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Pictures please – spot the leopard!

DSS’s Georgina admires a leopard shark

The leopard shark (Stegostoma fasciatum, also called zebra shark) is a very distinctive shark within the shark-family and have a unique appearance: 5 ridges down their back and a single-lobed tail which is almost as long as their body. It seems to be the closest relative of the whale shark with its ridged body shape and spot patterns. These nocturnal hunters are also the largest egg-laying sharks. During the day divers and snorkelers are able to see them just resting on sandy bottoms near coral or rocks.

Little is known about the leopard shark. Christine Dudgeon started studying leopard sharks in Australia for her doctoral thesis 10 years ago. Until then hardly any studies had been conducted on leopard sharks in the wild. Like most shark and ray species, leopard sharks can’t cope with fishing pressure because of their slow reproduction rate and late maturity.

To obtain data about the leopard sharks, Christine started the project “Spot the Leopard Shark”. The project team collects pictures for identification: like manta rays, whale sharks and other species, each individual leopard shark has a unique spot pattern, but do however undergo one of the most dramatic changes in body markings of any shark. They are born with stripes that transform into spots while they mature. It is unknown when the patterns stop changing. But during Christine’s Australian study, it was determined the spots are stable in the adults.

With so many divers in the water armed with cameras, the capacity for collecting data is fantastic. And with high speed internet photos can easily be submitted and stored in a central database.

Juvenile leopard shark and egg cases in Georgia Aquarium

In southern Queensland the leopard sharks aggregate in large numbers over the summer months every year. So over the last 10 years of studying them the project showed some pretty amazing stuff. Briefly, an estimated 460 mature adult sharks are part of the annual aggregation; they can swim quite long distances (the record for 1 shark is ~400km in 1 month); they don’t like water below 22 degrees C or rough water conditions and most importantly for the Spot the Leopard Shark project, the spotting patterns in the adults are stable with individuals matched up to 12 years in the wild!

Spot the Leopard Shark – Thailand

In Australia leopard sharks are not fished and their populations are healthy, but outside of Australia it is a different story and it’s really time to start using the techniques developed for the Australian project to help understand and protect this species where it’s needed.
That is why the project was expanded to Thailand, where it is a joint venture between Thai researchers (Phuket Marine Biological Center), Australian researchers (The University of Queensland) and the diving community of Thailand.

Dr. Kongkiat, Phuket Marine Biological Center en dr. Christine Dudgeon, University of Queensland

It was set up as a community project on August 2013 on Phi Phi Island, where the leopard shark plays a big role in the eco-tourism / diving-tourism. Every diver can get involved by submitting any photos of leopard sharks taken in Thai waters that will be used to determine how many leopard sharks there are in Thailand, habitat and habitat changes, life span etc.

Get involved, spread the word and contribute your photographs! The website will show a gallery of all identified sharks and you can check if your photos match others. You can name newly discovered sharks! Older pictures can be submitted as well, as long as you are able to provide basic information about the picture, like location and date and any other info.

More information:
https://www.facebook.com/SpotTheLeopardShark
https://sites.google.com/site/spottheleopardshark/thailand

More infomation about Christine Dudgeon:
www.uq.edu.au/whale/christine-dudgeon

This text was supplied by Daniel (Snippy) van Dongen, a Dutch diving instructor, who has spent many years in Thailand and who is now located on the beautiful Phi Phi Island.
He has contributed and participated in several shark related projects from releasing/tagging bamboo shark, raising shark awareness, Blacktip reefshark monitoring and, of course, assisting in the Spot the Leopard shark Project.
More information about Daniel: facebook.com/SnippysSnapsDiving

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