Use of liquid deltamethrin in modified, host-targeted bait tubes for control of fleas on sciurid rodents in northern California.

The efficacy of liquid deltamethrin was evaluated for controlling fleas on golden-mantled ground squirrels, Spermophilus lateralis, and chipmunks, Tamias amoenus and T. senex. A host-targeted bait tube was modified to deliver insecticide to visiting rodents during a seven-week trial conducted in the Southern Cascade Mountains of northern California. A single deltamethrin treatment with one replenishment of bait provided effective flea control on rodents within one week of deployment of bait tubes. A second treatment accompanied by two bait replenishments during the following two-week period maintained effective control throughout the seven-week period, even though all bait tubes were removed from the site after three weeks. Our results suggest that the use of modified bait tubes treated with liquid deltamethrin can provide an effective, economical, and efficient means of controlling vector fleas on the primary disease amplifying rodent hosts in this plague endemic region of California.