SURROUNDED on all sides by mist that melted almost imperceptibly into a rolling grey horizon and squinting into belts of particularly bracing North Sea wind, my hopes of spotting anything more exciting the occasional whirl of sea-kelp were not high.

Binoculars at the ready and cagoule zipped up to my chin I was on deck and on the look-out for dolphins, porpoises and whales during a three-day DFDS wildlife mini-cruise between Newcastle and Amsterdam.

As we made our way to Ijmuiden I was optimistic, but to my mind dolphins are more suited to shimmering aquamarine waters and white-sand beaches – surely not the gun-metal depths of the North Sea.

But minutes later, a fluttering off the starboard bow gave way to two dolphins emerging from the wash.

The white-beaked dolphins, identifiable by the white flashes behind their dorsal fins, leapt through the waves for just a few exhilarating seconds, keeping pace with the boat before submerging once more.

And this was not a one-off occurrence, since March this year observant souls on the DFDS King Seaways ferry have recorded 166 sightings of white-beaked dolphins, 17 of bottlenose dolphins, 14 sightings of seals and a massive 246 sightings of harbour porpoises.

For the last nine years wildlife officers from marine wildlife charity ORCA have been working on board DFDS Seaways ferries.

Between April and September, volunteers sail the wildlife-rich waters of the North Sea, monitoring marine mammals and identifying whale and dolphin habitats.

The monitoring data collected by ORCA helps to define the conservation status of whales, dolphins and porpoises in our waters.

The information is also vital in the development of important conservation projects for marine mammals.

The wildlife officers and volunteers also work from their on- board ORCA centre to engage with passengers and inspire renewed respect for safeguarding marine habitats.

As well as leading daily deck watches, the officers offer children’s activities and information sessions on marine wildlife and conservation.

Volunteer Becca Reed has been working with ORCA for five years, taking part in offshore surveys in her free time.

She said: “I work in an office; it’s not the most glamorous job and I’ve always loved dolphins so I thought, why not volunteer.

“I love interacting with people and seeing the kids’ faces when they realise there are actually dolphins in the North Sea.”

Despite their numbers, porpoises are notoriously more shy and nervous of the noise of the ship’s engine than dolphins.

And when a porpoise was spotted just minutes after I left the deck to shake the salt water out of my hair, I became ever more determined to spot one before returning to British shores.

So as we set sail for home, after a sunny five-hour sojourn in Amsterdam, I positioned myself once more on the observation deck as diving gannets wheeled hopefully overhead.

I was joined by Becca and ORCA wildlife Officer Will Matthews, who was keen to spot the elusive minke whale before his month-long placement ended.

The smallest of the rorqual whales, minke whales, are unpredictable in their behaviour and had only been sighted eight times from the boat this year.

Will said: “We do spend a lot out time out here on deck in all weather, looking at a grey sea and if you don’t see anything, you can feel quite despondent.

“But when when you do see an animal jump up from the water, it gives you this sense of a tangible connection to their world.

“Marine mammals seem to capture people’s imagination; they’re one of the few mammals we can see in their habitat and have that connection with.”

Sadly, the minke whales stayed away during this voyage, but leaving Ijmuiden, excitement bubbled up once more after the signature small black dorsal fin of a porpoise was spotted.

l DFDS Marine Wildlife mini-cruises are available until September 13 and include two nights’ accommodation on board and transfers from Ijmuiden to Amsterdam.

For more information, visit www.dfds.co.uk.