The Elusive Whale Shark

It is the largest fish in the world, measuring up to an impressive 50 feet in length and weighing up to 15 tons. It has a mouth that can stretch to four feet and a jaw lined with over 3,000 teeth. Yet, despite its intimidating presence, this creature is completely harmless to humans. In fact, the whale shark can't be bothered with attacking humans; tiny fish are its prey of choice. Unfortunately, though, in some countries, with the exception of Belize, the whale shark has increasingly become prey to humans. Consequently, the World Conservation Union has recently listed it as an Endangered Species.

Although this fish is not part of the whale family, it has a size that rivals many whale species. The average size of a whale shark is 25 feet, though there have been sightings of 50 foot individuals. Only last week there was a report of a 35 foot whale shark observed in coastal waters north of San Pedro. In addition to its large size, the whale shark is also characterized by a flat, broad head and a rounded snout. It has five large gill slits, two dorsal fins and two pectoral fins and distinguishable coloration that includes light yellow stripes and dots on dark gray skin.

The whale shark prefers tropical and warm temperate waters all over the world, spending most of its time in coastal areas, and swimming near the surface of the water. Whale sharks are predominantly solitary creatures, although pairs are seen occasionally. When it's time to feed though, the whale shark almost always chooses to work alone. In spite of a mouth full of sharp teeth, the whale shark feeds on an enormous amount of tiny plankton using a technique known as filter feeding. The gills of the whale shark are covered in webbing allowing water to pass through the mouth and over the gills, straining out plankton and sending the remaining water out to the sea. Whale sharks do not have to travel quickly through the water to filter feed; most often, in fact, they travel less than three miles per hour.

Reef Brief is a weekly column published in the San Pedro Sun

To the contrary, Belize is making every effort to protect and learn more about this elusive creature. TIDE, an environmental organization located in the Toledo district, has begun a tagging program, in which individuals are equipped with a satellite radar tag to track migration. It is already known that whale sharks cluster in areas where grouper spawning takes place, usually occurring around the full moon. March and April are the peak months for whale shark sightings, typically occurring near Placencia. This year, however, Green Reef has already received several reported sightings around Ambergris Caye.

It is our hope that other countries will follow the lead of Belize and begin to realize the significance of the whale shark and the importance of protecting them.

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