Imagine seeing 150 dolphins leaping straight towards you through the waves, or spotting minke whales, or observing massive leatherback turtles and sunfish, writes Martin Hesp.
It's all in a day's work for Paul Semmens, who must have one of the most unique jobs in Britain.
It is Paul's job to sail aboard the Scillonian III at least once a week in summer to make a scientific survey of all he sees in what is a particularly lumpy bit of ocean.
This season has been the most successful since he started making the regular trips on behalf of both the Cornwall and the Isles of Scilly Wildlife Trusts four years ago.
The marine wildlife guide has spotted harbour porpoise; common, bottlenose and Risso's dolphin; minke whale; leatherback turtle; basking shark and ocean sunfish.
It's a job that might sound like heaven on earth to some – but others know the crossing between Penzance and the Isles of Scilly can be notoriously rough.
Paul said: "I don't get seasick – touch wood. On the way out, the crew announce I'm on board and I talk to passengers, pointing out birds and so on.
"On the way back I go on the bridge and do a scientific survey.
"During the four years I have worked on board, 2012 has been my best yet. There was a huge increase in harbour porpoises, a species that is not easy to spot in all but the calmest conditions.
"There has been a definite inshore movement of this species, as well as common dolphins, probably in response to shoals of small bait fish.
"It was great to see leatherback turtles – they are huge beasts that can grow to seven feet long.
"It has been a record year in Cornish waters for this species.
"As we approached autumn we had regular sightings of minke whales and Risso's dolphins – especially as we drew near the Isles of Scilly. I would like to thank the crew and Isles of Scilly Travel staff for their continuing support."
And Paul's favourite maritime sight of the season?
"We were just past Lands End and suddenly 150 dolphins came jumping straight towards the boat."