Husband and wife spider specialists Ray and Lyn Forster relax for a moment before the formal launch of their new book on spiders last week.

By John Gibb

Some New Zealand spiders catch fish while others use unusually large eyes to outstare their rivals.

Other spiders "balloon" great distances, travelling by air after emitting gossamer threads which are caught by the wind.

The male of another New Zealand spider species, found in Central Otago, uses silky threads to lash its female partner to a leaf before mating.

A mass of such apparently unusual and fascinating behaviour is revealed by Dunedin spider specialists Dr Ray Forster (77) and Lyn Forster (74) in their latest spider book, Spiders of New Zealand and their Worldwide Kin , which was formally launched at the Otago Museum yesterday.

In 1973, the Forsters wrote what was then the most comprehensive New Zealand spider book, Spiders of New Zealand .

At that stage, only 500 of an estimated 2500 New Zealand spider species had been described.

Their latest spider book, published by the University of Otago Press, includes a further 800 species, most of them named and described by Dr Forster.

Fear of spiders deprived many people of the chance of learning more about them, Lyn Forster said in an interview yesterday.

However, caution was appropriate, given that a few species were poisonous and some others could inflict a bite in self-defence, if disturbed, she said.

Many people had a positive attitude towards spiders and hundreds of people wrote to the Forsters with interesting observations, sometimes providing specimens.

The "black widow spider", related to the New Zealand katipo and famous for allegedly eating its male partner after mating, was no more dangerous to its mate than female spiders of many other species were to theirs, she said.

She acknowledged that the male of one spider species, Diaea ambara , had been seen tying its partner to a leaf before mating.

It was unclear why this was done, including whether it was an effort to avoid becoming lunch, she said.

Also included in the book is a yet to be described form of New Zealand water spider, called Dolomedes sp., which walks on water and catches small fish, mainly cockabullies, that swim beneath its feet.

Dr Forster, who was director of the Otago Museum from 1957 to 1987, said yesterday he remained as passionate about New Zealand spiders as he was when first introduced to the subject at the Dominion Museum, Wellington, in 1941.

Such creatures provided an intriguing glimpse millions of years back in time to when New Zealand was part of the Gondwanaland super-continent, he said.

Thursday, 2-December 1999