Kill a rare animal to help preserve it? That's the plan in New Zealand, where a team of hunters will soon go out to collect a few critically endangered Arapawa Island boars, a breed that only exists on that tiny island. Their plan is to kill two pigs, then extract their semen for later research.

The Arapawa Island pig breed was introduced to the island in the 19th century by visiting whalers and exists nowhere else in the world. It almost went extinct in the 1990s, but four healthy piglets were captured from the wild and formed the core of a small mainland breeding program. Now, with other pig breeds also being introduced to the island, the Arapawa breed faces competition that could eliminate its precariously tiny gene pool.

Michael Willis, head of the Christchurch-based Rare Breeds Conservation Society's expedition to capture the pigs, told Wellington's The Press that semen has never been extracted from dead pigs, and if it's successful, it could lead to methods of preserving other rare breeds.

Why are the Arapawa Island boars' genes important? They might not be, but scientists point to another rare breed, the Auckland Island pig, whose cells are being used in a trial to cure diabetes. If the Arapawa breed goes extinct, we'll never know if their genes have some value, medical or otherwise.

Here's another question: Why do the pigs have to be killed to extract their semen? Ten seconds of Internet searching shows that there seem to be plenty of techniques out there for extracting boar semen without killing the animals. (I'll admit, the phrase "pig semen extraction" is one I never thought I would google.)

The expedition, which will launch October 25, also aims to collect a few sows (females) to add to the breeding group on mainland New Zealand.

Arapawa Island is also home to a rare breed of milk goat, another introduced species, which is now extinct in its native England.

Photo: Arapawa Pig via the Rare Breeds Conservation Society of New Zealand