The use of poison baits to control feral cats and red foxes in arid South Australia II. Bait type, placement, lures and non-target uptake

Abstract

Context Poison baits are often used to control both foxes and feral cats but success varies considerably. Aims This study investigated the influence of bait type, placement and lures on bait uptake by the feral cat, red fox and non-target species to improve baiting success and reduce non-target uptake. Methods Six short field trials were implemented during autumn and winter over a five-year period in northern South Australia. Key results Results suggest that poison baiting with Eradicat or dried kangaroo meat baits was inefficient for feral cats due to both low rates of bait detection and poor ingestion rates for baits that were encountered. Cats consumed more baits on dunes than swales and uptake was higher under bushes than in open areas. The use of auditory or olfactory lures adjacent to baits did not increase ingestion rates. Foxes consumed more baits encountered than cats and exhibited no preference between Eradicat and kangaroo meat baits. Bait uptake by native non-target species averaged between 14 and 57% of baits during the six trials, accounting for up to 90% of total bait uptake. Corvid species were primarily responsible for non-target uptake. Threatened mammal species investigated and nibbled baits but rarely consumed them; however, corvids and some common rodent species ingested enough poison to potentially receive a lethal dose. Conclusions It is likely that several factors contributed to poor bait uptake by cats including the presence of alternative prey, a preference for live prey, an aversion to scavenging or eating unfamiliar foods and a stronger reliance on visual rather than olfactory cues for locating food. Implications Further trials for control of feral cats should concentrate on increasing ingestion rates without the requirement for hunger through either involuntary ingestion via grooming or development of a highly palatable bait.

Dying to be clean: pen trials of novel cat and fox control devices

“…Read (2010) also demonstrated the potential to deliver poison to feral cats through compulsive grooming, which circum vents their frequent aversion to consuming baits and other challenges of bait delivery of toxins including palatability and bait degradation issues. Avoiding a food-based deliv ery also improves target specificity by reducing significant non-target uptake (Algar et al 2007;Moseby et al 2011), a key requirement of acceptable pest animal control tech niques (Sanders and Maloney 2002;King et al 2007). A novel automated device that sprays poison onto the coat of an animal of a specific size or shape, hereby coined "grooming trap," will restrict exposure of most non-target species to toxins.…”

“…Effective control of introduced feral cats (Felis catus) and red foxes (Vulpes vulpes) is a priority for the conservation of many small to medium sized mammals and ground nesting birds (Smith and Quin 1996;Risbey et al 2000), and is integral to the successful reintroductions of a range of threatened species both in Australasia and other regions (Short et al 1992;Gibson et al 1994;Priddel and Wheeler 2004;Moseby et al 2011).…”

First in, first served: uptake of 1080 poison fox baits in south-west Western Australia

“…Only one fox took the bait on the six occasions when the bait was still present. The rate of bait uptake by target species can be influenced also by other factors, including habitat type (Trewhella et al 1991;Carter and Luck 2013), season (Woodford et al 2012), bait type (van Polanen Petel et al 2001) and the availability of alternative food sources (Roberts et al 2006;Moseby et al 2011). Therefore, if foxes are likely to take only a small proportion of presented baits under most circumstances, the reduction in the number of baits available owing to non-target bait take becomes a significant problem.…”

“…Thomson and Kok 2002), the higher incidence of non-target species taking baits in mixed and open forests (e.g. Allen et al 1989;Moseby et al 2011) may simply reflect a greater diversity and abundance of wildlife in native vegetation sites than in agricultural lands.…”

“…The results of eight Australian studies that identified species bait take have been summarised (Table 1). Birds appear to be the primary non-target group responsible for taking baits laid on the surface (Thomson and Kok 2002;Marlow et al 2008;Moseby et al 2011).…”