1. PART 2: BIOLOGY & ECOLOGY © Scubasigns

2. PART 2: BIOLOGY & ECOLOGY Outline 1. Taxonomy and Classification What type of animal is a it? 2. Distribution and Habitat Where do they live? 3. Anatomy and Physiology How do their bodies work?

3. PART 2: BIOLOGY & ECOLOGY Outline 4. Feeding and Diet What and how do they eat? 5. Reproduction and Life cycle How do they reproduce? 6. Predators Which animals prey on whale sharks?

4. It has a skeleton made from cartilage Lighter and more flexible than bone It’s skin is covered in dermal denticles Tough, parasite repellent and hydro- dynamic It has several rows of replaceable teeth Teeth always sharp The whale shark is a true shark: 2.1 TAXONOMY & CLASSIFICATION True Sharks

5. These features have made sharks successful animals Appeared 220 million years before the dinosaurs 440 different species of shark Can exist in many different habitats- even fresh water! 2.1 TAXONOMY & CLASSIFICATION Shark Success Bull sharks and river sharks happy in fresh water rivers Smallest is lantern shark just 17 cm long A primitive six-gilled frilled shark

6. CarcharhiniformesCarcharhiniformes Ground Sharks HeterodontiformesHeterodontiformes Bullhead Sharks HexanchiformesHexanchiformes Six gilled Sharks LamniformesLamniformes Mackerel Sharks OrectolobiformesOrectolobiformes Carpet Sharks PristiophoriformesPristiophoriformes Saw Sharks SqualiformesSqualiformes Dog fish SquatiniformesSquatiniformes Angel Sharks 2.1 TAXONOMY & CLASSIFICATION: Shark Orders

7. Zebra Shark Nurse SharkWobbegong 2.1 TAXONOMY & CLASSIFICATION carpet shark features Nostril barbells Prominent ridges 2 dorsal fins Mouth at the front of the head

8. 2.2. DISTRIBUTION & HABITAT Whale sharks are found in tropical and warm-temperate seas Whale sharks live off-shore and close to land They can dive very deep (>1600m), tolerating temperatures as low as 3˚C © Morgan Riley

9. 2.3 ANATOMY & PHISIOLOGY 12.85m largest measured WS.(Prob up to 18m) Whale shark skin is 2mm thick covered with denticles Thick (10-15cm) fatty layer under the skin Spot pattern is believed to be unique to each shark and is used to identify individuals

10. The whale sharks mouth can be 1.5 m wide! The whale shark has 300 rows of very tiny rasp-like teeth that have no obvious function Rhincodon means ‘rasp tooth’ 2.3. ANATOMY & PHISIOLOGY: Mouth © Scubasigns

11. 2.3. ANATOMY & PHISIOLOGY: Eyes The eyes are situated on the side of the head to maximize line-of-sight Vision is probably quite poor - used for detecting movement within 3m Eyes roll when people get too close or exposed to camera flash © Scubasigns

12. 2.3. ANATOMY & PHISIOLOGY: Spiracles Small holes behind eyes Function in whale sharks unknown As with other carpet sharks they may help ventilate gills when the shark is stationary © Scubasigns

13. Two circular nostrils widely spaced, at the front. Nostril ‘Barbells’ similar to Nurse Shark but smaller. Sensitive to dissolved chemicals which can help them locate prey. 2.3. ANATOMY & PHISIOLOGY: Nostrils © Scubasigns

14. 2.3. ANATOMY & PHISIOLOGY: Gills The gills of whale sharks function to extract oxygen and to filter prey from seawater.

15. 2.3. ANATOMY & PHISIOLOGY: Other Whale Shark senses Hearing: Largest inner-ear in the animal kingdom. Probably good for low frequency sounds Lateral Line and Electro-receptors: Unstudied but may have structures other sharks use to detect vibrations and electronic currents

16. 2.4. DIET & FEEDING Prey Whale sharks feed on tiny prey (>0.5mm) including plankton, eggs and small shoaling baitfish

17. 2.4 DIET & FEEDING Ram Filter Feeding Whale sharks are constantly diving and ascending - possibly in search of food They utilise ‘ram filter feeding’… © Scubasigns

18. 2.4 DIET & FEEDING Suction Filter Feeding …or ‘Suction’ filter feeding Suction filter feeding enables WS to feed on more mobile preySuction filter feeding enables WS to feed on more mobile prey Because WS seek high densities of prey they are often seasonal visitors to specific locations Because WS seek high densities of prey they are often seasonal visitors to specific locations © Scubasigns

19. 2.4 DIET & FEEDING Other filter feeders There are two other filter feeding sharks: The Basking shark…

20. 2.4 DIET & FEEDING Other filter feeders … and the Megamouth shark

21. 2.5 REPRODUCTION & LIFECYCLE Male sharks use claspers to deposit sperm inside the female Females store the sperm and may use it to fertilize many eggs Whale sharks give birth to live young – they are Ovoviviparous Claspers © Scubasigns © MWSRP

22. 2.5 REPRODUCTION & LIFECYCLE Pups are about 60cm long when they are born Sexually mature at approx 9m or 30yrs Possibly live until 70 -100 years old Majority of whale sharks encountered around the world are juvenile males © WWF Philippines

23. 2.6 PREDATORS Do not have many natural enemies due to their size Great white shark and killer whale occasionally attack adult whale sharks Young sharks found in stomachs of smaller sharks and swordfish © Dennis Kaandorp