Friday, December 16, 2011

NZ Lizards face grim fate if not helped (Via Herp Digest)

Lizards face grim fate if not helped, New Zeland's Commonn, McCanns skink,common gecko and the green or jeweled gecko.
by Tracy Miles 12/1/11,Timaru Herald, New Zealand

Attempts are being made to save South Canterbury's remaining lizard populations but fears are that loss of habitat will increase in coming years.

Piles of stones that have lain in South Canterbury paddocks, sometimes cleared from land by farmers more than a century ago, have become home to the common skink.
However, the Rangitata South Irrigation Project is expected to see changes to farming in the area, including moves to dairy farming.

The stone rows, described by Timaru teacher and lizard researcher Hermann Frank as "unique habitats" could well become a thing of the past, as fencelines are removed to allow for large irrigators.
The irrigation project is aimed at providing more reliable irrigation and will service 16,000 hectares of farmland between the Rangitata and Orari rivers, from Arundel to the coast.

The water is expected to be available in 2013.

In South Canterbury excluding the Mackenzie, the once widespread so-called common skink is now isolated to farmland, such as in the stone rows or piles, to gardens and along some beaches.

Mr Frank instigated the first systematic survey of lizards in South Canterbury, excluding the Mackenzie, in 2008, working for a year to identify where the district's lizards are.

He found four species, with what was the common skink being made up of two distinct species, the common (breeding in the stone piles) and the McCanns skink; and two species of gecko, the common gecko and the "very, very rare" green or jewelled gecko.

In a joint project between the Timaru District Council, Forest & Bird and Mr Frank, a disused TDC roading shingle quarry near the Orari Bridge by Geraldine is being prepared as a potential new lizard habitat for endangered colonies.

Mr Frank has also been working to establish connections with farmers to help avert the destruction of the district's common skink population.

He said he needs farmers to let him know well in advance if stones had to be removed so the skinks could be caught and relocated.

He said despite his efforts, stone piles had gone without him being alerted, or he learned about it "right at the time".

There were ways of catching the skinks but it took about two months, and could not be done during winter when they were inactive.

Older people had memories of lizards, from when they were more common, and from trips to the Mackenzie country, but for younger generations many had not seen a lizard and that could explain a lack of awareness, indifference, or them being made low priority.

Mr Frank said a management plan was being created for the quarry which would be made ready with dryland plants such as tussock, coprosma and matagouri, and by creating hiding places for the lizards. However, it was not intended to relocate them there except as an emergency measure.

If we don't try to preserve the remaining lizard populations of New Zealand, "most certainly we will lose them forever," said Timaru lizard researcher Hermann Frank.

The green jewelled gecko, which lives in native vegetation rather than on the ground, is a threatened species and has been targeted by wildlife smugglers.

In South Canterbury this gecko is very rare, Mr Frank said.

"There are virtually only three populations in South Canterbury," making their situation precarious.
It would take a 10-year period of study to get a clearer idea what their numbers are doing, said Mr Frank, who now spends most of his lizard study time hunting for jewelled geckos at weekends, observing the three known populations and hoping to find more.

He cannot reveal where the jewelled lizard populations are locally because of the trade in endangered species.

However, he said after development, pests are the second-biggest threat and appropriate ways of pest control were still being explored.

Weeds were also a threat, with broom and gorse encroaching on native bush being sprayed by farmers, killing the native bush as well.

"The main thing for all the lizards is to protect the habitat so there is no destruction or development."
For New Zealand's lizards as a whole, some species now only survive on predator-free islands and wildlife reserves.

New Zealand's lizard populations were unusual in that there were so many species, 90, for the country's small size - about half skink and half gecko.

Also, New Zealand lizards (all but one species) were the only ones to give birth to live babies, rather than laying eggs, the usual reptilian means of reproduction.
Geckos usually only have twins, once a year.

What exact local numbers of the four South Canterbury lizard species are is unknown.

Mr Frank's study identified that the local common gecko - in this area it is a distinct species of common gecko called the Southern Alps gecko - was mainly now in limestone areas in the South Canterbury hinterland whereas it was likely they used to be further down on the plains also.

Being nocturnal creatures, they were more difficult to spot and he had been unable to find out if geckos were cohabitating with skinks in stone rows on farmland.

At the time of Mr Frank's 2008 lizard study, which excluded the Mackenzie, it was not known what species he would find in South Canterbury.

The study identified four species, the common skink, the McCann's skink, the common gecko and the jewelled gecko.

His study had to work around the habits of the lizards, with skinks coming out to sun only in certain conditions.

Being cold blooded they used the sun to warm up, but would seek shelter from too hot conditions, leaving to hunt for insects among the stones. Where native shrubs are available, they will also eat autumn berries.

With conditions for sunning right, it was still possible to see quite a number, he said.

The McCann's skink was only found in one limestone area, quite separate from the other lizard species, and on two local beaches.

Although not widespread in this area, it was more common in the Mackenzie, he said.

"To have these remnant populations is quite important from a conservation aspect.

"If we can keep these habitats at least to a certain degree intact, so they can continue to live there, that's an important aspect of what we're trying to achieve."

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