate the ratio between the number of females and the average number of eggs per ovitrap per hectare, which was 1.57 Ϯ 0.77, based on a female survival rate of 0.91. Male survival rate in northern Italy urban areas is lower with respect to female survival rate (from 0.52 to 0.97, Bellini et al 2010), and considering a mean male survival rate of 0.81 Ϯ 0.25, the ratio between the number of males and the average number eggs per ovitrap per hectare was 1.42 Ϯ 0.72 (Carrieri et al 2011b Other Mosquito Species. Apart from Ae.…”

Influence of Age and Nutritional Status on Flight Performance of the Asian Tiger Mosquito Aedes albopictus (Diptera: Culicidae)

“…albopictus has been investigated in the field. Mark-release-recapture experiments revealed the mean distance travelled by females (or males) was approximately 200 m, with maximal flight ranges between 50 to 325 m, as determined 4 to 23 days after release [31–33]. Another approach was to feed females with rubidium so that it would be incorporated into eggs and readily detected at oviposition sites during one gonotrophic cycle [34].…”

Novel Estimates ofAedes aegypti(Diptera: Culicidae) Population Size and Adult Survival Based onWolbachiaReleases

“…aegypti adult population. Bellini et al (2010) previously used Wolbachia in a MRR to estimate dispersal and survival in population of Aedes albopictus (Skuse) in Italy. In their case, Ae.…”