Photo of the Week: May 11, 2009

Hi Gang!

No matter how long ago they occurred there are certain times in our lives that stand out so vividly in our memories that we feel like are re-living the moment whenever we think about it. We can remember exactly where we were, who we were with, what we were doing and wearing, and how others around us reacted to the events as they unfolded. For me, those moments include a number of widely ranging events; President Kennedy's assassination, the Berlin Wall coming down, my beloved Razorbacks winning college football's national championship in 1964, the Milwaukee Braves winning the World Series in 1957, Hank Aaron hitting home run number 715, and a few first kisses etc.

Lucky me, I can also add a magical afternoon spent free diving with feeding whale sharks in La Paz Bay in the fall of 2005. I was diving from the Solmar V with Steve Ando, Bonnie Pelnar, Jim Watt, a wonderful friend and photographer from Kona who unfortunately passed away a few years later, and a group of other diving friends and photographers.

We knew that whale sharks (Rhincodon typus) had been spotted in the area on a regular basis for several weeks, and that they often gather in loose aggregations. Of course, you never know how any given day will unfold. Finding the sharks was easy enough, but getting close to them to take a good picture in the greenish water proved to be a bit of a challenge. The water was greenish because it was full of plankton. The presence of plankton was the good news because it is whale shark food. The bad news was the visibility was in the neighborhood of 15 or 20 feet. That's not much when it comes to trying to photograph a big animal that can easily out swim you.

After a couple of hours taking turns trying to slip over the side and swimming as fast as I could to try to intercept an oncoming sharks, my legs were starting to get a little wobbly so I decided to try another strategy. Instead of chasing the sharks, I decided to see if we could look for dense clouds of plankton on the surface. That strategy worked!

We found a pocket of plankton and I slipped over the side. As I did I saw a whale shark swimming right at me mouth agape. Close my eyes and I can see the entire event unfold as plain as day.

I was not using strobes because I knew they would slow me down and because of all of the plankton I knew that backscatter would be a potential problem. It was a beautiful afternoon, meaning lots of sun, but it was beginning to get a little late in the day so one of my first thoughts was to try to get myself onto the sunny side of the whale. That thought came from previous experiences photographing other large animals. If you are on what I will call the shady side of Mr. Big, whoever that may be, you can capture some nice images, but the animal tends to lack strong detail. Eyes and other facial features often become difficult, if not impossible to see in your photographs.

It might have still been bright enough on this day to get a good shot from the shady side, but I managed to get on the sunny side and stay there for a series of shots as this whale shark approached.

As you probably know, whale sharks are the world's largest fish. According to a statement published by National Geographic the largest specimen ever documented was 40 feet long. However, I believe I have seen several whale sharks that were slightly larger than that, and a number of leading specialists believe that whale sharks might attain a length of 60 feet or more. The problem, of course, is getting a whale shark to hold still while you get an accurate measurement!

A large whale shark weighs in the neighborhood of 30,000 pounds. Their enormous size alone makes whale sharks rather easy to identify, but other prominent characteristics include the ridges that run the length of their body, whitish spots on the top portion of the body, and the position of the mouth. Whale sharks have a wide, flattened mouth that is located at the front of the face (the terminal position) as opposed to being underslung as is the case in most species of sharks. The body color of whale sharks varies, but they are generally grayish to brown to dark blue.

Whale sharks are filter feeders, relying on the smallest animals in the ocean, plankton, as their primary food source. When feeding, a whale shark moves huge quantities of plankton-filled water through its mouth and out its gill slits. Structures known as gill rakers, which are located in the shark's mouth just in front of the esophagus serve to collect the plankton. Whale sharks also feed upon some small schooling fishes and squids, and have been known to swallow tuna or jacks in the two to four pound size range.

Feeding whale sharks often swim mouth agape near the surface where plankton concentrations are dense. This makes the sharks easy to spot from a boat or a spotter plane. However, once a diver or snorkeler jumps into the water, the sharks typically keep right on swimming, making them difficult to keep up with. From the air or the deck of a boat, whale sharks might look like slow swimmers, but it is another matter altogether to try to keep up with one in the water!

Whale sharks are equipped with musculature that allows them to essentially stop swimming for brief periods and suck in plankton-filled water. The sucking power is rather strong and I felt it when I got within a few feet of a shark that was actively feeding right in front of me. Sometimes feeding whale sharks orient in a vertical head-up/tail down position and bob up and down a few feet below the surface as they suck in copious amounts of plankton.

With the possible exception of the Mediterranean Sea, whale sharks are found in all the tropical and subtropical oceans throughout the world (including the waters in Captain Steve's backyard off Maui!) and tend to occur close to coastal regions. These behemoths have approximately 15,000 teeth arranged in approximately 300 rows in each jaw, but you can relax, the largest one is only about 3 mm long. The docile sharks use the teeth to hold food until it can be swallowed.

I captured this week's POTW with a Nikon 12-24 zoom with the lens set at 12 mm. One way to translate that information is to figure that I was roughly 5 feet from the shark when I captured this image. There is no doubt that the excitement factor makes my adrenalin flow, but when free diving, too much adrenalin quickly becomes the enemy and a limiting factor as you burn through your oxygen. Knowing that, I made a conscience effort to try to relax and slow things down so I could hold my breath a bit longer and get in front of a feeding whale shark.

In addition to that I used a free diving technique that I had learned years earlier in southern California from Jim Watt, a long-time superb free diver. My habit had always been to slip into the water as quietly as I could, and then take a breath and dive down and swim toward whatever subject I was trying to get close to. Jim taught me to use the momentum of my entry to propel me downward and toward my subject. In other words, in a single motion Jim taught me to slide into the water camera in-hand and instead of immediately surfacing to keep right on trucking toward my intended subject.

Jim's tip might seem like a small thing, but it helped me get this shot as well as a number of other big animal images over the course of my career. Thank you Jim!

For this week's POTW I set my light meter to matrix metering, Nikon's terminology for allowing the meter to read a wide area. I set the camera on shutter priority with the shutter speed at 1/160th of a second. In short, I used a relatively fast shutter speed, but with my ISO selection set to ISO 200 I thought the combination would give me an f/stop of f/8 or higher (meaning more closed down, f/11, f/16 etc.). I was concerned about my aperture because with this lens I know I need to use an f/stop of f/8 or smaller to be sure the edges of my frame are sufficiently sharp.

Of course, I also realized that a little softness on the edges of a photograph of an oncoming whale shark that was feeding with mouth agape would not be ruinous. In fact, I would hope that for a shot of a feeding whale shark in the center of the frame that not many people would pay much attention to the edges of the frame.

All of that said, the summary of how I got this week's POTW is as follows: While on the panga we found a dense pocket of whale shark-attracting plankton, and maneuvered the skiff to within a few yards. With my camera in the shutter priority mode I selected a relatively fast shutter speed to help me "freeze" the action. I used Jim Watt's free diving technique and wiped the entry bubbles off my dome port as I was swimming toward the shark. I made an effort to get onto the sunny side the shark. With my camera set to shoot as many frames as possible per second I composed and shot as many frames as I could as the shark fed. Piece of cake, and a moment I'll remember for as long as I live!