Sprayed barriers of diflubenzuron for control of the migratory locust (Locusta migratoria capito (Sauss.)) [Orthoptera: Acrididae] in Madagascar: short-term impact on relative abundance of terrestrial non-target invertebrates

摘要: Abstract Relative abundance of terrestrial, non-target invertebrates in savannah grassland was monitored following large-scale field trials using the insect growth regulator (IGR) diflubenzuron applied as barrier treatments for control migratory locust Madagascar. Identical sampling techniques were employed to monitor at two different trial sites, separated by about 300 km; one treated with IGR barriers over an area 20 km 2 1993 and second, similarly 5 1994. Data collected more than species from 120 families 17 orders. Faunal composition sweep net catches similar order family level areas, but quite level. The majority sampled either occurred numbers too small be evaluated statistically or showed no evidence effects even within spray a 3 month period spraying. However, depending on timing spraying, relative both caterpillars [Lepidoptera] grasshoppers [Acrididae] declined treatment remained low several months. Adverse impacts spiders [Araneae] (particularly Salticidae), crickets [Orthoptera; Gryllidae] bugs [Heteroptera] could not discounted. Inter-barrier spaces, 500 m wide, acted true refugia, spraying fauna middle these areas. Diflubenzuron appear relatively safe short term, comparison other methods control. spaced 500–600 m, severe decline cannot dismissed ecologically insignificant whole further monitoring insects should accompany future use. technique seems likely environmentally acceptable, this can only confirmed after evaluation longer-term impacts.