She disappears with the tide

In the Bay of Fundy, where the highest tides on Earth touch Canada's shores, a stunning new mural is naturally unveiled twice a day.

It's the latest work of surfing artist Sean Yoro, who has a penchant for precarious surfaces, having previously painted on floating icebergs, remote waterside walls and tree bark in a rainy forest -- always using eco-friendly paints.

This time he negotiated 28-foot tide changes while balancing on his board, creating a piece that is constantly transformed by the water level.

As long as it lasts, that is.

Vanishing canvas

"It was really challenging to adapt to the tide changes, from the dangerous rip currents to the quick rate of rising and dropping water levels, averaging 1 foot every 15 minutes," Yoro said in an email.

The tricky part of completing the artwork was having enough time to work on the lowest area of the wall, the first to get covered by the tide: "I had to be on a very strict schedule, knowing the exact levels of the tide every day and night."

The exact locations of Yoro's previous works were not disclosed, to avoid legal risks, but this time he revealed the mural is in Saint John, Canada: "I actually had the Bay of Fundy on my bucket list of places to paint long before Discover Saint John reached out to me with the idea to paint in their city," he said.

The city is across the bay from the Minas Basin, where the tide range can reach 52 feet, according to NASA.

Will it last?

Yoro uses nontoxic paint to minimize the environmental impact of his creations, which also gives his artwork an uncertain expiry date.

"When using eco-friendly paint, it is inevitable that the sun and saltwater will break it down with time," he said.

"Calculating the lifespan is very difficult because of variables such as sunlight and currents around the wall itself, but a safe estimate would have it lasting 2-3 months."

Yoro said algae could also be a problem and cover the bottom half of the figure, but there's a chance -- through a magical combination of excellent conditions -- that the mural could last up to two years.

Wet wall

Another problem was making the paint stick to a wall in very wet -- and rainy -- conditions: "It took a lot of experimenting with dozens of paints and sealers to come up with a special formula that would dry quickly enough and stay on the cement wall even when underwater for most of the time," Yoro said.

It took nine days to complete the mural, which measures 30 by 45 feet.

The unusually long time of completion was due to the rapid tide change, which limited the artist's access to the wall: "I had to use several calculated formulas to know the rate of the tides coming in or out every day, and use this information to know what speed I could paint for that tide change, which helped (me) pace myself in order to get the proper details finished in the figure."

"It was an incredible experience to witness this natural phenomenon and incorporate into my art."