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Feral cats (Felis catus) pose a significant threat to wildlife, agriculture, and human health through predation, disease transmission, and competition with native animals. Controlling feral cats and their impacts, however, is challenging. New and emerging 1080‐based feral cat baits have shown promising results in western and central Australia; however, the safety of these new baits for nontarget species in eastern Australia, where many native animals are more sensitive to compound 1080 (sodium fluoroacetate) than their western conspecifics, has not been assessed. We investigated the uptake of 499 toxic Eradicat® baits by nontarget animals across five different eastern Australian environs and the uptake of nontoxic Eradicat and Hisstory® baits at an additional two sites. Using field‐based observations of species eating or removing baits, we determined that 13 nontarget species (eight mammals, four birds, and one reptile) were at high risk of individual mortality, with individuals of 11 of those 13 species (seven mammals, four birds) observed consuming enough toxic Eradicat in a single visit to ingest a lethal dose of 1080. Feral cats (the target species) consumed only 3.1% of monitored baits, which was only 52% of the 31 baits they encountered. We recommend undertaking targeted population monitoring of species identified at high risk of individual mortality, to determine whether Eradicat baits present a population‐level risk to these species. Our findings suggest that the small‐sized Eradicat baits present a greater risk to nontarget species in eastern Australia than the larger traditional 1080‐based meat baits used for the control of wild dogs and foxes. Our study highlights the importance of performing risk assessments for different bait types, even when the same toxin is used, and of performing site‐specific nontarget risk assessments of new baits such as Eradicat to assist developing guidelines for their safe and effective use in different environs. Integr Environ Assess Manag 2022;18:224–244. © 2021 State of Queensland. Integrated Environmental Assessment and Management © 2021 SETAC. KEY POINTS: New feral cat baits have shown promising results in western and central Australia and are considered safe for many non‐target native species in those regions due to a long‐term evolutionary exposure to fluoroacetate‐bearing plants, giving them an increased tolerance to the toxin used in baits. We present a comprehensive field assessment of the risk of Eradicat® feral cat baits to non‐target species in eastern Australian environs, where native animals do not share the same evolutionary exposure and tolerance to the toxin as their western conspecifics. Most baits were swiftly removed by non‐target native mammals, birds and reptiles, 13 of which were at high risk of individual mortality, with most species consuming more than enough toxic bait in a single visit to ingest a lethal dose. Our findings will help inform operational risk assessments, thereby enabling land managers to adapt control programs to manage non‐target risks to local faunal communities on a site‐by‐site basis in accordance with local management requirements and objectives. [ABSTRACT FROM AUTHOR]

Fresh meat baits containing sodium fluoroacetate (1080) are widely used for controlling feral pigs in Queensland, but there is a potential poisoning risk to non-target species. This study investigated the non-target species interactions with meat bait by comparing the time until first approach, investigation, sample and consumption, and whether dying bait green would reduce interactions. A trial assessing species interactions with undyed bait was completed at Culgoa Floodplain National Park, Queensland. Meat baits were monitored for 79 consecutive days with camera traps. Of 40 baits, 100% were approached, 35% investigated (moved) and 25% sampled, and 25% consumed. Monitors approached (P < 0.05) and investigated (P < 0.05) the bait more rapidly than pigs or birds, but the median time until first sampling was not significantly different (P > 0.05), and did not consume any entire bait. A trial was conducted at Whetstone State Forest, southern Queensland, with green-dyed and undyed baits monitored for eight consecutive days with cameras. Of 60 baits, 92% were approached and also investigated by one or more non-target species. Most (85%) were sampled and 57% were consumed, with monitors having slightly more interaction with undyed baits than with green-dyed baits. Mean time until first approach and sample differed significantly between species groups (P = 0.038 and 0.007 respectively) with birds approaching sooner (P < 0.05) and monitors sampling later (P < 0.05) than other (unknown) species (P > 0.05). Undyed bait was sampled earlier (mean 2.19 days) than green-dyed bait (2.7 days) (P = 0.003). Data from the two trials demonstrate that many non-target species regularly visit and sample baits. The use of green-dyed baits may help reduce non-target uptake, but testing is required to determine the effect on attractiveness to feral pigs. Further research is recommended to quantify the benefits of potential strategies to reduce the non-target uptake of meat baits to help improve the availability of bait to feral pigs. [ABSTRACT FROM AUTHOR]

(I) Bounty payments were used as an index of the distribution and population fluctuations of dingoes and feral pigs in Queensland. (2) Both are widespread in Queensland but there is evidence of increased numbers and a wider distribution of feral pigs in the latter part of the survey period, associated with reduced numbers of dingòs following a sodium monofluroacetate (" 1080") poisoning campaign. (3) Dingoes and, more particularly, feral pigs showed indications of delayed density-dependent mortality. (4) The causes of mortality in dingo populations are unknown but may include social restrictions on breeding. (5) Mortality of feral pigs was, significantly related to dingo numbers (predation) and to rainfall (food supply). Variation, in annual rainfall had a more pronounced effect on feral pig mortality in areas of low rainfall than in areas of higher rainfall. [ABSTRACT FROM AUTHOR]