Whaleshark Koh Tao
Learn about the Whaleshark on Koh Tao
A Whaleshark is part of the shark family and often incorrectly thought of as a whale, which makes it the biggest fish in the ocean and one of the most popular to appear on the bucket list of scuba divers.
Where to find a Whaleshark on Koh Tao
Koh Tao is very famous for Whaleshark sightings and although they appear more in certain months, Whalesharks still make surprise appearances all year round.
How to Identify a Whaleshark
The size of a Whaleshark dwarfs nearly every other marine species we see on Koh Tao and they have a flattened head with a blunt snout above their mouth.
A Whaleshark has protruding whisker-like short barbels from their nostrils that act as sensory organs very similar to catfish and their eyes have a covering, which is hard with tooth-like scales that are known as denticles.
Whaleshark is the Largest Fish in the Ocean
The underbelly of a Whaleshark is completely white and the rest of the body is a mixture of grey and blue, which is made up of white spots and stripes and their hide can be as thick as 10 cm.
A Whaleshark is one of only three shark species to filter feed using cross-flow-filtration and they open their mouths which can be over 1 metre wide, close to the surface and sieve water through their gills.
Whalesharks can gulp and process over 6000 litres of water an hour and even though they have over 3000 tiny teeth, they cannot bite or chew.
Whaleshark Characteristics & Behaviour
Unlike most sharks, a Whaleshark propels itself using its entire body to help it move around our oceans rather than only using its caudal fin (Tail Fin).
Whalesharks are gentle giants and are very majestic with their movement and they glide rather than swim fast through the water.
Very little is known about the breeding habits of Whalesharks however, they are ovoviviparous, which means that baby Whalesharks are hatched from eggs that are kept inside the body of the mother and once formed, they are born.
Gentle Giants of the Ocean
Fully grown Whaleshark adults can reach up to twelve (12) metres in length and weigh more than seven (7) tons, so they have few predators.
However, as a juvenile they are vulnerable with some studies estimating less than ten percent (10%) of baby Whalesharks make it to adulthood.
For this reason, they have a considerably fast growth rate in the early stages of their lives and can easily gain over one hundred kilograms (100Kg) in their first few years of life.
Interesting Facts about Whalesharks
Whalesharks have their own unique pattern of spots behind their gills, which is unique to them, similar to human fingerprints.
These unique markings have enabled scientists to track individuals and it has provided us with more information on their migratory patterns and other behaviour.
During the early 2000’s an Astrophysicist from NASA worked alongside a fellow conservationist to help build an algorithm that helped filter through records of photographed Whalesharks to pin point their migration history.
Unique Patterns help Identify Whalesharks
It is believed the system worked very similar to identifying white spots on a black night sky to the white spots on the flank of a Whaleshark.
It is unknown why, but studies have shown many Whalesharks can plunge to depths of between 2000-3000 feet and one particular recording was tagged and spent over 12 hours at 3200 feet deep.
In 2009, a group of scientists in the Philippines discovered a baby Whaleshark that was only thirty-eight centimetres (38cm) long, which is still believed to be the smallest living Whaleshark ever recorded.