Questions have been raised over a three-week mission to locate and re-home three native skinks, at a cost of $85,000.

It involved clearing vegetation along State Highway Three near New Plymouth - and releasing one copper skink and two gold striped geckos at Everett Park Scenic Reserve.

Auckland University conservation biologist James Russell says the money spent was a fraction of the total costs of work on the highway.

He explained New Zealand is extremely bio-diverse - and gold-striped geckos are incredibly rare. 

"It's just another species where we don't know what's happening - and if we don't look, it'll just disappear and be another blot on our record."

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