A protégée of Dr. Worm, Christine Ward-Paige, actually counts sharks. She conducts underwater visual censuses, (UVC), which are separated into two methods.

In the belt transect census, a diver fins along a straight line, counting sharks observed within a fixed distance on either side.

In the stationary point count, the diver remains fixed, and counts sharks within a perimeter.

Christine wants such surveys to state whether they used non- instantaneous counts, where sharks entering the survey area during the count are included, or instantaneous counts, where sharks entering the survey area during the count are excluded.

There's concern that using the non-instantaneous method may result in shark populations being over estimated, although I'd suggest there's the possibility that results could be managed by expanding or contracting the survey area.

For example, Palau is renown for its regular shark encounters, yet there would be very differing results if you counted sharks in a radial area of 0 - 10m, than in an area of 10 - 20m, even on the same dive.

While other variables, such as current, are noted, they have no bearing on results. If no sharks are seen, mitigating circumstances aren't taken into account.

But if researchers are conducting UVCs, it follows that they expect to see sharks, and as perimeters can be set to as little as 8m, with no baiting allowed, then they must be expecting healthy populations. At some locations at least.

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In order to measure the impact of trade on the global shark population, Shelley Clarke counts what's left when their fins pass through the world's largest market in Hong Kong.

Utilising accepted scientific practice, she measured and weighed the dried fins, then converted the data 'backwards', from end product to live creature, to calculate the total catch. Her calculations of 26 - 73 million are three to four times higher than the Fisheries Observer Agency figures, but way short of 'The Magic Number'.

"Once my estimates of shark kills based on the fin trade were published, I naively thought that the 100 million figure would go away. I think if my number had been higher than 100 million it would have, but since it was lower, some NGOs did not want to backtrack and suggest that things had improved. The fact that 100 million is still commonly used is a clear lesson that impact matters more than facts in some cases. I have absolutely no insight into what has made people inflate the number over time."

Indeed although Shelley's data is the most up to date and accurate available, and is accepted within conservation, as she herself recognises, it's also ignored. Some groups don't want to admit they're pushing the wrong number. Worse still is the misinformation employed in the breakdown of that number.

The majority of sharks are not killed for their fins. The IUCN, the International Union for Conservation of Nature, states that bycatch, sharks caught unintentionally in the targeting of other fish, accounts for 57.9% of the total catch, nearly twice the 31.7% of sharks caught intentionally by direct commercial fishing.

You'd never know this from the on message 'churnalism' that's endless recycled across shark conservation's social networking sites. Some groups don't want you to know. When I posted the IUCN breakdown on the Shark Savers facebook wall, my post was deleted. So much for raising awareness.

A self righteous crusade to end the fin trade and finning glosses over the fact that bycatch is the major threat to sharks. And bycatch implicates us all, not just the Chinese. Asian countries have the largest fishing fleets, so if shark conservationists really want to beat them with a stick, then be it fins, finning, or bycatch, they've got all the justification they could ever need.

It's worth considering that the initial publication of 'The Magic Number' was back in 1997 in 'Time' magazine. That's a minimum of 100 million sharks for every one of the subsequent years. It follows that this could be considered a sustainable annual yield, with sharks taking between six to eighteen years to mature and reproduce.

If the 100 million annual catch had a dramatic impact on populations as conservationists claimed, it would be reasonable to expect that 'The Magic Number' was numerically, and commercially, impossible to sustain over this period of time. It seems 'The Magic Number' has become a self defeating argument. So are shark conservationists crying wolf?

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Director Rusty Armstrong and Eli Martinez, editor of 'Shark Diver' magazine, had been touring shark diving hotspots and had experienced the embedded conservation message at every turn.

So it only took one dissenting voice from a shark fisherman for them to consider the subject from a fresh perspective. 'The Shark Con' is a feature-length documentary that raises interesting questions about the importance of sharks to conservationists. Producer Steven Pavón told me;

"When we started this film so many people told us there were no sharks, yet everywhere we went diving we always got sharks in good numbers. So I started digging. I really want the public to know what is going on with these conservation groups, who take donations for research, and see what percentage actually makes it to shark research."

"When you are talking about the eco business, you're dealing with people who don't want to have a solution, because problems, drama and crisis are their bread and butter."

One of the criticisms levelled against the Shark Con team was that they produced a procession of salty looking dudes who fished sharks for a living, and would naturally resent regulations that would impact on their livelihoods.