A comparison of four rodent control methods in Philippine experimental rice fields

Four rodent control techniques-sustained baiting (SB) with cournachlor. pulsed baiting (PB) with brodifacoum. a lethal electrified barrier (LEB), and a nonlethal electrified barrier (NLEB)-were evaluated on the experimental fann of the International Rice Research Institute (IRRI) in the Philippines. A fifth treatment (no experimental rodent control) was established for reference. Mean tiller damage and rodent activity, respectively. near harvest were 1.00/;1 and 1.5% in the LEB plots, 1.6% and 18.0% in the SB plots, 2.1% and 16.O'X in the PB plots, and 4.1% and 32.5% in the NLEB plots. Highest mean tiller damage (9.3%) and rodcnt activity (56.0%) occurred in plots with no experimental rodent control. Both baiting methods (SB and PB) were less expensive than barrier method5 (LEB and NLEB). During an 80-day crop protection period prevalent on the IRRl experimental farm, the total cost per hectare (US$) for protecting experimental plots from rodent damage was $26 for SB. $27 for PB, $268 for NLEB, and S1285 for LEB. Baiting methods were morc cost-effective and arc recommended for general rodent control on research farnls that can tolerate < 2% rodent damage without losing experimental data. For srnall research plots demanding a greater degree of protection, an effective barrier system such as the LEB or a combination of the NLEB and LEB should be used. Published by Elsevier Science Ltd. tiol~~roi.~l.v: Rodent control: Rodcnticide baiting; Susta~ned baiting; Pulscd baiting; Barriers; Electric fencca; Coumachlor; Brodifacoum: Rlcefield rats