Endangered native snail & introduced Himalayan tahrs thrived together until the New Zealand government got involved
WELLINGTON, New Zealand––Plans for a cull of 17,500 Himalayan mountain tahr across the Southern Alps of New Zealand are on hold, likely to be scaled down but not abandoned, after the New Zealand Tahr Foundation and allied organizations representing trophy hunters threw their political weight behind opposition previously voiced mostly by a handful of self-described “compassionate conservationists.”
Himalayan mountain tahr are rare members of the mountain goat family.
The cull, as planned, would kill about half of by far the largest population of Himalayan mountain tahr population left in the world, grown from just five tahr, including a single male, introduced in 1904.
New Zealand conservation minister Eugenie Sage envisioned in recent parliamentary discussion that the doomed tahrs would be cornered by helicopter, then shotgunned.
“The department will be using aerial control, it needs to do the control operation now, and yes it will be using shotguns in the same way that hunters use guns to kill tahr themselves,” Sage told National Party member of parliament Todd McClay, apparently unaware that hunters normally stalk and pick off just one tahr at a time, from the ground, using high-powered rifles.
Tahr red-listed globally
Red-listed as “Near Threatened” by the International Union for the Conservation of Nature since 2008, a few hundred Himalayan mountain tahrs persist––but are seldom seen––in native habitat at high elevations in China, India, Nepal, and perhaps Bhutan.
Some Himalayan mountain tahrs survive on U.S. hunting ranches, with small feral populations in Argentina and––maybe––on Table Mountain, overlooking Cape Town, South Africa.
The Table Mountain tahr, if any remain, are descended from a pair who escaped in 1935 on their first day at the long defunct Groot Schnur Zoo.
Table Mountain National Park management declared the South African population extinct, after killing 138 tahr in a six-month purge, but hiker and videographer Kyle Mijlof in 2017 distributed photos of a trio of tahr on the mountainside.
“No decision has been made”
“The Department of Conservation says no decision has been made on details” of the New Zealand cull, reported Simon Hartley for the Otago Daily Times on October 5, 2018.
“The recent Tahr Liaison Group made good progress, but the Department of Conservation has not finalized any plan,” said New Zealand tahr control director Andy Roberts.
“The Tahr Liaison Group,” explained Hartley, “consists of 13 organizations, including the New Zealand Deerstalkers Association, New Zealand Tahr Foundation, New Zealand Game Animal Council, Federated Farmers, and Forest & Bird,” formally the Royal Forest & Bird Protection Society of New Zealand.
“Adamant the tahr cull will go ahead”
“Adamant the tahr cull will go ahead,” Hartley continued, Sage on September 29, 2018 stumped for support at the nation’s largest hunting event, the Sika Show and Competition in Taupo.
The New Zealand Tahr Foundation meanwhile announced that it had raised $146,000 in New Zealand dollars, worth about $100,000 in U.S. funds, toward litigation against the tahr cull, and had won pledges “from at least 11 of the major ammunition importers and manufacturers around the country,” Hartley wrote, “that they will not sell the Department of Conservation the estimated 100,000 rounds of ammunition it would need for Ms. Sage’s contentious tahr cull.
Kill-happy minister was flack for birders
“Ms Sage [was already] under fire on several fronts,” Hartley noted, “with her widespread use of Compound 1080 poison across the country to eradicate brush possums.”
Sage, before entering politics as a member of the New Zealand Green Party in 2007, was a publicist for Forest & Bird, a vehement foe of introduced species since 1924.
Named conservation minister and associate environment minister in 2017, as part of a coalition government, Sage almost immediately announced an $81.2 million, four-year scheme to try to poison every mammalian predator in New Zealand with air drops of the pesticide Compound 1080 on an unprecedented scale.
School killing contests
Though still used by USDA Wildlife Services to a limited extent to kill coyotes, Compound 1080 was banned from general use in the U.S. in 1972. New Zealand is now believed to use as much as 90% of all the Compound 1080 deployed worldwide.
Sage has also encouraged school-sponsored contests that encourage children to kill brush possums, feral cats, rats, and even rabbits, not actually a predatory species.
Many tahr eradication attempts
The putsch against Himalayan mountain tahrs coincides with the Sage scheme, but follows previous attempts to eradicate the hardy species beginning before Sage was born.
Air drops of Compound 1080, opposed by hunters, failed to extirpate tahrs in 1960, despite killing tahrs in large numbers.
A 1993 Himalayan Tahr Control Plan emphasized “aerial game recovery operations, recreational and safari hunting as primary means of control,” aiming to keep the tahr population below 10,000.
More than 24,000 tahr have been killed by New Zealand government hunters since 1993, and many more have been killed by trophy hunters. Nonetheless, the New Zealand tahr population has more than tripled, since the habitat is favorable for them, with no native rival species and no native predators.
“The cull is opposed by the [opposition] National Party as well as by hunters,” noted Radio New Zealand report Eric Frykberg on September 28, 2018.
