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[bobf <bobford79 AT yahoo.com>]

--- On Wed, 1/14/09, EarthNSky <erthnsky AT bellsouth.net> wrote:

...many people see the big picture of  things like losing the rainforest and 
climate change, but refuse to accept 'smaller' impacts...I put smaller in 
quotes because I do believe that there is something to the butterfly effect, 
and if so,something  small can become something big.
> 

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***** Like this story, Bev ?



Removing cats to protect birds backfires on island
      
Michael Casey, Ap Environmental Writer – Tue Jan 13, 9:18 am ETBANGKOK, 
Thailand – 

It seemed like a good idea at the time: Remove all the feral cats from a 
famous Australian island to save the native seabirds.

But the decision to eradicate the felines from Macquarie island allowed the 
rabbit population to explode and, in turn, destroy much of its fragile 
vegetation that birds depend on for cover, researchers said Tuesday.

Removing the cats from Macquarie "caused environmental devastation" that will 
cost authorities 24 million Australian dollars ($16.2 million) to remedy, 
Dana Bergstrom of the Australian Antarctic Division and her colleagues wrote 
in the British Ecological Society's Journal of Applied Ecology.

"Our study shows that between 2000 and 2007, there has been widespread 
ecosystem devastation and decades of conservation effort compromised," 
Bergstrom said in a statement.

The unintended consequences of the cat-removal project show the dangers of 
meddling with an ecosystem — even with the best of intentions — without 
thinking long and hard, the study said.

"The lessons for conservation agencies globally is that interventions should 
be comprehensive, and include risk assessments to explicitly consider and 
plan for indirect effects, or face substantial subsequent costs," Bergstrom 
said.

Located about halfway between Australia and the Antarctic continent, 
Macquarie was designated a World Heritage site in 1997 as the world's only 
island composed entirely of oceanic crust. It is known for its wind-swept 
landscape, and about 3.5 million seabirds and 80,000 elephant seals arrive 
there each year to breed.

The cats, rabbits, rats and mice are all nonnative species to Macquarie, 
probably introduced in the past 100 years by passing ships. Authorities have 
struggled for decades to remove them.

The invader predators menaced the native seabirds, some of them threatened 
species. So in 1995, the Parks and Wildlife Service of Tasmania that manages 
Macquarie tried to undo the damage by removing most of the cats.

Several conservation groups including the International Union for 
Conservation of Nature and Birds Australia said the problem was not the 
original eradication effort itself — but that it didn't go far enough. They 
said the project should have taken aim at all the invasive mammals on the 
island at once.

"What was wrong was that the rabbits were not eradicated at the same time as 
the cats," University of Auckland Prof. Mick Clout, who also is a member of 
the Union's invasive species specialist group. "It would have been ideal if 
the cats and rabbits were eradicated at the same time, or the rabbits first 
and the cats subsequently."

Liz Wren, a spokeswoman for the Parks and Wildlife Service of Tasmania, said 
authorities were aware from the beginning that removing the feral cats would 
increase the rabbit population. But at the time, researchers argued it was 
worth the risk considering the damage the cats were doing to the seabird 
populations.

"The alternative was to accept the known and extensive impacts of cats and 
not do anything for fear of other unknown impacts," Wren said. "Since cats 
were eradicated, the grey petrel successfully bred on the island for the 
first time in a century and the recovery of Antarctic prions has continued 
since the eradication of feral cats."

Now, the parks service has a new plan to finish the job, using technology and 
poisons that weren't available a decade ago.

Wren said plans to eradicate both rabbits as well as rats and mice from the 
island will begin in 2010. Helicopters using global positioning systems will 
drop poisonous bait that targets all three pests. Later, teams will shoot, 
fumigate and trap the remaining rabbits, she said.

Some of the earlier critics are now behind this latest eradication effort, 
saying it should help the island's ecosystem fully recover because it would 
remove the last remaining invasive species.

"Without this action, there will be serious long-term consequences for the 
majestic seabirds which nest on the island including the four threatened 
albatross species, and for the health of the island ecosystem as a whole," 
said Dean Ingwersen, Bird Australia's threatened bird network coordinator.

"We believe that the process they are going to follow uses best practice for 
this type of work," Ingwersen said. "And that all possible ramifications have 
now been considered."

http://news.yahoo.com/s/ap/20090113/ap_on_re_au_an/as_australia_rabbit_infestation