1080

A presentation to the Tree Crops Association on 27th April by Sandra Jack, Community Relations Officer, Department of Conservation, Auckland Area Office

1080 is a complex and emotive issue for both “sides”. The last time 1080 was used in the Auckland area was on Motuihe in 2002. The island is now home to kiwi, kokako, saddleback, shore skink etc

Context

• • DOC looks at the “big picture” of biodiversity recovery. The Animal Health Board’s focus is on killing possums to control bovine Tb for the farming and dairy industry.
  • 1080 works and is one of a small range of options to control animals that damage our native flora and fauna.
  • DOC wouldn’t use 1080 unless there was a net conservation benefit and doing nothing is not an option.
  • It comes down to choosing between rats, mice, stoats and possums OR kiwi, kokako, kereru, skinks, weta, frogs etc
  • The methods DOC use have been cleared by the government and DOC funds research into better alternatives

So what is 1080?

• • A toxin - sodium monofluoroacetate which was first produced in a lab in Belgium in 1896.
  • It’s the man made version of the chemical fluoroacetate which is produced by plants to stop them from being eaten by mammals and insects ie. it is naturally occurring
  • “1080” is simply the number given by the American lab when it was tested as a rat poison in 1944.
  • It is formed into a pellet which contains 0.15% 1080 toxin and the other 99.85% being made up of cereal colouring and flavouring etc.
  • 1080 works by interfering with the energy pathway within cells known as the “Krebs cycle”.
  • It has a lag time of 30 minutes to 3 hours until the animal is noticeably ill. There is no effective antidote. Some treatments are available but they need to be administered early.

Effect on animals

• • The toxicity if 1080 poses no significant risk to the environment if applied properly.
  • Mammals are most susceptible.
  • Herbivores die of cardiac failure. In carnivores it affects the central nervous system causing respiratory failure. Sometimes both occur.
  • Reptiles and frogs are less susceptible and fish even less, with practically no toxicity to freshwater invertebrates.
  • Unfortunately dogs are 13 times more susceptible than possums. The main risk to dogs is when they are able to eat the carcasses of animals that have died of 1080 (scavenging etc). A dog poisoned by 1080 is very distressing to observe and difficult to treat.
  • All 1080 operations are required to publicly consult with the effected community and install warning signs.
  • Deer damage forest eco systems by foraging selectively and pigs damage the forest undergrowth and are known to eat native frogs, snails etc. Effective deer repellent of cereal and carrot bait has been developed. This increases the cost of baiting but works to minimise deer kill.

1080 and native birds

• • Basically any risk to birds is outweighed by the bumper breeding that happens after pest species (predatory species like rats, possums and stoats) are removed. Bykill of more susceptible smaller birds is usually low.
  • Some bird species are more susceptible than others because of their feeding behaviour eg. ground feeding birds like ducks and pukeko are more vulnerable than bush birds.
  • No kiwi have died from 1080 operations.
  • There have been a number of successes with bird recovery including kiwi and whio (native blue duck) in Tongariro.
  • A recent outcome of the aerial drop at Kahurangi national park has shown all kea survived.

Effects on human health?

• • 1080 is a deadly poison but most NZers will never come into contact with it.
  • The highest exposure is if you are involved with the actual pest control (where precautions are taken and monitoring is done) or if you are the manufacturing chemist.
  • The bait has a low concentration hence is less of a risk than the pure toxin.
  • 1080 is broken down and /or eliminated from the body quickly (within a few days) so accumulation is unlikely.
  • There is ongoing research being conducted regarding human health and 1080 to ensure our practises are safe.

Why do we use 1080 in NZ?

• • It is relatively safe and effective toxin which has been available since the 1950s when possum control started on a large scale.
  • It does not persist in living organisms or the environment.
  • Nowadays a lot more is known about this toxin and the bait it is delivered in.
  • New Zealand is one of the biggest users of 1080 and there is a good reason for that as most other countries have native carnivores/mammals which are susceptible to 1080. A major exception being Australia whose carnivores have evolved in the presence of naturally produced 1080 and are tolerant of it.

