Genome project could unlock mystery of feral flock

18:29, Jan 12 2013
The rare Arapawa sheep.
The rare Arapawa sheep.

Experts cannot rule out a rare flock of feral sheep found at Arapawa Island in the Marlborough Sounds coming from Spanish galleons landing in the 1500s.

Ranked as one of the wilder theories for the sheep's origins, if substantiated this would rewrite the history books with Abel Tasman credited as the first European explorer to discover New Zealand in 1642 and Captain James Cook circumnavigating it more than century later.

The common thinking was the sheep came from merino or merino-derived sheep from Australia, but this theory was ruled out by researchers tapping into a worldwide genetic project.

The sheep are unlike any other domestic breed in New Zealand.

AgResearch research associate Emily Young traced the sheep's closest relative to the Gulf Coast Native sheep, found in the southern United States of America.

This gives some credence to the galleons theory as the Gulf Coast Native sheep came from a mixture of Spanish breeds introduced in the 1500s.


However, the mystery of how they arrived in Marlborough may never be unlocked. Young said pursuing their identity more closely with more DNA work would be too costly.

She has been comparing the genetic tracing of pure- bred Arapawas to other sheep throughout the world in a project called the "Hap Map".

Ruling out the merino link had made their origins more interesting and added more to the Spanish galleon story, she said.

"It was quite exciting when we . . . saw there was an alternative because most people thought they were derived from the merino."

She said it was interesting to think that they came from a different breed.

Young said the remote possibility the breed was developed from a merino- northern European composite developing similar traits through natural selection could also not be ignored.

She said their origins may never be known.

"It's probably possible (to exactly trace them), but this is a much wider project and it's not something we would get funding for."

The sheep are mainly found in a feral state on the small Arapawa Island.

Young was 11 when her father brought some orphan lambs from a hunting trip in 1997. Her flock of Arapawa sheep, numbering 200, are sold to lifestyle block and hunting block owners.

Scientists working on the international genome project are creating maps which aim to show how time and local environments have changed the genes of sheep species.

The maps could become a key resource for researchers analysing genetic variations affecting sheep health, disease and responses to drugs and environmental factors.

Young was asked to provide samples from her Arapawa flock for the the "Hap Map" project.

Scientists are intrigued by the way the Arapawas adapted to island conditions.

Their hardiness and disease resistance could be important traits for farmers.

However, their smaller size and black fleece counts against them for conventional farming.

Young said the Arapawa sheep could have been in the Marlborough Sounds for longer than first thought.

The Department of Conservation had wanted to remove them to prevent them damaging the island ecology, but if they had been there since the 1500s, it was safe to assume they had been happily co- existing, she said.

The Press