This episode screened May 26, 2007.
Every December a dozen or so members of a local extended family take a boat to an island off the tip of the Mahia Peninsula - but it's not to take a relaxing holiday.
Portland Island's only year-round residents are 1000 sheep - and the Spark family's mission is to round them up, drench and shear them.
The island was once inhabited and even had a small school - some of the current family members spent their childhood there.
Today the only signs of habitation are a basic accommodation
unit and the old woolshed.
When the family sets out for the 20-minute trip to the island, they have to take everything with them for a week-long stay - quad bikes, dogs, shearing equipment and temporary fences for the sheep-yards.
They also take along basic food but supplement it with a ready supply of fish and crays that can be caught around the island.
The island's rugged terrain makes mustering a tough job.
In charge is Alf Spark, the farm manager on Onenui Station, just across on the mainland. Helping him is his brother Ralph, along with a group of adult children, nieces and nephews from the next generation.
Once the shearing's finished, they ship 500 lambs back to the mainland, all ferried on a tiny barge - but moving the lambs creates an additional problem.
Portland Island is one of only two places in New Zealand where Cape Tulip grows - the other location is in Fiordland where the plant isn't a problem. But in the Mahia area it's a noxious weed and seeds could be carried in the lamb fleeces.
The lambs are first confined to the beach and yarded into a pen on the shoreline, then carted to the woolshed to be shorn. The wool will be kept separate and sent to a scouring plant to kill off any Cape Tulip seeds.
Watch exclusive video from this episode:The Country Calendar crew used a helicopter to get aerial shots of Portland Island. To see some of their shots that aren't in this week's TV programme, plus footage of the shearing party travelling across Onenui Station on their way to the island click on the related video link above.