The Gentle Giants of Baa Atoll By Kate Wilson MSc.
The whale shark:
Rhincodon typus
The whale shark is a massive filter feeding shark...
It spends a lot of its time feeding on microscopic plankton at the surface of the ocean...
It is the largest living fish in the world, growing up to a massive 20m in length...
Age estimates for whale sharks are as high as 60 years, but no one really knows how long this species lives, some estimate they may live for more than a century...
Elasmobranches
Elasmobranchs
Carpet sharks
Whale shark colouration
The checkerboard pattern could be a result of its evolutionary relationship with carpet sharks that have bold patterns for camouflage, such as this Leopard shark.
These pigment patterns could also be an adaptation to protect against the suns harmful ultraviolet rays...
Distribution
Diet
Unlike most plankton feeding vertebrates, the whale shark does not depend on movement to operate its filtration mechanism...
Rather they actively opens their mouth, distend their jaws and actively suck in water...
This sucking mechanism enables the whale shark to capture larger and more active prey as well as zooplankton aggregations.
The whaleshark then closes its closes its mouth and the water flows out the gills.
Whale sharks are also seen diving down and moving up in the water column
It appears that these movements are also associated with feeding.
The whale shark ‘cough’
Danger to humans
Predators
15 inches
Finally in 1995, the answer was found... •
.
Male Female
RESIDENT POPULATIONS • •
Baa Atoll Utila
Feeding grounds
Time and time again, researchers see whale sharks with amputations and lacerations associated with small boat strikes.
Boat strikes and flocks of tourists are not the only threat to whale sharks.
Jordan
Harpoon
Whale shark hunting for meat however, is not the main problem...
Findings so far...
Joey
So how do we know whale sharks undertake these large scale migrations?
The Maldives Whale Shark Research Program
How...
Identification
So how many are in Maldives?
Growth rates
How you can help? • Any whale shark photos of the area behind the gills, please note the time, date and area you saw the shark. We can then send the photos off to the research team. • Ask your tour operator for a briefing on the encounter guidelines • Don’t buy shark products, instead buy local handicrafts • Get actively involved in one of the Maldives Whale Shark Research Project’s expeditions
http://www.maldiveswhalesharkresearch.org
www.sharkwater.com