Dr. Paul Auerbach is the world's leading outdoor health expert. His blog offers tips on outdoor safety and advice on how to handle wilderness emergencies.See all posts »
Great White Shark Adventure
Two weeks ago, I traveled to Guadalupe Island off the Pacific coast of Mexico to join a wonderful group of divers on a dive expedition aboard the M/V Nautilus Explorer to benefit the Historical Diving Society. The diving purpose of our journey was to photograph and video great white sharks underwater, and I'm happy to report that the adventure was a resounding success.
Led by guests Rodney Fox (the most famous shark attack survivor) and Zale Parry (the co-star with Lloyd Bridges of the television show "Sea Hunt"), the trip was arranged by Ed Stetson Diving and Charters. We met in San Diego, enjoyed a bus ride across the border to Ensenada harbor, boarded the vessel, and motored to our sheltered mooring adjacent to the coast of Guadalupe Island. Fortunately, there were few medical concerns, other than a bit of seasickness (which I will discuss in a subsequent post) and feeling waterlogged after spending nearly 20 hours underwater over three days. The latter was, of course, voluntary, and precisely the reason why this was such a fabulous expedition.
This was the second benefit expedition to dive with the white sharks at Guadalupe Island. All the proceeds from this trip were donated to the Historical Diving Society.
Guadalupe Island is a very remote island located 210 miles south of the Mexican border and 150 miles off the Baja Peninsula. The ocean voyage to reach the island was approximately 18 hours each way. On the way out, we followed a storm, so the beginning of the crossing was a bit bouncy, but over the course of the next 24 hours, the seas flattened out, so that we had calm waters for the shark cage diving, and a very smooth return crossing.
Guadalupe Island is 22 miles long and 8 miles wide. The island is home to about 80 people - primarily commercial abalone divers, lobster fishermen and their families. There is a very small school on the island for the 22 children. California sea lions, elephant seals and Guadalupe fur seals have rookeries on the island. There was no shortage of these animals, both on shore and swimming in the water, apparently oblivious to the danger lurking from below. Guadalupe Island was recently declared a Biosphere Preserve by the Mexican government. Passenger planes are no longer permitted to land on the island, so the only way to get to the island is by sea. It is now under the guidance of the Comision Nacional de Areas Naturales Protegides (CONANP). Sportfishing around the island is restricted and white shark diving is now well regulated. This protects the resources, the divers and the people who live on the island. Conservation is extremely important, because we know that shark populations worldwide have been decimated. It has been stated that the jaws of a great white shark sell for U.S. $30,000 or more.
Searching for Great Whites
There is a population of over 100 white sharks that live around the island. They range from about 12 to 18 feet in length, but a few juveniles have recently been spotted. They feed primarily on yellowfin tuna and an occasional seal or sea lion. In the winter, some of the sharks dive deep and travel to Hawaii. Others move to the mid Pacific at a congregation location, and others remain around the island. The migrating sharks return to Guadalupe around September. Various research programs are studying the white sharks at Guadalupe Island. It has been discovered that these sharks do not travel between the Farallon Islands and Guadalupe Island. The white sharks at Guadalupe are very curious, yet cautious. They don’t ram the cages as depicted on TV. However, we did have a few sharks nibble on the cages, and one juvenile shark flew from the water in its breaching behavior. Cage biting behavior is usually a result of pulling the bait directly toward the cage as the shark is chasing it. Great care is taken to not harm the sharks.
The M/V Nautilus Explorer was custom built in 2000 specifically for diving. The vessel’s homeport is Vancouver, British Columbia. We enjoyed a wonderful crew of 10 that included divemasters and 2 chefs. The Nautilus dives the summer in Alaska / British Columbia and works in Mexico during the winter: Guadalupe Island, Sea of Cortez and Socorro Island. The ship is 116 feet long and incorporates features not usually found on dive boats, including a very important hot tub. After being underwater in 70-degree F water for 4 hours at a time, I can vouch for how good it feels to gulp a few cups of hot chocolate while floating in the hot tub. You have to get that core body temperature up, so that you can get back in the water and not miss any of the action!
