Here are some photos from our whale shark trip. They are not very clear, but actually look much better than the printed originals. I used Picasa from Google Labs to clean them up. Click on them to see a larger version. Be sure to check out the original post that was posted August 16.
The first picture is his mouth. If you look under his mouth you can see a set of snorkeling fins. This can give you an idea of the size of the creature. Then there is a fin to the top right of the photo which gives you perspective again.
The water was very murky. I have been scuba diving where you could see well over 100 feet. Once I was in 120 feet of water and you could easily see the details of the bottom of the boat. The day these photos were taken the visibility was 20 feet or less. When you got far enough away from the fish to take a picture or even really see it from end to end the visibility would make it hard to even see that there was any animal there at all.
When I first jumped in the water I stuck my head in and looked for the shark. All I saw was mouth. A little disconcerting to say the least. The boat dumps you in at the front of the shark so that you can swim along with it. If you are not a strong swimmer, then you would miss the opportunity to see it. So getting out at the front, and therefore the mouth, you get a chance to see the whole fish.