Why does DOC use 1080?

• • DOC is a govt department tasked with protecting NZ’s natural and historic heritage.
  • DOC manages about one third of New Zealand on behalf of the public plus marine reserves.
  • A total of 8.5 million ha and 3.5 million hectares of marine reserves and sanctuaries.
  • Animal pests that need to be controlled: rodents, mustelids, possums, deer, pigs, rabbits, feral cats, hedgehogs etc.
  • NZ has 31% of its original forests and 5% of wetlands remaining.
  • 60% of NZ is now in agriculture leaving some native remnants.
  • 33 native species have become extinct and there are 2800 threatened species.

Concerns

• • 1080 is poisonous to a wide range of animals including birds, dogs, pigs and deer.
  • There is no antidote.
  • It is applied by aerial and ground application.
  • Suspected accumulation in the environment.
  • Suspected poisoning of animals and people through waterways.

Who is opposing 1080?

• • The Graf brothers and their film Poisoning Paradise - they don’t need to be accountable and give references (DOC does).
  • Hunters – 1080 reduces densities of deer and pigs, make hunting more difficult.
  • People generally opposed to the use of toxins/poisons.
  • People generally sceptical of anything the government does.
  • People concerned about animal ethics.

Things to note

• • All methods of pest animal control have welfare issues (including trapping and hunting).
  • What about the welfare of our native species if no control is carried out? Some are faced with extinction unless something is done.
  • DOC is working to improve humaneness of its methods e.g. the DOC 200 trap.
  • Aerial drops have proved to more cost effective than ground-based methods.

How persistent is 1080

• • 1080 is not persistent in the environment. It is dispersed and broken down quickly by micro organisms in the soil (fungi and bacteria).
  • Temperature and moisture (rainfall) determine how quickly it is broken down.
  • It is broken down quickly by the plants that absorb it and the animals that eat it (if they don’t die). Often a “caution period” is placed on taking animals to eat from an area where 1080 (and any other toxin) has been used.

1080 in water

• • Risks are negligible - there have been 18 years of monitoring (2098 water samples taken).
  • The amounts are lower than naturally occur in tea ie. low levels (non hazardous and short lived). No 1080 has ever been detected in public water sources.
  • No significant or prolonged contamination of surface waters, therefore no significant risk to human health.

1080 and plant uptake

• • Puha -1080 appears to occur naturally at concentration similar to tea.
  • Watercress -1080 uptake from bait in close proximity at very low levels and rapidly eliminated by the plant.
  • These results were found during Lincoln University/Landcare Research/Tuhoe and Ngai Tahu field studies on 1080 uptake in puha and watercress, published in Jan 2009.

Aerial Control Refinements

• • Aerial application has been improved by the use of GPS technology and “sowing rates” have been greatly reduced.
  • The quality of the bait has improved along with better public consultation.
  • This has all led to greater efficiency, better kill rates and lower risk.
  • Ground based pest control is generally used for maintenance operations in small areas or in contentious areas such as water catchments.
  • The majority of DOC pest control is ground based however at places such as Mt Egmont national park ground control isn’t an option due to the terrain. Also opossums have small home ranges so traps and bait stations would need to be a minimum of 100 100m apart. This would involve cutting thousands of kilometres of lines through native forest and hundreds of stream crossing for contractors to negotiate.

What are the alternatives to aerial 1080?

• • Other toxins eg. brodifacoum.
  • Ground control – remember most DOC possum work is ground control.
  • Trapping - $ and research is continuing to produce better trap options e.g. DOC200 and “The Henry” trap (automatically resets itself and is fired using a gas canister – up to 12 kills).

The future

• • 1080 is not applied annually (usually every 3-5 years).
  • Need to further align operations by DOC and AHB.
  • Further research is being carried out – takes time and costs money.