Mountain goats persecuted in U.S., too
Sage’s zeal to rid New Zealand of Himalayan mountain tahr echoes the zeal of the U.S. National Park Service and the Washington Department of Fish & Wildlife to extirpate mountain goats from Olympic National Park, where they have thrived since a small population was introduced from Alaska in 1924––14 years before the park itself was designated.
Mountain goats are considered native in the Cascades mountains, barely 100 miles east, but not to the Olympics. A capture team translocated 114 mountain goats from Olympic National Park to the Cascades in mid-September 2018. Another 260 mountain goats are to be translocated, according to the current National Park Service plan. The plan anticipates that 275 to 325 mountain goats will elude capture and eventually be shot.
Both the New Zealand population of Himalayan mountain tahr and the Olympic National Park mountain goats are blamed for allegedly damaging alpine habitat for other rare and endangered species.
But scapegoating tahr has not come along with equal New Zealand government concern for Powelliphanta augusta, a highly endangered giant carnivorous snail which for about 100 years shared habitat with Himalayan mountain tahr.
“When you think of New Zealand’s native species, you may imagine comical looking birds wandering native bush on foot, or giant weta clinging to mossy branches,” began Charlie Mitchell, national correspondent for the online periodical Muck Rack, on October 6, 2018.
Ice cream boxes
Instead, Mitchell explained, “One of our rarest native species has a much stranger habitat. It lives in hundreds of plastic boxes, many of which are used ice-cream containers,” in a cold storage facility behind a Department of Conservation office.
There, Mitchell wrote, three Department of Conservation rangers “carefully note what the captives eat, how much they weigh each month, and how they breed. Their handwritten observations are stored in thick binders.
“Despite a famously slow gait,” Mitchell noted, “New Zealand’s native snails strike their prey like snakes, snapping onto a worm and sucking it up like spaghetti. A video of a captive P. augusta eating a worm has nearly two million views on YouTube, about as viral as any obscure snail could hope to go.”
Native habitat no longer exists
But except for the YouTube gawkers, few of whom are likely to remember the name of the species, and the caretakers, hardly anyone knows Powelliphanta augusta snails exist.
“The species is named for its original habitat, a cloudy mountaintop above the sea,” Mitchell recounted. “By the time the species was formally described,” in 2008, “its habitat had already been replaced,” years earlier.
That habitat, Mitchell detailed, was Mount Augustus, a “mountain ridge where rain fell in sheets, as if tipped from a bucket; where the ground froze over in the winter and titanic gales hissed over the Tasman, rattling the tiny trees and shrubs that to us would have looked like a bonsai forest It took the [snail] species millions of years to adjust to that brutal environment, which it had slowly conquered while the mountain emerged from the clash of tectonic plates.”
Tahr were no problem, but coal mining was
Browsing by Himalyan mountain tahr on Mount Augustus appears not to have affected Powelliphanta augusta, though the species had yet to be identified, let alone inventoried. But Mount Augustus was destroyed by Solid Energy, a state-owned coal mining company, when it expanded the Stockton Mine, one of New Zealand’s largest and oldest, in 2005.
Forest & Bird fought in court to save the last Powelliphanta augusta habitat, but lost. Volunteers searching on their hands and knees recovered 6,000 snails and 8,000 eggs from the site before it was destroyed, but the eight refrigerators bought to house them were not big enough to hold them all––and Powelliphanta augusta turned out to be actually three subspecies, dwelling in different parts of the mine site. Only 24 snails of the “northern” variety were found, of whom just five remain today.
Currently, Mitchell wrote, “There are 1400 snails in the fridges, which is nearing capacity. Around 300 of them once lived on the mountain. Some of the snails are nearing 30 years old and have grown so large they would fill the palm of a child’s hand. They’ve had babies and their babies have had babies.”
The New Zealand Department of Conservation still has not identified anywhere to put them. Solid Energy, which spent $10 million New Zealand dollars to move them, and $7 million to look after them in their refrigerators, went broke and was liquidated in March 2018, owing more than $400 million.
“The taxpayer continues to subsidize Solid Energy by paying for the snails it was willing to sacrifice,” Mitchell concluded. “The term for the things an industry abandons before they’re used up is a ‘stranded asset’. Usually it’s a power plant, or a mine. In this case, it’s a native species.”
Does Compound 1080 kill snails?
Eventually, Mitchell anticipates, the New Zealand government may abandon Powelliphanta augusta too. Restoring suitable habitat in the pit where Mount Augustus once was would be prohibitively costly, if it could even be done.
Because brush possums eat snails, among other things, the Compound 1080 campaign is touted as potentially beneficial to Powelliphanta augusta and other rare New Zealand snail species––but Compound 1080 may also kill snails, according to the small amount of research ever done on the matter.
Meanwhile, worms edible by Powelliphanta augusta proliferate in the excrement of herbivorous mammals. Himalayan mountain tahr poop serves nicely as a worm growth medium at the elevations Powelliphanta augusta favors.