Saving Sharks in Arabia: conference to look at regulating commercial shark fishing

A step in the right direction for shark conservation might be on the horizon in Dubai. A conference will be held this coming week to discuss regulations regarding commercial fishing for several species of hammerhead sharks.  Organized by the UAE Ministry of Environment and Water and Sharkquest of Arabia, the four-day Shark Conservation in Arabia will include government officials and scientists.  

The goal is to determine whether shark fishing, particularly involving the great, smooth and scalloped hammerhead sharks, should be regulated or even banned altogether if the scientific evidence provided by the participants dictates it.  There lies part of the challenge as scientific evidence regarding the populations of these sharks in Arabian waters is a bit on the slim side.

With examples like the reduction in hammerhead populations in and around Mexico and in the Mediterranean, where the loss of hammerheads is estimated at as much as 99.99%, it would seem logic would dictate that Arabia's hammerhead sharks are likely not different from other populations in terms of their slow reproductive rates.  And so, even if the population was robust, at current demand levels for shark fins the Arabian population would evaporate rather quickly if commercial shark fishing went unabated.

It is the hope of local shark conservationists that strong regulations will be proposed and agreed to at the conference.  Such regulations would then be formally proposed at the March meeting of CITES (Convention on International Trade in Endangered Species).  This is necessary as the current trade in sharks in the region, both importing and exporting, involves several different countries.  So the end result must be international regulations or bans, and that is the primary role of CITES.

However, strong opposition can be expected as there is a considerable economic incentive at risk here.  Worldwide, the market for shark fins has been estimated at $1.2 billion USD.  And as pressure continues to mount against it - and as the populations of shark species continue to decline - that dollar figure will go up per pound. 

Hammerheads are not the only shark species at risk.  Sonja Fordham, president of Washington, DC-based Shark Advocates International, recently posted a picture on Facebook of thresher sharks lining a dock in Dubai.  While thresher shark meat can be found on the menus of some higher end seafood restaurants, these sharks are most likely bound for the shark fin market as shark meat can spoil quickly when not properly treated and refrigerated.

The UAE is the fifth largest exporter of shark fins and, judging by these few pictures, it's not hard to see how.  That makes this week's Shark Conservation in Arabia conference all the more important.

Source: The National                    

Hammerhead Sharks: what was Mother Nature thinking?

Discovery Channel's Shark Week starts up this Sunday.  Know how I know?  Easy, just look at all the various shark news items papering the Internet today.  From the latest human/shark encounters to updates on various shark fin ban movements or legislation, sharks are stepping in to fill the void of the close of the summer Olympics.

The Mother Nature Network posted a quick look at the always curious hammerhead shark.  For most folks, great white sharks or tiger sharks can evoke fascination mixed with a little apprehension, but the hammerhead is often the one that leaves them scratching the head in bewilderment.

What was Mother Nature thinking when she drew up the plans on that one?

For me, there are two questions that come to mind with the nine species of hammerhead sharks.  The first is why?  The Mother Nature Network examines the three most common explanations and they all revolve around the shark's hunting capabilities, particularly for the larger species which like to include stingrays as one of their favorite prey.

The broad head of the hammerhead shark increases the surface area where the shark's electrical sensory organs are located.  These gel-filled pores, called Ampullae de Lorenzini, allow the shark to sense the subtle electrical fields given off by animals - as an example, stingrays camouflaged and buried under a thin layer of sand.

With eyes in each end of its head, the hammerhead is also able to increase both its stereoscopic vision (the ability to see directly forward) and its overall field of view (by swinging its head side-to-side, it is able to see above, below, and behind better than many other shark species).  The better the vision, the better the animal is able to hunt.

Finally, when hunting for stingrays, the hammerhead shark actually uses its unique shape to help shovel under a buried stingray, flip it over, and even pin it to the bottom.  This elaborate ballet that allows the shark a measure of surprise while it bites the stingray's pectoral fins, thereby eliminating the prey's ability to escape, has been documented and is quite something to see.

So, those are the three most common explanations as to why - why a hammerhead shark has evolved to have such a unique shape.  There's a purpose behind it that proves beneficial to the shark's survival.

The second question is a much challenging one to answer: How?  We can see why it has this shape and that it benefits its hunting abilities, but how did the evolutionary process start with a "conventional" shaped shark - if, indeed, that was it's original root form - and then Nature said, "Hey, I've got a whacky idea."

Evolutionary researchers have seen evidence of the adaptive radiation process, wherein plants and animals adapt to their surroundings and various requirements to ensure survival, and it takes hundreds of thousands of years for most species.  But there have been occasional jumps or sudden detours - either radical departures from the norm or greatly accelerated changes.  What was the case in the hammerhead shark?  What was happening in its surroundings that the gene pool decided to change little by little from one generation to the next, repeatedly, to where it eventually reached the iconic and unusual shape that we see today.

Evolution is no simple linear, A to B to C, process.  But its underlying motivator, that of survival (of the fittest, the most resourceful, or the smartest) has produced a staggering diversity both on land and at sea.  No better example than that of the genus Sphyma: the hammerhead shark.

Source: Mother Nature Network