Whale Shark Presentation (2012)

Whale Sharks!
What are Whale Sharks?
Cartilaginous Elasmobranch Fish
• 1050 Species
- 500 Species of Sharks
- 550 Species of Rays
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400 Million Years Old
Skeleton Made of Cartilage
Internal Reproduction
5-7 Gill Slits
160 million
year old
Blanket Ray
370 million year old
shark called
Cladoselache
Great
White
Shark
Whale Shark Relatives
Basking Shark
Megamouth Shark
Cold water filter
feeder
Deep water filter feeder
Convergent evolution!
Whale Shark Facts
Global Distribution
Captain Charles Thompson off Miami
harpooned this 38-foot-long whale shark that
reportedly took about 39 hours, five harpoons
and more than 100 bullets to subdue
Largest Recorded Whale Shark:
Width = 12.6m & Weight = 15 tonnes
Smallest recorded Whale
Shark : 15 inches!
This rare Albino Whale
Shark was seen in the
Galapagos
Whale Shark Feeding
Vertical
vacuum
feeding
Huge mouths and gills filter out the tiny
planktonic animals from the water
Planktonic Mysid
Shrimp
Feeding on Snapper eggs in Belize
Whale Shark Predators
Whale Sharks have very
few natural predators.
Their main predators
are…..HUMANS!
Orca or Killer Whale
The remains of juvenile Whale Sharks
have been found in the stomachs of
Blue Sharks & Marlin
Whale Sharks in Captivity
Keeping Whale Sharks in captivity is a
controversial issue when trying to balance
education, tourism and conservation
The longest a Whale Shark
has been successfully kept
in captivity is a 12 yr old
male in Okinawa Aquarium,
Japan (above)
Whale sharks can be
found in aquariums in
Japan & USA.
Hitchhikers
Giant remoras seek
shelter around the
pelvic fins of this
ocean wandering giant
In the south of the Maldives shark
sucker remoras coat the bodies of
the night feeding whale sharks
Whale Shark Breeding
Whale sharks have internal
fertilization and produce live young
Important Questions:
• Where & when do they breed?
• Age of sexual maturity?
• Gestation period?
• How often do they reproduce?
Males can be distinguished by the
presence of two claspers near the
pelvic fin
Very little is known of the
reproduction of Whale Sharks
Threats to Whale Sharks
Boat Collisions
By-Catch
Whale Shark Fisheries
India
Drying
fins
Partially finned shark
in the Maldives, 2008
Whale Shark fins can sell
for more than $10,000 on
the black market
Oil from the livers of the sharks
was traditionally used to seal
wooden boat hulls
Taiwan
Global Protection & Tourism
Whale Sharks are listed as “Threatened” by the
World Conservation Union (IUCN)
Whale Sharks
are listed on
Appendix II of
CITES
In 1995 all fishing, selling, importing
and exporting of whale sharks for
commercial purposes was banned in
the Maldives and has been banned in
the Philippines since 1998, India in May
2001, followed by Taiwan in May 2007
Through tourism, Whale Sharks
generate hundreds of millions
of US dollars in direct revenue
each year
Maldivian Whale Shark Project
www.maldiveswhalesharkresearch.org
Photo
Identification
Discoveries to Date:
•95% of the sharks are immature males
•Using Photo-Identification, over 1,000 sightings of just
200 identified sharks have been recorded
•The individuals seen in Baa Atoll are the same sharks
which are seen in South Ari Atoll
•Huge percentage of the population with anthropogenic
related injuries (harpoons, nets, boat strikes, finings)
Scientific information gathered by
these projects is being used by the
Government to implement
protective measures to safeguard
these animals within the Maldives
Tourism Guidelines
• DO NOT attempt to touch, ride or chase
the whale sharks
• DO NOT swim directly in front of the
whale sharks
• DO NOT restrict the normal movements
or behaviour of the animals
Guests get face-to-face with a giant
whale shark at Hanifaru
Thank You!