How to poison a rat – DOC’s Te Maruia 1080 Operation.
8 July 2019 DOC Application form for permission to allow the Te Mauia 1080 application submitted.
12 July 2019 the application was given initial approval. However due inaccuracies – a change in the application rate, and permissions “pending”, caused the initial application to be amended in a subsequent application dated August 2019.
6th September 2019 Permission ID: 6040500 Te Maruia – Rat Control Operation was granted with immediate effect from on for after 1 September 2019 until 13 December 2019.
A higher application rate of up to 2kg/ha of 15g/kg 6g aerial baits (Pestex) was approved
The Permission identified 20 separate areas administered by DOC, LINZ and the Buller Council – Stewardship areas and Scenic Reserves centred around Springs Junction, parts of Lake Sumner Forest Park, Otira –Kopara Forest Conservation area, Victoria Forest Park, Inangahua Forest Conservation area, Palmer Road Conservation Area, Nelson Lakes National Park, A Fixed Marginal Strip of the Rahu River, A gravel reserve –Red Stream.
In all 69,910 ha was targeted taking in the both sides of the Maruia River from Lewis Pass to end several km downstream of Maruia settlement. With the aerial application centred on Springs Junction, large areas of the Upper Grey catchment were included in the drop zone. (1)
18 and 19 September 2019 pre-feeding was completed. Clear fine weather on 19 November allowed the flight paths of helicopters operation both sides of Maruia to be observed. (2)
2 & 3 November the poison operation was completed (1)
7 November 2019, a heavy rain event occurred in the catchments of the Te Maruia aerial poison operation. There was a “localized” spike in river flows &/or rain records 7-8 November recorded by Council monitoring sites.
8 November the first sighting of dead rats on Westport beaches was reported (3)
9 November more rats and Sooty Shearwaters were found at Waimangaroa Beach, 8 km north, and further rats found north of here. Locals picked up a trailer load of dead rats together with fish, birds and a crayfish. DOC took the crayfish but did not test it. (3)
Doc Western South Island operations manager Mark Davis acknowledges the Te Maruia drop a week ago “however while it is conceivable the rats had come from the 1080 drops reports of dead fish and birds along with the rats were not consistent with the way 1080 is supposed to work”. (4)
DOC and the local council erect warning signs and bury carcases. A calf, goat, weka, octopus, Black Petrels are mentioned in other reports. (5)
A Murchison local investigated the Buller River tracing dead rats lodged high up in drift wood upstream in the Buller River to its Junction with the Maruia and further up along the banks of the Maruia River. He met a DOC worker who claimed he was unable to find dead rats? The Murchison local had a report of dead rats at the mouth of the Grey River from a friend at Greymouth. (6)
22 November 1. News: What killed the Westport rats?:
· Flora and Fauna of Aotearoa and Clean Green New Zealand report samples collected by volunteers confirmed substances present were “almost certainly” the result of 1080
[A Facebook image shows a graph confirming the presence of a green dye present in the gut of a rat taken off a HPLC spectrophotometer screen. Apparently this lab is fearful of being identified by authorities (7)]
· University of Canterbury toxicologist professor Ian Shaw said he is curious about the case – the 1080 poison – fluoroacetate causes a reaction that creates fluorocitrate. This is well known and what DOC should have looked for. Sitting on the beach in the warmth it is quite likely the 1080 would have been broken down. While cautioning that he is a toxicologist, Shaw doubted the theories of mass deaths based on drowning &/or hunger.
DOC said the question ( fluorocitrate) should be directed to Landcare Research.
· University of Auckland’s Dr James Russell with a PhD in biology and statistics said rats did not normally move in a Pied Piper mass event to account for mass drownings. He proposed a burst dam together with a big weather event combined with the high rat population as an explanation.
· Director of NZ’s Biological Heritage and Natural Science Challenge, Dr Andrea Byrom blamed high rat density and weather as the most likely culprits
· DOC did not test for any other toxins. Nor did they test any fish or marine life. “….secondary poisoning was considered unlikely …… crayfish are not known to scavenge rats….. all carcasses had been disposed of and could not be tested further”.
3 December 2019 OIA request from NZFFA to DOC received:
· None of the animals tested contained 1080 refer to link on our website
· No dead trout were found by the Department or reported by the public
· 2-3 November was confirmed as date of poison application
· No investigation was undertaken along the Buller River between the drop zone and affected beaches
· Application rate up to 2 kg/ha, 0.15% bait aerially sown and some hand sown bait.
· Landcare Research, Lincoln, Toxicology report: received 12 November - 8 rats and 1 weka all samples < MDL for 1080.
[The website link gave DOC’s press statement – “Testing shows no 1080 in rats” November 20, 2019
The School of Veterinary Science Pathology Reports:
On 12 November a weka missing its head and an adult male and a female rate sent.
Provisional diagnosis: Unknown cause of death. Organs moderately autolysed. Report dated 12/11/19
On 13 November a sub adult male, a sub adult female and a rat of unknown sex was sent.
Provisional diagnosis: Unknown cause of death. Report dated 14/11/19
Samples to be sent for 1080 testing from all but the rat of unknown sex (too decomposed to be useful)
Comment – no histopathology was attempted. Result of toxicology not available. Gross examination of these (autolysed) carcasses would not allow diagnosis of an acute death from 1080 – “going through the motions”?)]
DOC’s response to this event was woeful.
No effort was made to warn the public of the potential risk to themselves or their pets – Doc simply helped bury the evidence.
Was there an investigation of the lower Buller River by DOC as reported by an eye witness?
Why were dead marine animals, fish, and birds not tested?
Why were inappropriate tests used to determine of 1080 was involved
Why were insufficient samples sent?
Why has DOC not stepped up and taken ownership of polluting two West Coast River catchments and several beaches 100s of kms from their Te Maruia 1080 operation?