ARS | Publication request: THE MOVEMENT OF STERILE MALE BACTROCERA CUCURBITAE (DIPTERA: TEPHRITIDAE) IN A HAWAIIAN AGROECOSYSTEM.

Submitted to: Journal of Economic Entomology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: June 16, 2005
Publication Date: October 1, 2005
Citation: Peck, S.L., Mcquate, G.T., Vargas, R.I., Seager, D.C., Revis, H.C., Jang, E.B., Mcinnis, D.O. 2005. The Movement of Sterile Male Bactrocera cucurbitae (Diptera: Tephritidae) in a Hawaiian Agroecosystem. J. Econ Entomol. 98:1539-1550.

Interpretive Summary: The melon fly, Bactrocera cucurbitae Coquillett, was discovered to have invaded the Hawaiian Island chain in 1895. In 1999 a program sponsored by the USDA-Agricultural Research Service (ARS) to control melon fly and other tephritid pests in Hawaii over a wide area was initiated on the islands of Hawaii, Maui, and Oahu. To control these flies in an area-wide setting, understanding how flies move within the landscape is important. To explore the movement of this fly, we examined the movement of marked, male, sterile, lab-reared B. cucurbitae on the island of Hawaii in an agricultural setting. Two releases of dyed, sterile flies consisting of ca 15,000 flies, were released 6 weeks apart. Released flies were trapped back using traps baited with a male attractant. The recapture data from these two releases suggest that, in the Hawaiian agricultural areas where the area-wide control is being sought, melon flies do not move extensively when there are abundant larval host and adult roosting sites. The flies appeared to disperse throughout the study area but then move very little thereafter. Over the course of the study, only one fly made it the maximum distance that we could detect fly movement (approximately 2000 m in two weeks). The estimated low-movement rate in the present study has positive implications for area-wide programs designed to control melon fly populations. This study suggests that, if agricultural areas are sufficiently isolated, area-wide programs are likely to be successful. However, because of the possibility of rare recolonization events, monitoring will have to be maintained because the flies do seem able to move significant distances if areas are without needed resources such as food, mates, or host plants for oviposition.

Technical Abstract: The melon fly, Bactrocera cucurbitae Coquillett, was discovered to have invaded the Hawaiian Island chain in 1895. In 1999 a program sponsored by the USDA-Agricultural Research Service (ARS) to control melon fly and other tephritid pests in Hawaii over a wide area was initiated on the islands of Hawaii, Maui, and Oahu. To control these flies in an area-wide setting, understanding how flies move within the landscape is important. To explore the movement of this fly, we examined the movement of marked, male, sterile, lab-reared B. cucurbitae on the island of Hawaii in an agricultural setting. Two releases of dyed, sterile flies consisting of ca 15,000 flies, were released 6 weeks apart. Released flies were trapped back using Moroccan traps baited with a male attractant. These two releases suggest that in the Hawaiian agricultural areas where the area-wide control is being sought, melon flies do not move extensively when there are abundant larval host and adult roosting sites. Over the course of this study, only one fly made it the maximum distance that we could detect fly movement (approximately 2000 m in two weeks). From these data, it appears that the flies dispersed throughout the study area but then moved very little thereafter. This is very apparent in the second release where the recovery rate after the second week was still fairly high, suggesting that if there are plenty of host fields and roosting sites the flies are unlikely to move.