Leopard Sharks

Leopard Sharks are the common Name in Asia for Stegostoma fasciatum,which is very common on the Similan and Surin Islands.

 

In The Americas it is the name for a very different shark – Triakis semifasciatum.

We see Leopard Sharks on many of our dive sites. Some common sites are Koh Bon, bon Soong wreck and Koh Tachai. We also see them on many other sites, but not so frequently.

Here is a blog entry from one of our guests:

While on holiday last winter to the Similan Islands, Thailand I had the opportunity to go diving for the first time. I like, many others, had heard of the horror stories of sharks in the oceans and I would be lying if I said I was not nervous when I was told we would be going to see a species of shark called a “Leopard shark”. The name leopard shark immediately put an image of this huge sea monster in my mind but once we got to the dive site I could not have been more surprised and amazed at what fantastic creatures leopard sharks are.

 

When I first saw this amazing creature swimming along the ocean floor I was really amazed. The name leopard shark is very fitting due to the spots on its body. I was a bit apprehensive and expected the shark to earthier come flying at me or simply swim away. Despite all the comments that these are actually friendly creatures in the dive briefings, I was still not sure. Our Instructor, Gae, told us that if we did see one we would slowly approach from the front and spend some time with one. I have since learned that leopard sharks are not usually bothered by humans and spend much of their time laying on the sand.

As I did my dive during the day time the leopard sharks that we saw were very inactive, just laying on the bottom which makes sense, considering that they are nocturnal sharks. In many areas leopard sharks are used to divers and if you do not get too close then you can observe them really well. We were that lucky! Wicked Diving is very specific about not getting too close to any marine life…but I never believed that I would be hovering 2 meters from a shark….but I was! Most of the time leopard sharks will laze around in a sheltered area. In this case, one shark was lying right next to a large coral head off Koh Tachai. We also saw two at Koh Bon the next day.

Since diving the Similan Islands made such a great positive impact on me I became really interested in leopard sharks my local sea life center has a few there and I have been to observe them there. I have found out a great deal more information about these creatures since my dive. One of the most fascinating things is there diet as I am sure when most people hear the word shark they imagine a great white eating anything it can find in the ocean. The leopard shark has a diet that consists of things like snail’s sea snakes and small fish. It hunts at night getting into all kinds of nooks and crevices to hunt for its prey.

Something that is quite unique to leopard sharks and that is unlike many other species of shark is that it does not need to swim in order to be able to breath. I noticed this on my dive that the leopard shark was not moving and was just lying there. I asked Gae when we returned to the surface what the reason for this was and it turns out that the leopard shark can pump water over its gills. I found this really interesting and have since learned that more often than not leopard sharks will lie on the bottom of the ocean facing the current as this helps them breathe even easier.

I just want to say again what amazing creatures these are and I can not recommend taking the chance to see them in the wild. The leopard shark was a huge influence on me in getting more interested in diving and now I’m doing my rescue course and hoping to head back to Wicked Diving, Khao Lak for a Divemaster Course.

Thanks for that! We look forward to having you join the divemaster team here at Wicked!

More details in the Leopard shark

Description & Behavior
The zebra shark, Stegostoma fasicatum (Hermann, 1783), is also known as a leopard shark in SE Asia. The zebra shark has a cylindrical body with prominent ridges on the sides and 5 gill slits (slits 4 and 5 overlap). The tail lacks a ventral lobe and it is as long as the body. This shark has a broad head, small barbels, and a transverse mouth located in front of the eyes. Its spiracles are as large as its eyes. The spineless dorsal fins are back to back. The anterior dorsal fin is much larger than the posterior dorsal fin. The first dorsal fin appears above the bases of pelvic fins, the second dorsal fin is about as large as the anal fin. The body is gray-brown with dark spots in adults. Juveniles are darker with light stripes and spots. Maximum size is about 3.5 m, average size between 2.5-3 m.

World Range & Habitat
Indo-Western Pacific: South Africa to Red Sea and Pakistan, India, Sri Lanka, Bangladesh, Indonesia, Thailand, Vietnam, Philippines, China, Japan, Australia, New Caledonia, Palau. Lives over the continental and insular shelves. Very common around coral reefs, often on sandy bottoms, but little is known about its biology. It is known that this species props up its pectorals in the sand and faces the current with open mouth. Such behavior and its inactivity during the day points towards a more sluggish life style and indicates that it is probably a nocturnal hunter. Recorded to have entered freshwater.

Description & Behavior
The zebra shark, Stegostoma fasicatum (Hermann, 1783), is also known as a leopard shark in SE Asia. The zebra shark has a cylindrical body with prominent ridges on the sides and 5 gill slits (slits 4 and 5 overlap). The tail lacks a ventral lobe and it is as long as the body. This shark has a broad head, small barbels, and a transverse mouth located in front of the eyes. Its spiracles are as large as its eyes. The spineless dorsal fins are back to back. The anterior dorsal fin is much larger than the posterior dorsal fin. The first dorsal fin appears above the bases of pelvic fins, the second dorsal fin is about as large as the anal fin. The body is gray-brown with dark spots in adults. Juveniles are darker with light stripes and spots. Maximum size is about 3.5 m, average size between 2.5-3 m.

World Range & Habitat
Indo-Western Pacific: South Africa to Red Sea and Pakistan, India, Sri Lanka, Bangladesh, Indonesia, Thailand, Vietnam, Philippines, China, Japan, Australia, New Caledonia, Palau. Lives over the continental and insular shelves. Very common around coral reefs, often on sandy bottoms, but little is known about its biology. It is known that this species props up its pectorals in the sand and faces the current with open mouth. Such behavior and its inactivity during the day points towards a more sluggish life style and indicates that it is probably a nocturnal hunter. Recorded to have entered freshwater.

Endangered Species….

Read the UN report on endangered species…