For more than 15 years Wade and Robyn Hughes have spent part of each year travelling the world photographing whales.
The Perth couple's amazing encounters are documented in a new book, Looking for Whales, with incredible images capturing the lives of the giants of the sea.
Wade, 71, and Robyn, 64, have been married 41 years and have the perfect arrangement: Wade does all the underwater photography with just a mask, snorkel and fins, while Robyn records what is happening on the surface.
"Occasionally when Wade comes up and tells me what he has seen I wish I could get down there too, but he has a better eye under water than I do," said Robyn, also a diver.
"The best thing is the excitement and experiencing nature up close and personal in a way many people don't get to do."
The book immerses the reader in the world of these mysterious creatures, combining evocative black-and-white images with text by Wade providing background and insights.
It is an extension of the couple's successful 2017 photographic exhibition at Fremantle's Kidogo Arthouse gallery.
The retirees' first adventure was in 2005 to the Azores Islands - a group in the North Pacific Ocean 1600km off Portugal - to get into the water with sperm whales.
"We were lucky on the first expedition to have some great encounters. They are fascinating animals," Wade said.
"Our experience has evolved over time. The very first sperm whale I swam with was a bull as big as they get, 18 metres long and 50 tonnes.
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"I don't have a photo of it. I was carrying a camera, but all I could do was stare at it.
"As it went past, I made eye contact and realised it knew I was there. It maintained its course and... swam off into the haze and I was just left staring into the blue.
"It has evolved from that: from being unable to take a photograph to actually being able to observe and capture what I am observing."
The adventurous duo have captured whales breaching and diving, meeting, greeting and communicating. Most memorably, they sat in their boat surrounded by 50 whales as one gave birth.
"We charter a small inflatable boat so we are very close to the surface," Robyn said. "It's a wonderful feeling of freedom being 20 to 30 kilometres out on the ocean.
"We are always aware we are in the water with a wild animal that roams the sea. We never touch them: our job is just to record them.
"Sometimes we have seen the same whales from one year to the next and that is always a good feeling."
All the couple's photos are available free to students to assist them in studying whale behaviours.
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