Father of pearls

Updated

Why one man's pearl nursery is perfectly placed on the remote Abrolhos Islands.

There is something in the water off the Abrolhos Islands.

At first glance, operating an aquaculture hatchery 60 kilometres out to sea on a small island with no running water or power and minimal infrastructure just does not add up.

Everything at this shellfish hatchery off Western Australia's mid-west coast is powered by generators, which must run without fail to ensure the pumps, lights and air conditioning operate 24 hours a day, seven days a week for months on end.

If a pump or generator breaks down, a replacement has to be sent by plane or boat from the mainland.

It can be a huge risk to the survival of the billions of blacklip shell larvae being grown by Murray Davidson.

So why build a hatchery on these remote islands?

"The water is so clean and pristine out here. Anything will grow if you do it right," he said.

Science and nature combine

In years gone by, the islands hosted guano mining; nowadays, a fleet of rock lobster fishers remain.

A combination of the warm Leeuwin Current and the islands' isolation from populated areas and industry allows them to stay relatively untouched and clean.

Mr Davidson pumps sea water straight into his hatchery, ensuring the larvae have the best opportunity to survive and grow into shellfish for the pearling industry.

He says changing the water daily is like changing paddocks for livestock on a farm — an important process to flush out waste and replenish the environment in which the larvae feed and grow.

But it is not just the pristine water that ensures his success.

There is a great deal of proven science behind it, according to Derek Cropp, a hatchery expert from Tasmania who has worked with Mr Davidson on and off for 25 years.

"Murray's hatchery on Rat Island may look primitive, but there is actually a lot of innovative technology," he said.

The pair work to find and grow the best food source for the larvae, which are grown for 30 to 35 days before turning into spat — oyster larvae that has attached to the shell.

During this time, Mr Davidson keeps a keen eye out for the "shell leg".

When a leg appears out of a shell, looking for a place to settle, that is the point when larvae have become spat.

They will be held for another 60 days before they are sent out to pearl farms across the islands.

The farms take the spat and monitor them for two years before adding the nuclei to produce the pearl.

Even then, it is not guaranteed that every shell will produce a pearl. Some may not have been placed in the shell properly or the shell has rejected it.

There's a further four to five-year wait for the shell to produce a black pearl.

The pearl pantry

Mr Davidson's algae room is his pride and joy.

It is the heart of the operation where he grows five different species of algae to feed the larvae.

It has taken him years to get the mix right to ensure the larvae survive, but it was not always that way.

He recalls building his first hatchery in 2008 at Coronation Beach, just north of Geraldton, where he produced three million spat in the first year — a good result.

In the following three years, however, he produced zero spat.

Mr Davidson said it took him all of those years to work out why his larvae were dying.

"I remember Wayne O'Connor [of the NSW Department of Primary Industries] said to me once: 'You can't call yourself a hatchery until you've killed a billion.'

"Well, I've well and truly surpassed that number."

It was a long, tough journey, and Mr Davidson recalls a lot of trial and error. But he kept persevering.

Chance discovery

Mr Davidson comes from humble beginnings. He did not finish high school, and he vividly remembers his headmaster saying to him that he would be dead by the age of 21.

He left school in year 10 and turned his hand to shearing. It was during this time that he recalls learning about hard work and perseverance.

"I learned that working hard was a way to achieve greater things," he said.

These days, he works mostly at sea but still loves to shear when he can.

"My wife says, 'I didn't marry a shearer'."

Before turning his hand to pearling, Mr Davidson worked on oil and gas rigs and fished for lobster.

He remembers the day he found a blacklip shell at Abrolhos which showed him they grew naturally in the area.

He knew the shell could be used to grow black pearls, and together with mates Alf and Don Woodcock he pushed for a pearling licence in 1998.

Developing tourism

Along with the blacklip shell, Mr Davidson is growing penguin shell as a meat source to sell to restaurants.

Add to that plans to also hatch koi shell, scallops, sea urchins and sea cucumbers — everything is found locally.

It means it is a good environment for the species to grow and nothing that could upset the ecosystem is introduced.

But Mr Davidson is also keen to develop tourism on the islands, for people to come out and see what he is doing.

"There's more than just crays out here."

He sees a future when charter boat groups visit the island and see how pearls are grown, before perhaps buying some to take home.

"Blokes will come out on five-day fishing charters and they might arrive here on the last day, and because they're feeling guilty leaving their loved ones behind, they might pick up a pearl to take home to them."

Topics: marine-biology, fishing-aquaculture, animal-science, environment, science-and-technology, people, human-interest, houtman-abrolhos-6530, geraldton-6530

First posted