Trip report: Wetpixel Whale Sharks 2017

The 2017 Wetpixel Whale Sharks trip kicked off today in Isla Mujeres, Mexico. Strictly speaking, it started yesterday, with the team arriving at the Playa la Media Luna hotel throughout the day. Today was our first trip out on the water though, so it counts as Day 1!

There are six participants, and after a quick briefing over breakfast we made our way out to the golf carts that are used throughout the island to get around. Sadly, one of the carts decided that starting today was going to be an issue. When in Mexico, it is important to think “on the hoof,” so we used the remaining working cart to ferry everyone down to the jetty.

Despite this, we were still away by just after 8 am. While we were cruising towards the North to find the sharks, our skipper, David was explaining the new permit system that is now in place for operators that wish to take groups out to see the sharks.

David and Pascquale of Keen M

Each captain and crew member must mow attend a course on correct interactions with the sharks, and there is now a maximum of 2 people plus a guide allowed in the water at a time. On our trips, we have 6 people maximum on the boat, so this allows for plenty of interaction with the sharks.

David also mentioned that in order to get the permits, staff from Keen M literally camped out at the government buildings. The number of permits that are issued have been significantly reduced, which increases the pressure to get the ones remaining. The goal is to limit the number of boast visiting the aggregation to reduce the environmental impact. On a very subjective measure, the number of boats out on the water today did seem less and they seemed to spend less time with sharks. The bulk of them had arrived by 10 am, but by 1.30 pm, they had all gone.

After an hour or so, we found big group of shark and the first group of three entered the water. There were large number of sharks all around the boat feeding on the numerous bonito (Sarda sarda) eggs that are in the water. The sharks gather off Isla Mujeres to feed on these small eggs, the largest fish in the oceans gathering in vast numbers to feast on them.

Pretty soon we found a shark that was performing a “botella” or bottle. When the whale sharks find a patch of particularly dense food, they stop swimming. Their normal feeding technique is known as ram feeding. Essentially, they swim while opening and closing their mouths using their momentum and the suction of the mount movement to force water through their mouths and out through their gills. When they stop, their tails sink and they then adopt a vertical position in the water. By opening and closing their mouths they literally gulp the plankton rich water and push it through their gills.

This vertical feeding behaviour has only relatively been scientifically described.

While they are in a botella, it is possible to approach the sharks quite closely, as long as this is done carefully, calmly and slowly.

Everyone in the group was able to capture great images and spend plenty of time in the water. We had over 100 sharks in a really dense grouping. Looking forward to lots more tomorrow.

Day 1.
Day 2.
Day 3.
Day 4. Day 5.
Day 6.
Day 7.
Days 8/9/10.