SCUBA diving and snorkelling are amongst the fastest growing tourism sectors. The increasing numbers mean many more people are aware of the beauty and importance of the marine environment, but also puts a great strain on the coral. Not only is it damaged by inexperienced divers kicking it and pollution from boats and hotels, research also shows that coral is much more likely to become diseased in highly dived areas.

Lionfish, genus Pterois, is very popular amongst those with aquariums, and this trade may have led to them being described as amongst some of the most aggressively invasive species on the planet. Lionfish are native to the Red Sea, Pacific Ocean, and Indian Ocean, most often found around corals, reefs and rocky surfaces down to about 50 m. They have quite a distinctive appearance with their red and white stripes, together with large spiky dorsal fin rays containing venom for defense against predators. They don’t appear to have many natural predators, but large Groupers and Moray eels have been observed feeding on them.

from Undercurrent Magazine

The GoPro Hero range of action cameras is a marvelous addition to your dive gear bag. I first wrote about GoPro and its Hero3 model in the November 2013 issue of Undercurrent, but in its latest Hero 4 incarnation with its watertight housings, these little POV cameras have an application for almost any activity, especially risky activities that might destroy a more conventional camera. No wonder GoPros proved to be the most popular Christmas present of 2014.

The Underwater Photography Guide is now accepting entries for the 5th annual Ocean Art competition. Prizes worth over $75000 are on offer in 15 categories giving underwater photographers of all levels a chance to win.

For the less experienced photographers there are novice, compact camera and mirror-less camera categories. Then there are the wide-angle, macro, marine life portraits and marine life behaviour. More unusually, this competition also features categories of supermacro, cold or temperate water and nudibranchs.

Imagine it’s your job to dive for scallops deep in the cold, murky waters off the Maine coast. It’s a hard job and one that fewer fisherman are doing.

Now imagine you have use of just one arm. That’s the case for James Sewell, who lost his right arm in a 2009 snowmobiling accident and resumed diving less than a year later, according to this New York Times video by Maine filmmakers Christoph Gelfand and Caroline Losneck.

“I’ve never been a person that likes for people to do stuff for me,” said Sewell, who also dives for urchins and fishes for bluefin tuna. “I like to do for myself.”

According to the Times, Sewell, 43, is one of only about 30 active scallop divers working on the Maine coast.

The video shows what that job is like for Sewell, who dives off his boat, the Sophie Elizabeth, out of Cushing.

“It’s just not a 9 to 5 job. Deep diving puts a lot of nitrogen into your blood. It’s hard on your joints. It’s hard on you,” Sewell says in the video. “Once you get to a certain age you’re not going to be able to keep doing it. I think about my family and the risks you take. Every day that you go down on bottom you have that chance of something fails or something happens — that might be the last time that you see them.”

It turns out that blindfolding a shark or plugging its nose isn't enough to deter it from going after prey. When a shark gets hungry, it will use all the senses it has available to hunt down something to eat, a new study reveals.

The goal of the study was to figure out how sharks use their different senses together, rather than isolating one sense at a time. Researchers examined three species of sharks — blacktip, bonnethead and nurse sharks — in an artificial flow channel inside the Mote Marine Laboratory in Sarasota, Fla.

At 9 foot long, not including the tail, tiger shark (Galeocerdo cuvier) Harry Lindo is not exactly on the small side.  It’s not Harry’s size that is exciting scientists and shark enthusiasts, nor a photograph taken in 2009 by Ian Card showing a shark – suspected to be Harry, trying to eat a 150 lb juvenile tiger shark off the coast of Bermuda.  Between 2009 and 2012 researchers tagged 24 tiger sharks with satellite transmitters in the Challenger Bank, which lies just off Bermuda in the Atlantic Ocean.  In study lead by James Lea (The Guy Harvey Research Institute, Nova Southeastern University Oceanographic Center) and team of international collaborators, those shark movements have been compiled and analysed.  Harry, it turns out, is one heck of an ocean wanderer.  In just over 3 years Harry swam over 44,000 kilometres – that’s more than the circumference of the Earth (just over 40,000 kilometres).  Harry’s track is the longest recorded for a tiger shark, and probably the longest ever published for any shark species.

Since I’ve scuba dived as many times as I’ve bungee jumped in a leotard (not very many, if you’re wondering), I took a deep breath and tapped three regional experts for tips on where to go in Canada – starting with Russell Clark from the Dive Industry Association of British Columbia.

A little more than 238 years ago, our forefathers used the best technology available to inspire colonial proto-Americans to revolt against the King of England. At that time, the “best” technology available was the printing press and the “best” social network required the use of “word of mouth” in Public Houses. Grog (small beer) was the lubricant that facilitated this communication and the rest, as they say, is history.

