Brian Rudman: Wētā sanctuary at zoo would be double win

Illustration / Peter Bromhead

COMMENT: In one of its dying gasps, the old Auckland City Council approved Auckland Zoo's $13 million plan to establish a 10-strong herd of Asian elephants roaming the forested hills above Western Springs Lake.

Luckily this madcap scheme somehow got lost in the excitement of setting up the new Super City - which was no doubt a relief to the neighbouring residents.

But it came back to me over the weekend as I read of a team of Auckland Zoo ectothermologists heading across the seas in the dead of night to liberate Tupperware container-loads of zoo-bred giant wētās on a remote island in the outer Hauraki Gulf.

These wētāpunga are the elephants of the insect world, the females weighing more than the average house sparrow.

They were once common in Auckland and Northland, but the kiore and later introduced predators reduced them to a last stand refuge on Little Barrier Island. Since 2012, Auckland Zoo has been breeding them up and has so far released more than 2200 on to pest free Gulf Islands like Tiritiri Matangi and Otata in The Noises.

I couldn't help thinking it's time they stopped running. If the zoo could build a fence to keep elephants in the wilderness alongside the zoo, then why not a predator-free fence around the same area to keep the vermin out, and our local endangered "elephant" insects, along with their indigenous lizard and bird bros, safe inside. A mini-version of Wellington's ground-breaking Zealandia Eco-Sanctuary.

The timing couldn't be better. Later this month, resource consent hearings begin over the Waitematā Local Board's plan to remove the remaining 200 or so unhealthy or dying pines from the 3.2ha block above the Western Springs Lake and replace them with native trees.

It so happens the zoo has an adjacent stand of mixed native and exotic trees which could be joined together and encircled with a predator-free fence to create an inner city sanctuary, complete with links to the sea via Meola Reef.

I know that these days the more radical of conservationists get rather sniffy about predator-free fences. They preach the big-bang theory of the whole country being predator free by 2050.

Well, I'm doing my little bit for that dream with a trap I keep baited in my backyard. But I also can't help thinking that a dry land "Tiritiri", such as Zealandia, and potentially Western Springs, where the lessons of conserving our wildlife are there for all to easily access, can only help.

The need is pressing. A recent report to the Waitematā board reveals that in the 10 years to 2015, "a total of 61.23ha of tree canopy was lost from the Waitematā Local Board" area. A comparison of aerial photographs over the decade revealed "a minimum of 12,879 trees were cleared".

There was no obvious reason for more than half of this urban forest clearance - no new structure or driveway had been added.

If this is representative of the isthmus as a whole, it suggests that the burgeoning Auckland isthmus urban forest seems to have peaked at the turn of the century and is now in serious decline. This is a blow for those who saw the new urban forest as a vital part of the native bird revival - providing the corridor for the rejuvenated flocks spreading out from their new predator-free Gulf Island nurseries, across the city to repopulate the Waitākere Ranges.

Given this privately owned suburban forest is in steady decline, public parks such as Western Springs and the adjacent zoo are last hope substitutes.

And with the zoo reinventing itself away from being a keeper of exotic foreign beasts to becoming more a conservator of the local endangered fauna, a mini-Zealandia along the shores of Lake Western Springs would tick several boxes.