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Aerial 1080 poisoning in New Zealand: Reasons for concern

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Abstract

Reasons to be concerned about the widespread use of aerially distributed food baits containing 1080 poison (sodium monofluoroacetate) for pest control in New Zealand are evident in scientific publications and government reviews and reports. Many hazardous properties and a lack of scientific knowledge of the effects of 1080 were described in a comprehensive report by the Environmental Risk Management Authority in 2007. These findings are presented followed by examination of evidence of problems with aerial 1080 use: 1) Increased pest impacts following poisoning due to competitive release of rats and mice, and prey-switching by predators; 2) Reduced efficacy with repeated poisoning of rats; 3) Deaths of native birds; and 4) Lack of scientific justification and monitoring of aerial 1080 use. It is concluded that there is an urgent need to bring scientific methodology into pest management.
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... A recently published review paper (Pollard, 2016) demonstrating reasons for concern regarding the Government's policy of widespread aerial poisoning with 1080 was sent to several government ministers and staff in August 2016. A three-page letter in reply, supporting the use of 1080, was received from the Department of Conservation's Susan Timmins (Acting Director, Threats) (DoC letter, see Appendix 1). ...
... 1080 is not only toxic to birds, but also bacteria, fungi, plants, nematodes and insects (ERMA Review, 2007). When broadcast in cereal-based food pellets, the poison is also available on fragments, in baitdust and spread by animals (see Pollard, 2016), as well as in water (Srinivasan et al., 2012). An experimental study found a severe negative impact of aerial 1080 on a wide range of terrestrial invertebrates, persisting for at least a year in some species (Meads, 1994, unpublished, cited in Whiting-O'Keefe & Whiting-O'Keefe, 2007). ...
... " Net benefit " as used by DoC is the recorded mortality of marked birds due to poisoning, and the recorded increase in nesting success following the poisoning. But nesting success of survivors increases when a bird population is culled (see Pollard, 2016). Mortality from predators is likely to be artificially created by DoC's intensive monitoring of nests, which increases the risks to birds as noted by Ellenberg et al. (2015), pp. ...
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A recent review highlighting several reasons for concern regarding the New Zealand Government’s policy of widespread aerial poisoning with sodium monofluoroacetate (1080), was sent to several Government ministers and staff (in August 2016). A letter in reply, in support of the ongoing use of 1080, was received from the Department of Conservation (DoC). The letter claims that there is foundational evidence aerial 1080 poisoning is ‘safe’, will retain its efficacy against rats throughout repeated applications, has desirable biodiversity outcomes, and that there are no current alternatives to its continued use. These claims are refuted based on documented evidence. Further, examination of documents concerning the management of two species, kea (Nestor notabilis) and mohua (Mohoua ochrocephala), reveals no scientific, ecological basis supporting pest control by DoC. There is an urgent need to review conservation management in New Zealand.
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