Martin Gray may live 4,300 kilometres from Halifax, but the Orkney Islands, Scotland, resident has come to learn a bit about Nova Scotia through his hobby of beachcombing.

While he's been beachcombing for most of his life, the 51-year-old has been documenting his finds on social media for two years and that's been helping him gain insight into what he finds as people share information about his discoveries.

"There's a lot of nonsense on Facebook and Twitter. There's a lot of rubbish. There's a lot of kittens and people's dinners, just nonsense, but for getting to the bottom of a story, social media is just wonderful," he said.

Through social media, he's been able to learn the origins of Nova Scotia finds like lobster tags, an inflatable buoy from a Shag Harbour fishing vessel and a float from a Woods Harbour boat.

"Beside me right now is a milk crate from the Scotsburn dairy, which I gather is a very famous dairy product outlet in Nova Scotia," said Gray.

Gray says tags from Nova Scotia lobster fishing areas 33 and 34 are a common find he makes. (Submitted by Martin Gray)

When he notified Scotsburn officials about his find, he said they graciously told him he could keep it.

Gray credits his late father for instilling a love of beachcombing in him. He said his dad was brought up in the Second World War years and with scarce resources, it demanded families be resourceful and reuse and recycle, which is a trait that's been passed on to Gray.

While this is one reason he beachcombs, another is that he does it as a means of tidying up the ocean, which is littered with plastic.

The distance between Halifax and the Orkney Islands in Scotland is about 4,300 kilometres. (Google Maps)

A 2015 study estimated that eight million tonnes of plastic enter the oceans every year. The source of much of this plastic is unknown. It includes abandoned or lost fishing gear and illegally dumped waste, but the largest source is likely garbage and debris carried into the ocean from land.

Plastic is regarded as a "persistent pollutant" because it doesn't go away, said Dalhousie University marine biologist Boris Worm.

"There's a lot of things you put in the ocean that break down over time and plastic does, but over [a] very, very long period of time. A plastic bag may last as long as 500 years or more, a diaper about the same, a plastic bottle even longer, so these things accumulate in the ocean," he said.

A 4,300-kilometre voyage

The items from Nova Scotia that end up in the Orkney Islands make their way across the ocean thanks to the currents in place.

Martin Gray, 51, has been beachcombing for most of his life. (Submitted by Martin Gray)

"The myriad of minor currents and eddies off the coastline of Nova Scotia would slowly move a floating object east toward the Gulf Stream," said CBC meteorologist Kalin Mitchell.

"The Gulf Stream then becomes part of the North Atlantic Current as it crosses toward the U.K."

He said there's a branch of the North Atlantic Current that extends north of Scotland, which is called the Norwegian Current.

Mark Mallory, a biology professor at Acadia University in Wolfville, N.S., said plastics add another challenge to the lives of marine species that are already threatened by things like warmer and increasingly acidic oceans.

He said plastics are particularly dangerous for wildlife that mistake it for food. If the plastic is sharp, it could perforate their internal digestive tract. For adult birds that bring food to their young, plastic can be especially problematic.

The Nova Blue is a vessel from Woods Harbour, N.S. (Submitted by Martin Gray)

"They can cram so much into them that effectively all of their digestive space gets taken up," said Mallory, Canada research chair in coastal wetland ecosystems.

"They can starve to death because there's no room left in there for them to effectively digest real food because it's all filled with plastic or alternately they can choke to death."

'A nail in the coffin of the oceans'

Mallory said plastics can also attract contaminants that move through the air or the ocean.

"Other types of contaminants absorb to those plastics, so effectively the plastics kind of piggyback around chemicals," he said.

As for the fishing gear Gray recovers, he said he doesn't believe fishermen are "callously and carelessly and thoughtlessly polluting the seas."

But he has a plea for people to be more mindful.

"Please dispose of your plastic with a conscience," he said.

"Think about it, don't just chuck it ... it's a nail in the coffin of the oceans and the life therein."