A vertical bait station for black rats (Rattus rattus) that reduces bait take by a sympatric native rodent

Abstract

Abstract. Novel bait stations can be used as a targeted method of delivering bait by exploiting behavioural traits of the target species. On Muttonbird Island, New South Wales, the black rat (Rattus rattus) has been baited to aid the conservation of the island's wedge-tailed shearwater (Ardenna pacifica) colony, which may result in poisoning of the sympatric swamp rat (Rattus lutreolus). We aimed to design a bait station that R. rattus could reach, but that R. lutreolus could not. We found that 11 (92%) of 12 captive R. rattus reached the bait chambers by climbing a 50-cm vertical pipe, whereas only four (18%) of 22 R. lutreolus reached these bait stations. In a field trial on Muttonbird Island R. rattus entered the bait chamber on an average of 5.3 events per night of vertical bait station deployment, but R. lutreolus did not enter the stations. In a field trial on the mainland at a site with a high density of R. lutreolus, this species was detected in one vertical bait station five times, equating to an average of 0.017 events per night of vertical bait station deployment. We conclude that R. rattus readily climbs a 50-cm pipe to enter the bait station, whereas R. lutreolus rarely or never does on Muttonbird Island or at the mainland site.

Use of rodenticide bait stations by commensal rodents at the urban–wildland interface: Insights for management to reduce nontarget exposure

“…45 This underscores the need to monitor and remove rat carcasses regularly after applying rodenticides, 39,46 particularly in yards that are close to natural areas and relatively accessible. As has been shown in other studies, [28][29][30][31] the risk of primary exposure to native rodents could also be reduced significantly by simply elevating bait stations off the ground, with no apparent loss of rodenticide availability to target pest species such as black rats. Rats actually entered elevated stations at a higher rate (64-70%) than ground stations (59-63%).…”

“…Because black rats are excellent climbers, 27 elevating bait stations may reduce exposure of wildlife species to rodenticides, as has been examined for R. rattus elsewhere. [28][29][30][31] Lastly, we examined characteristics of yards that were visited by rats and wild rodents to determine if the use of anticoagulant rodenticides should be avoided in certain types of yards to reduce opportunities for nontarget exposure.…”

Baiting location affects anticoagulant rodenticide exposure of non‐target small mammals on farms

“…Only in regions where genetic resistance of rodents to ARs occurs, 55 highly potent SGARs such as brodifacoum should be used 13,56 . In addition, bait station design could be modified to limit the access of non‐target species 86,87 but little is known about their effect on the exposure of non‐target species. In any case, care has to be taken that bait station design is suitable for quick uptake of an effective dose 88 to ensure that losses in stored produce or the risk of human infection with rodent‐borne disease are minimized 44 …”

How dangerous conservation ideas can develop through citation errors

“…This is another miscitation and another "Whisper" with rats being now linked to suppressing populations of native mammals. Zewe et al (2013) also mis-cite Burbidge and Manly (2002) in a very similar way "Invasive rodents have been implicated in the decline and extinction of insular seabirds (Atkinson 1985;Towns et al 2006;Jones et al 2008;Banks and Hughes 2012) and mammals (Burbidge et al 1997;Burbidge 1999;Burbidge and Manly 2002;Harris 2009;Banks and Hughes 2012). "…”