A Front Row Seat at a “Car Wash” for Sharks

Photo courtesy from Scuba Diving Resource

In one way or another, we all love scratching our back. It soothes or makes us satisfied when we take care of that itchy part. And guess what? So do sharks, but how?

Unlike humans having long arms that can extend and reach the back part of the shoulder, sharks need a medium to scratch their back, or should we say take off their dead skin cells, bacteria and parasites present in their skin.

Photo courtesy from Underwatercam

The only way to do this is they go and visit a cleaning station where cleaner fish awaits them. Pretty much the same way a car wash operates, the only difference is that the cleaner fish does this in a symbiotic relationship where they get a free meal out of dead skin and parasites while sharks are being cleaned.

In Costa Rica, hundreds if not thousands of sharks swarm the waters of Coco’s island and one of their purpose in dropping by to this offshore island is to get cleaned. Now, get ready as we give you a front row seat and take you to a tour on how sharks are being cleaned in Coco’s Island.

The Cleaning Station aka Car Wash Center for Sharks

A cleaning station is often located near the ledges of a reef system where the shallow water of a coral reef ecosystem meets the deep open water environment.

Photo courtesy from Flickriver.com

When a shark approaches a cleaning station, they send a gesture or signal that it needs to be cleaned. This signals include the opening of the mouth in the case for a jaw or dental cleaning or sets its body in a motionless position. Once the shark achieves this neutral-motionless state, cleaner fish can do its job or should we say feast on dead skin and parasites.

On the funny side, one of the workers in the said car wash center are the Bluestreak Cleaner Wrasse (Labroides dimidiatus). Usually a typical car wash center is being managed by a pair of adult bluestreak cleaner wrasse and assisted by a group of juveniles. For sharks (if only they can read this article), the cleaning intensity of a bluestreak cleaner wrasse is continuous and random and is not based on the size and species of its client. In short, there are no reservations: whoever comes first, gets cleaned first.

For larger species of sharks, other reef-associated fish come in to help or should we say share with the feast. The scheduled early morning cleaning of Hammerhead sharks, Galapagos and Blacktip Sharks are taken cared by butterflyfish (Chaetodon spp.) and Angelfish (Pomacanthus spp.). You will be amazed in this coordinated fashion where you can see these sharks line up while approaching the reef filled with awaiting fish.

If you can take a closer look while sharks are being cleaned, you can see that it’s not just their outer body that’s being cleaned. Aside from the opening of its mouth for a dental clean-up, sharks also open and widens their gills allowing the cleaner fish more access to clean the internal part of its jaws.

Now, here’s the bad trip part: It’s not all the time that sharks are satisfied with the cleaning process. As they said: there’s always a black sheep in the family and so does with a cleaning station. Having the same shape, size and color pattern of a cleaner wrasse, a certain species of blenny mimics the work of other cleaner fish. Also called as the False Cleanerfish (Aspidontus taeniatus), this fish will initially help in the cleaning process, but when the opportunity arrives, bites and tears off some flesh sending off the shark in pain.

Dive Sites in Coco’s Island with a Cleaning Station

A shark sighting in Coco’s island can be considered a guarantee in all of its 20 plus dive sites. But not all of these sites have a cleaning station. Here are some of the dive sites in Coco’s Island with an established car wash center for sharks.

Bajo Alcyone

Considered as the best dive spot not just in Coco’s Island but in Costa Rica as well, Bajo Alcyone is home to a large population of hammerhead sharks. You will start your dive by descending down to 25 meters (82 feet) arriving at a huge crevice.

Photo courtesy from Matthew Meir-PhotoShelter

Also called as the Halcion Cling, you will hold on the rocky protrusions as mild to moderate current is always present in the area. Once settled, you will observe that hammerhead sharks will gently glide from distant scene and may come close to you. Some divers who are lucky enough were able to take a selfy picture while hammerheads are on the cleaning process. Caution: this site is recommended only for certified Advanced Open Water Divers.

Dirty Rock

This is another equally amazing site for shark interaction where novice divers can enjoy. The dive starts by plunging down to a channel between boulders and pinnacles which forms a sheltered refuge. You will then traverse down to the ledge where your shark interaction begins.

Silverado

Photo courtesy from SharkSchool

If you want to see and interact with other species of shark, then explore the site called Silverado. Named after its featured shark species, diving in this site allows you to see a good population of silvertip sharks. At their cleaning station, these sharks may tolerate our presence allowing us to come close to them to as near as a few meters.

Its not just sharks that are getting cleaned in Coco’s Island. Other species like manta rays and groupers also take this opportunity to let their backs be scratched. But of course, all these species are not simultaneously cleaned where each species has its own time in the cleaning station, just like a reservation at a car wash. Who wants their BMW sports car being cleaned side by side with a lorry?

At the end of the day, the functionality of a cleaning station and the mystery of the ocean has been the subject of many stories. And mind you, this mix of underwater energy has led to the production of a computer animated comedy film that has been patronized by both children and adults around the world which had made them more aware and concerned on the conservation of our oceans.

Reference:

Fishbase: www.fishbase.org

Sea Turtles: www.seaturtles.org

Wikipedia: www.wikipedia.org

Video courtesy from ChanLiang

About Tristan Paylado
Tristan is a marine biologist and a CMAS 2-Star Dive Instructor
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