Thursday, 3 September 2015

Shark Week: Day 4

Day 3 of Shark Week saw one of our environmental officers Dave McCann taking the stage for the evening presentation. His talk was entitled 'Marvellous Rays' and covered a number of fascinating topics, focusing specifically on the species of rays we encounter in the waters of Sabah. For those of you who are familiar with the blogs and Scuba Junkie Facebook, or for those who have been lucky enough to dive in these waters, you will already be well aware of the wide range of rays we are fortunate enough to witness on a regular basis.

In the Sabah waters, divers and snorkellers have regular meetings with blue spotted ribbon tail rays and blue spotted sting rays, but the focus of Dave's presentation was the larger of our ray species. We have been lucky to see Manta Ray, Mobula Rays (commonly known as Devil Rays) and Eagle Rays in and around the Tun Sakaran Marine Park, Pulau Sipadan and Mabul as well as along Sipadan Barrier Reef.

Dave discussed how to differentiate between the two currently described species of Manta: the Giant Manta (Manta Birostris) and the Reef Manta (Manta Alfredi).  It speaks volumes to how little we know about the underwater environment when Dave informed the audience that it was only discovered that there were in fact 2 different species of Manta in 2008. This was one of the largest new species to be described by scientists in many years, and in fact Dr Marshall, who made this initial distinction, may have recently discovered a third species of Manta that she is currently trying to describe. That we know so little about these amazing creatures should inspire us as frequent explorers of the aquatic world to get involved in the conservation of these amazing creatures.

Dave then went on to discuss the spectacular Devil Ray. He stressed that whilst divers are often disappointed to learn that it was not a Manta they saw but a Devil ray, these stunning rays are more than a match for their larger cousins. Ways to distinguish the Devil Ray from the Manta include the position of the mouth - with Devil Rays the mouth is situated on the ventral (underside) of the animal, whereas on the Manta it takes a more anterior (frontal) position. The Manta also possesses a unique pattern of spots on it's ventral surface which can be used much like a fingerprint in order to i

dentify the creature. 

We have been lucky here at Scuba Junkie to witness schools of up to a hundred Devil Rays along the Sipadan Barrier Reef, surely a highlight in any divers career! Both Devil and Manta Rays can school in huge numbers

Dave wrapped up his talk by informing the audience of both the threats that Rays face all around the world, as well as what we as responsible divers and tourists can do to assist these gentle giants. There is a growing market for the gill rakers of the rays as many believe that it has medicinal qualities. By raising awareness of these issues we hope that we can make a change!

Facts about White Tip Reef Sharks:

  • These grey-brown sharks have white tips on their dorsal and tail fins
  • It is a very small slender shark 
  • Typically they are a docile shark, but at night they can become aggressive in their hunting
  • After a gestation period of roughly a year, the female will give birth to 1 to 5 pups. 
  • They reach sexual maturity at just 5 years old 
  • They are listed as 'Near Threatened' on the IUCN Red List

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