The weather was awesome, and the water visibility was excellent. It is typically between 70 to 120 feet in very blue water. We anchored in 250 feet of water about a quarter mile from shore. For the dive cage operation, there were three cages tied to the stern and another "boom cage" hung off the starboard stern. In addition, there was a cage that was raised and lowered on cable, for which we took turns diving to 40 feet, to get to another level and more sharks, often quite large. We saw a couple of animals that approached 18 feet in length.
In the Shark Cages
When I saw my first great white shark, it was pure excitement. When I saw my first 18 footer, it was like seeing a living locomotive. It is difficult to describe just how massive and powerful are these magnificent creatures. When they turn in the water, they bank like an airplane, and glide through the water with total mastery of the medium. There is no question that they reign supreme, more so than any creature I have ever witnessed.
Because we were standing in cages, we wore full wetsuits or dry suits, hoods, booties, gloves and a mask. To keep from floating, we wore heavy (40 to 50 pounds) weight belts or harness systems that allowed us to stand or kneel on the bottom of the cage. Air was pumped to each diver via a surface supplied hookah system with a second stage regulator. Emergency tanks and regulators were located in each cage.
The shark cages were specially designed for that purpose. Each cage could hold three divers, and they were constructed of schedule 80 steel. There were flotation tanks inside the top of the cages for added protection. The tops of the surface cages floated about 2 feet out of the water; the divers' heads were about 3 feet below the surface. We entered the cates through a door on the top then climbed down a ladder into the cage.
Viewing a shark from the boat deck was almost as amazing as viewing one underwater, because as we watched them glide around the cages, we could appreciate their massive size in comparison to the cages and comparatively small humans. I was fortunate to get a few wonderful photos and videos, which I will use for teaching purposes and entertainment.
For those of you interested in shark attacks, here is a brief bit of information, which was not needed by us during our trip to Guadalupe Island!
The jaws of some sharks contain rows of razor-sharp teeth, which can bite down with extreme force. The result is a wound with loss of tissue that bleeds freely and can lead rapidly to shock. Even if a shark bite appears minor, the wound should be washed out and bandaged, and the victim taken to a doctor. Often, the wound will contain pieces of shark teeth, seaweed, or sand debris, which must be removed in order to avoid a nasty infection. Like other animal bites, shark bites should not be sewn or taped tightly shut, in order to allow drainage. This helps prevent serious infection. The victim should be started on an antibiotic to oppose Vibrio bacteria (ciprofloxacin, trimethoprim-sulfamethoxazole, or doxycycline).The skin of many sharks is rough like sandpaper, and can cause a bad scrape. If this occurs, it should be managed like a second-degree burn, with antiseptic ointment and a dressing.
Tips to Avoid Sharks
If you wish to avoid sharks (which is not what we wished to do...):
- Avoid shark-infested waters, particularly at dusk and after dark. Do not dive in known shark feeding grounds.
- Outside of cages designed to protect you from sharks, swim in groups. Sharks tend to attack solitary swimmers.
- When diving, avoid deep drop-offs, murky water, or areas near sewage outlets.
- Do not tether captured (speared, for example) fish to your body.
- Do not corner or provoke sharks.
- If a shark appears, leave the water with slow, purposeful movements. Do not panic or splash. If a shark approaches you while you are diving in deep water, attempt to position yourself so that you are protected from the rear. If a shark moves in, attempt to strike a firm blow to the snout.
- If you are stranded at sea and a rescue helicopter arrives to extract you from the water, exit the water at the earliest opportunity.
None of this, of course, came into consideration during our adventure, because we were protected at all times and very cautious. Indeed, we all came away from our experience being much more committed to conservation and appreciating more than ever the wondrous nature of life in the wilderness. We must do everything possible to increase our understanding and support for preserving essential species like the great white shark.
photo by Paul Auerbach, M.D.
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