But while all this was going on, there were a bunch of entrepreneurs and a few startups that changed the world. In the 1770s, America was a relatively low tech, agrarian society, but as you can see from the list below, all that was about to change. So here, for your Independence Day reading pleasure, are the seven hottest tech trends circa 1776.

A few years ago, Italian farmer Luca Gamberini began pondering what it would take to grow perfect garden vegetables. He already knew that plants need constant temperatures, as well as water, light, and protection from harmful external elements. But since it can be difficult to recreate these conditions outdoors all year long, or even at all, Gamberini needed an alternative that could provide a more stable growing environment.

His solution? Underwater greenhouses.

You don’t usually find a wireless network whilst underwater, but that may change as researchers at the University at Buffalo are developing a deep-sea internet. They hope that this technological breakthrough will lead to improvements in tsunami detection, pollution monitoring and other activities.

What makes your book different from other books about diving around the world?

There are two principals we have stuck to ever since the first edition. Right from the start, we asked other divers where they had been and where they were diving next. And then we focused on those places people actually want to go to and can afford to go to. Let’s face it, we would all love to dive the Antarctic, but few of us will win the lottery this week! The other thing is that we can say – hand on heart – that there is nothing in the book that we haven’t personally done. If we haven’t dived the country or a specific site, we don’t write about it or pass opinion. It makes the guide unique. Yes, it is personal to us and our experiences but at least readers know we have said it because we have done it!

Blue ringed octopus

Popular diving locations tend to be centered around marine biodiversity hotspots. The unique landscapes of coral reefs and mass congregations of marine leviathans draw divers like prey to a frogfish lure. These same spots usually have a history of local livelihoods like fishing, and few locations exist where there is no conflict between these two industries.

Marine Protected Areas (MPAs) are parts of the ocean where certain activities are restricted benefit both divers and fishers, creating a permanent pool of marine resources that then seed and replenish heavily used areas.

The term "Marine Protected Area" is an umbrella term, and may refer to a variety of regualations and restrictions. Unfortuantely, a misunderstanding of the rules and regulations that surround MPAs can lead to a volatile relationship between the diving industry and other local livelihoods using reefs and other ecosystems. Here we cover some useful tips that you can use to promote these fantastic resources for more collaborative efforts for protecting valuable marine life.

Massachusetts Institute of Technology (MIT) researchers have demonstrated an untethered miniature origami robot that self-folds, walks, swims and dissolves. From a flat 2D sheet with a magnet on it, the robot folds itself up in a matter of seconds, zips around via magnets on land or water and then gets dunked into a tank of acetone to dissolve completely.

SS Gairsoppa: The Gairsoppa lies approximately 3 miles below the surface of the North Atlantic Ocean. The ship sank after being hit with a torpedo on February 17, 1941. Odyssey discovered the shipwreck in 2011 and inspected the site with a remotely operated vehicle (ROV). What appear to be tea chests were observed in one cargo hold that was accessible to the ROV. The Gairsoppa’s cargo manifest included more than 1700 tons of tea and research indicates the ship was also carrying up to 7 million ounces of silver.

SS Mantola: The SS Mantola lies approximately 1.5 miles below the surface of the North Atlantic Ocean. The ship was less than a year old when it was hit by a torpedo on February 9, 1917 and sank. Odyssey discovered the shipwreck in 2011, approximately 100 miles from the SS Gairsoppa shipwreck. This video was taken during the inspection of the site with a Remotely Operated Vehicle (ROV).

HMS Victory: Balchin's HMS Victory was the predecessor to Nelson's Victory. It was commanded by Admiral Sir John Balchin and was considered the greatest ship in the world when it was lost. In a storm in 1744. Armed with up to 110 guns, Victory was the last Royal Navy warship to be lost at sea with a complete complement of bronze cannon. The shipwreck was discovered in 2008 by Odyssey Marine Exploration.

SS Republic: Scenes from the SS Republic shipwreck site, a Civil War era paddlewheel steamer which sank approximately 100 miles off the Georgia coast. Odyssey recovered more than 51,000 coins and nearly 14,000 artifacts from this site 1,700 feet deep.

HMS Sussex: Underwater video from a shipwreck site believed to be HMS Sussex, a British warship which sank in 1694. The video was taken during pre-disturbance and core sampling surveys at the site.

"Tortugas": This Spanish colonial shipwreck discovered approximately 1500 feet deep was the first ever deep-ocean remotely-operated archaeolgical excavation. During the 1990-1991 excavation nearly 17,000 artifacts, some as small as seeds and pearls, were recovered

"Blue China": Likely the remains of a modest American coastal trader conducting business along the Atlantic Seabaord in the years preceding the American Civil War.

Hermit crabs scuttle about the sea-floor using someone else’s
shell for a home. They always use empty shells and never
kill the original occupant.