Swimming with Whale Sharks with Host Gregory Sweeney 2014
Not long ago, boat captains discovered the annual aggregation of hundreds of whale sharks (Rhincodon typus) off the coast of Isla Mujeres, a tiny little island off the Yucatan Peninsula in Mexico. I have been sharing this great event with guests and underwater photography for many years now and still find it a thrill and a grand opportunity for close up wildlife encounters. The whale sharks arrive in large numbers every summer to feed on the abundant supply of plankton and bonito eggs. For me it was an incredible experience to be in the warm blue water with these beautiful and graceful creatures. On several peak days hundred whale sharks would congregate in the space of a couple soccer fields. I have photographed whale sharks in locations around the world (Honduras, Mozambique, Western Australia), but never had the experience of being in the water with such a large aggregation and the large individuals who seemed unfazed by my presence. This year was another great year with numerous whale sharks and some giant mantas.Get Details of our 2015 Whale Shark Adventure
Our boats leave from Isla Mujeres, just a short walk or golf cart ride from our beachfront hotel. The 10 passenger boats are comfortable for our groups of 6 or 7 and they are fast, provide shade and storage, and smooth while cruising. Our boat captain and crew were excellent at finding whale sharks each day, sometimes just a short 40 minute boat ride. Sandwiches and snacks are on the boat with us so we are set to spend most of the day at sea. Regulations require we depart the whale sharks after 2pm, but this gives us plenty of time to enjoy our swimming. After long day on the water we would head back to Isla Mujeres but not before eating some ceviche freshly prepared while we were busy with the whale sharks. Once back at the hotel, we have a relaxing time in the hotel pool , a cleanup and download , and a delicious dinner out in town at one of many great restauants.
I schedule our trips in early July at the peak of season and durring the full moon since some experts say the food source (krill) peaks at this time. The weather was great with smooth water, great visibility and hundreds of whale sharks which were easy to find each day. For both our first and second week of guests, the water was clear and flat. Not even one day of bad weather or cloudy water! Very special.
On our second day, myself and crew a found schools of mantas. There were no whale sharks in the area, just the mantas. Like most days, we had this encounter to ourselves with no other boats near us. The mantas did their ballet of loops and plunges before moving off out of our range. It was time to return to shore so we came home very happy and content.
With the clear water each day, I tried some deeper dives, shooting up at the whale shark or manta. The result was a nice deep blue with a sharp, clear image of the whale shark presenting a contrasting foreground of white and light grey. I also like to photograph the feeding motion of the mounth from a 3/4 profile angle. The idea here is to capture the turbulance of the water as it flows into the mouth.
I use a Canon 5D MKIII in an Nexus housing for my underwater work. It is full frame and I like the quality video capabilities - I edited some videos together into a compolation video. Due to the size of the whale sharks I am using a Canon 15mm f2.8 fisheye lens. I looked at my shooting data in Lightroom from the full 2 weeks of whale shark swimming and most of the images fall into the below settings ranges.
|ISO||500 or 640|
|Aperture||f10 - f14|
|Shutter Speed||1/250 sec|
Back at the hotel we would relax at the pool for a while. One afternoon we tool the golf cart to the opposite end of the island where they have a zipline, a scenic park, and iguanas. There are many shops to pick up snacks and drinks. Each night we had a delicious meal at restaurants ranging from Mexican tacos to pizza, mediterranean, and cuban. After our 4 days on the whale shark boat, some of the guests returned to Cancun and did scuba dives in the Mayan cenotes and toured some of the ruins.
Swimming in this aggregation in the Gulf of Mexico was not like other times I have encountered whale sharks in other waters: we would hold in an area where there were 4 -5 visible then wait until they passed close and get in the water with them. They did not seem too agitated by our presence or the splash of our fins. I could swim along side one of them for a while then if they got ahead of me often they would turn and come back toward me. Waiting in one spot in the water often would put me in a good position to encounter another individual. We stayed in the water for hours at a time. Occasionally we would move the boat to keep up with the movements of the aggregation.
Whale sharks are the largest fish in the sea (5.5 to 10 meters and 20.6 tons average) and although massive in size, they are docile and fortunately for us they favor plankton over other food. As a filter feeder it has a capacious mouth, which can be up to 1.6 meters wide and can contain 310 to 360 rows of tiny teeth. The many rows of teeth play no role in feeding. Instead, the shark sucks in a mouthful of water, closes its mouth and expels the water through its 5 pairs of gills. During the slight delay between closing the mouth and opening the gill flaps, plankton is trapped against the dermal denticles which line its gill plates and pharynx. This sieve-like apparatus prevents the passage of anything but fluid out through the gills, trapping anything above 2 to 3 millimeters in diameter.
It is believed that they reach sexual maturity at around 30 years and their life span is an estimated 70 to 100+ years. A pregnant female whale shark can carry up to 300 pups 35 to 65 cm long which she gives birth to live. The spots on a whale shark's back are unique to each individual and can be used as a form of ID. In much of Latin America the whale shark is known as "pez dama" or "domino" for its distinctive spot pattern. In Africa it is known as "papa shillingi" from the Kenyan myth that God threw shillings upon the shark, which now has spots.