Diver and environmental activist Scott Cassell will set out from California's Catalina Island today in a bid to swim 30 miles underwater to Los Angeles. He'll be supported by a team that will include a film crew shooting the adventure in high definition 3-D.


Scott's dive is being made (with sponsorship by Luminox) to bring attention to the decline in shark populations in the waters where he's making his dive. Scott is actually bringing an acoustic shark attractor to maximize the number he comes across. Twenty-five years ago, the shark population in the Catalina Channel was thriving, and Scott estimates that he would have seen 40 to 100 blue sharks had he made a similar trip back then. He thinks he'll be lucky to come across more than a couple on his swim today. Let's hope he's wrong.


You can learn more about his attempt over at Luminox and the Undersea Voyager Project site.


Scott kindly agreed to take some time out of his pre-swim preparations earlier this week to answer some questions for us. Enjoy!


And good luck today, Scott!


MNN: What kind of logistical planning goes into preparing for a 30-mile dive? 

Scott Cassell: My team and I have worked in unison with five boat crews, more than 25 volunteers, the Catalina Island Marine Institute, the Cabrillo Marina, and many sponsors to bring this together. With a dive of this length, all equipment must be checked and double-checked to ensure not only my safety but the safety of all support divers, underwater camera operators and mission support crew members. Careful calculations have been made taking into account water temperature, currents, probable White shark strike zones and weather.


Each crew member, boat and volunteer must be assigned a specific duty and place. All boat captains receive Vessel Mission Specific sheets in order to coordinate who and what needs to be where and when. It takes an incredible amount of planning and flexibility among participants, but we have no egos here. Everyone is willing to do whatever it takes to make this a success. After teaming with Global Reef, who agreed to document the effort we were able to relax a lot in that area because they are exceptional film makers.


How do we save sharks? What needs to happen? 

In simple terms ... we need to stop eating shark and, more specifically shark fin soup. Experts estimate that these animals are slaughtered at a rate of 100 million a year. Sharks have survived as a species for literally millions of years. With our modern fishing techniques and growing global population, we have begun the process of wiping them out in one or two generations. I propose a world-wide ban on shark fishing of any kind.


What scares you most about the ocean? 

What scares me the most are the changes taking place in the chemistry of the ocean. Much of the planet's oxygen is generated from the ocean. Even a slight change in that delicate chemical balance, regardless of cause, and we change the very air we breathe.


Phytoplankton is the building block of all life on Earth. We can't afford to ignore the changes taking place there. Also, the imbalance created in marine life by man-made slaughter and carelessness should be enough to keep anyone awake at night.


What is the biggest challenge to pulling this off? 

First it was raising enough money. We started on Kickstarter.com and were successful. We were also fortunate enough to get a grant from The Roddenberry Foundation and, of course, Luminox has been behind this all the way. After that it became a matter of gathering and checking all equipment, including designing and building our own dive bell.


In something like this it is also important to spend time establishing solid relationships with those involved. I've spent a lot of time just meeting with people, listening to them express their love for the ocean and the heartbreak of the change they've witnessed in their lifetimes. They are not here for fame. They are here to help. It's been an honor to work with every one of them. The last great hurdle has been to get the word out while designing a schedule for a large crew. We're still working on that and will probably be making changes and adjustments until the last minute.


What are the biggest changes in the ocean that you've personally seen since you first started diving? 

The huge rise in the population of Humboldt squid is scary. I've been studying them for many years. Tuna and shark are their natural predators and are important in keeping the populations down. Each Humboldt squid female is capable of having millions of babies. Even with a small percentage of them reaching adulthood, they can devastate fisheries and feeding grounds due to their voracious appetite and ability to adapt to different depths and temperatures.


Without their natural predators keeping them in check, they are becoming like locusts, swarming and devouring. I've also seen subtle changes that denote huge problems. Changing structures in coral are just one example. There are too many of these changes and the balance is tipping. How long before it's irreversible? We can't afford to guess ... we have to find answers and act responsibly as a global population.


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