Special report via Tony Orman
Invariably interference by Man into natural ecosystems is disastrous says the Sporting Hunters Outdoor Trust.
Trust spokesman Laurie Collins of the West Coast was commenting on a current controversy over wild cats. “Recent statements displaying a hatred of cats are wide the mark ecologically, whether the felines are domestic or wild. Cats are killers as any predator is. But they kill only for their needs, i.e. food. It’s no different to any predator -– Man included. They kill,” he said. Laurie Collins has had a wide experience in pest work. Initially as a young forestry trainee about 1958, when he worked on the first trials of 1080 poison in the Caples valley at Lake Wakatipu and then subsequent “pest” work with the Forest Service and regional councils. In addition he has had a life-long love of the wilderness recreationally. “Removing a predator from a food chain invariably has adverse effects. A classic case was Macquarie Island, south of Tasmania. a rainy, windswept place teeming with wildlife. But things changed due to Man’s interference,” he explained.
The changes began with the extermination of the feral cats between 1985 and 2000 in an attempt to restore the island and its bird population to its pristine state. Once cats were eliminated, there followed an explosion in the rabbit population. The feline predators had been removed from the food chain. Primarily the cats were keeping the rabbits in check.
Explosion
The explosion of rabbits devastated the island as copious tussock grasses which consolidated the steep slopes were almost entirely denuded. This result was a loss of habitat for nesting birds and an increased number of landslides. “You’d think people might learn from past mistakes because way back in 1867 the New Zealand weka was introduced as a source of food,” said Laurie Collins. Then weka put pressure on native Macquarie Island parakeet and rail, and the two species became extinct on the island. With less food weka numbers then declined plus killing of them towards the 1980s and the last weka was killed in 1988.
Feral cats had been recorded on the island way back in 1820. Everything was in equilibrium ecologically.
Same with 1080
Laurie Collins said 1080 poison in New Zealand used extensively by the Department of Conservation was a similar example of ill-advised interference. “It’s the same with 1080 poison in New Zealand. 1080 aerially spread for rats, knocks them back, to a low percentage with 10-15% off the rodents surviving. But rats are superbly prolific breeders. Eighteen months after 1080, the rats have bred back to pre-poison levels. Three years after poison the rat numbers are three to four times original numbers – a super plague of rats. Then the main predator of rats, stoats with abundant food, spiral upwards in a big population increase”. He said the rat explosions following 1080 aerial drops was in a Landcare Research study 2007.
The adverse effects of 1080 did not end there, as with greatly increased rat numbers, stoats whose main prey is rats and with more food, soared in numbers too. “All DoC and Ospri have achieved is population explosions of rats then stoats,” he said. “That’s why every four years or thereabouts, another poison drop has to be made. You’d think DoC would know better since it’s documented in Landcare Research work.”
Careless, thoughtless interference into Nature’s food chain equilibrium is invariably counter-productive and disastrous said Laurie Collins who added caution and thought are needed.
Mr Collins comments on 1080 and the subsequent rat population explosion which results afterwards should be known to DoC. They must realise that is why they have to come back in 4 years with another 1080 drop. It is there in landcare research work, Wendy Ruscoe scientist in 2007.
The overall theme here is the futility of man’s interfering with nature, I find.
Best expressed by the great late nature author Bill Benfield::
“Interfering with nature is like pushing against a spring,regardless of effort or money pushed at it, it will always return to its normal setting.”.
Wild cats are an interesting species.
Having been employed at the Fortex Seafield meat plant briefly in 1994 and charged with oversight of pest control, I was staggered at the numbers of feral cats that materialized around the condemned bins late at night despite an active control program.
Similarly when rabbit calcivirus, RCD, abruptly wiped out the rabbits on the Rakaia River bed numerous diseased and starving cats suddenley appeared during daylight hours.
Very much a population of predators that remains hidden out of sight if possible.
It seems hard to judge whether they cause net benefit or harm to healthy ecosystems.
It seems in all cases things find a balance whether or not mankind attempts to “manage” natural systems.
For that reason I do not condone the use of 1080. It has not achieved anything in the long term, it kills everything, and kills in an extremely inhumane manner.
A few years ago in North Sydney there was a campaign to eradicate foxes with 1080. A lot were wiped out and subsequently the food chain was disrupted. There was a massive increase in the number of rabbits and bandicoots in suburban gardens,
The overall theme here is the futility of man’s interfering with nature, I find.
Best expressed by the great late nature author Bill Benfield::
“Interfering with nature is like pushing against a spring,regardless of effort or money pushed at it, it will always return to its normal setting.”.
Talking to a chap who shot in the vine yards in Marlborough and who stated that he shot 4000 birds one year and there were 9 such shooters and there are many who don’t employ these chaps but do it themselves So if you drink wine you are responsible for having these birds shot not a few wild cats so again we stuff around with nature