The Rodenticide Action Group Margaret River Region has recently sent an evidence-based submission to the APVMA (Australian Pesticides and Veterinary Medicines Authority) for their current review of anticoagulant rodenticide regulation. View here.

Our submission highlights the vulnerability of the Masked Owl in SW WA due to secondary poisoning by rodenticides, based on our evidence that  introduced rodents associated with human habitation are the primary prey, exacerbated the owl’s low reproductive rate.

We forwarded a detailed submission on 11 June 2020 to the APVMA for their 2020 review of anticoagulant rodenticide use. View here.  We understood that was to be the basis for decisions on regulation.  We have made a follow-up  submission in response to the APVMA’s decision to request more evidential support after a majority of the 3391 submissions advocated stricter regulation. View here.

Our main contribution is to highlight the susceptibility of the Masked Owl in SW WA to secondary poisoning by rodenticides, based on our extensive evidence that  introduced rodents associated with human habitation are the primary prey.

We also have evidence that the Masked Owl in SW WA  does not manage to breed every year and, when they do breed, only a couple of fledglings emerge from the nest. Of these, often only one survives to independence. Even if the low reproductive rate is natural and not a consequence of high rodenticide loads, this strategy certainly renders our Masked Owl population particularly vulnerable when faced with debilitation and death of adults and youngsters from likely constant rodenticide exposure.

In our submission we made five recommendations:

  1. An immediate overall ban on the sale and use of SGARs while this review of the science is conducted, with use only through specific approval.
  2. Learn from the Californian experience that half-way measures are insufficient and place a total ban on use of Second Generation Anticoagulant Rodenticides (SGARs) – unless  approved by the APVMA for specific exceptional circumstances such as eradication of rodents on conservation important islands.
  3. At the least,
  • SGARs should be removed from retail sale to the public by listing as Schedule 7 poisons, and
  • Strict requirements be placed on use by commercially trained and accredited operators.
  1. Allocation of funding for research to determine levels and impacts of exposure to SGARs in Australian wildlife  and the pathways by which this is occurring, with a commitment by the APVMA to take regulatory action where warranted by the findings.
  2. Encouragement for an industry funded stewardship scheme as established in Britain – including a monitoring program for a sentinel species, for which the Boobook is a leading candidate (Lohr 2018).

Other researchers and community groups  have submitted the growing body of evidence that  second generation anticoagulant rodenticides have an insidious capacity to permeate and accumulate throughout food webs.

How rodenticides permeate the food chain  is brilliantly illustrated in a poster by our Californian colleagues in RATS (Raptors Are The Solution)

This summer’s family of kombegaars (Tawny Frogmouths) living in a garden on the outskirts of Margaret River risk rodenticide intake not only from the mice but also invertebrates in their diet