Toxins available in since 1990s

• • Cholecalciferol for possums (1995) and rats (2008)
  • Brodifacoum restricted by DOC (residue concerns)
  • More 1st generation anticoagulant baits for rodent control (pidone, dipacinone, coumatetraly)
  • However 1080 remains the most suitable and only registered toxin for aerial application
  • PAPP for stoats (in progress)
  • Widespread acceptance of bait-bags for ground control of possums (cyanide cholecalciferol, 1080)
  • Long life baits (1080 and cholecalciferol)

Fur trade and possums

• • The bounty system does not work
  • Fewer animals means it’s not worth it
  • Can get a vested interest in “farming” the animals e.g. possums introduced in Northland
  • Economics die out before conservation kicks in
  • In the meantime DOC needs to control pests and make decisions

Reassessment process

• • Asked for by DOC and AHB
  • Erma produced an evaluation and review (E&R) report with recommendations
  • 1406 public submissions – submitters invited to respond at publics hearings
  • Committee considered the application, written submissions, hearing presentations, the E&R Report and a report from the Maori Advisory Committee
  • ERMA decision (Aug 2007): Allow continued use of 1080 (the benefits outweigh the risks). Additional controls and recommendations for tighter management/monitoring of aerial operations.
  • 2008 report can be found at www.epa.govt.nz

Summary - doing nothing is not an option

• • WE ARE DAMNED IF WE DO AND DAMMED IF WE DON'T.................
  • Pests are not going to go away anytime soon
  • 1080 works
  • Working on better options
  • In the meantime DOC has to carry out our responsibility using the techniques we have available

Contact

• • Sandra Jack, Ranger, Community Relations, Auckland Area Office, Dept of Conservation
  • Phone 09 445 9142 Fax 09 445 9637
  • DDI 09 445 9751
  • New Zealand Government, Department of Conservation - www.doc.govt.nz

Additional info about bats (following question during session):

From DOC’s “Bat (Peka Peka) Recovery Plan”:

“Cyanide, 1080, phosphorus, and anti-coagulant toxins are used in a variety of forms to control or eliminate browsers and rodents in localities where bats are also present. One case of a short-tailed bat dying as a result of eating cyanide possum bait is documented (Daniel and Williams 1984). Short-tailed bats spend a proportion of their time foraging on the forest floor, and are therefore likely to encounter ground laid poisons baits… Long-tailed bats are aerial feeders and are therefore not likely to encounter poison baits.”

Evidence given in the Environment Court by John Lyall (DOC Technical Support Officer, Terrestrial Fauna in Hokitika) regarding  application of 1080 poison in the Taipo and Franz Josef/Waiho areas details why any risk to bats from the proposed 1080 poisoning programme is remote, and that there are some possible benefits to bats should they use the 1080 “Application Areas” at times. More specifically:

“Short-tailed bats have a diverse diet. They are primarily insectivorous, but also eat nectar, pollen and fruit (Daniel, 1976; Arkins et al., 1999).  However, it is extremely unlikely short-tailed bats will consume carrot or grained based baits. Feeding trials with captive short-tailed bats, and a trial in which fluorescent dyed non-toxic baits were broadcast in an area inhabited by short-tailed bats, showed that short-tailed bats did not consume carrot or grained based baits that are commonly used with 1080 and second-generation anticoagulants (Lloyd, 1994; Lloyd, 2001).

A potential risk to short-tailed bats is secondary poisoning by bats consuming arthropods that feed on toxic baits (Lloyd and McQueen 2000; Sherley et al., 2000).  However, no  harmful impacts were detected in short-tailed bat populations that were monitored through two aerially broadcast poisoning operations using pollard baits, one on Codfish Island using brodifacoum (Sedgeley & Anderson, 2000) , and one in Rangataua Forest in the central North Island using 1080 (Lloyd & McQueen, 2002).”

In addition, Colin O’Donnell (DOC Scientific Officer with our Research and Development Unit) has some unpublished data from the Eglinton Valley. In the Eglinton the short-tailed bat numbers have been increasing since the use of 1080 started in 2000 (used in 2000, 2002, 2003, 2006, 2010 - mixture of bait stations and local aerial).

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