Yucatán: Largest Ever Congregation of Whale Sharks

Take a boat off the Yucatán Peninsula this week and you will see the most astounding sight. The water is filled with the gentle giants of the sea, all meeting to feast on little tunny fish eggs. Whale sharks are there in their hundreds, with an estimated 420 of them forming the biggest aggregation. A second group are even further out to sea.


The Mexican Caribbean is home to the whale sharks, which can stray as far north as the Gulf of Mexico and the Southern coast of the USA. While sightings are rare up there, a glimpse of them off the Yucatán can be guaranteed, if you know where to look.

Yet their numbers this year have taken locals and scientists by surprise. Usually they are solitary creatures, meandering their way through the ocean alone or in schools no more numerous than a dozen. The hundreds in the Yucatán Afuera aggregation have brought researchers flocking to record this amazing event.

Flyovers have taken in the scale, with aerial footage and measurements; while scientists in boat are weaving amongst the whale sharks, collecting samples of food in nets.


This is the world's largest fish, with adults reaching lengths of 40 feet (12 meters); yet they are utterly harmless to human beings. Their diet consists mainly of plankton, plants or very small fish. Though, as the recent feeding frenzy shows, mackerel eggs are apparently a favourite.

Meanwhile, over in the second aggregration, in the Yucatán Cabo Catoche, it appears that shrimp and small crustaceans were there main draw on the menu.

Whale sharks swim with their mouths open wide. As water funnels through, they filter out the good stuff and keep it in their stomachs. The rest is channeled out through their gills.


Despite their huge size, whale sharks are not aggressive. They have a reputation for being incredibly docile and moving extremely slowly through the ocean. They will generally ignore human beings, as we aren't food; though well-fed ones are more inclined to be playful. They will happily allow people to swim alongside them and will even give them a 'ride', towing them through the water.

They live up to 100-150 years. Each one has a unique pattern of spots on its back, acting like fingerprints to identify them.


Mike Maslanka, biologist at the USA's Smithsonian Conservation Biology Institute, explained the significance of this find. "With two significant whale shark aggregation areas and, at the very least, one active spawning ground for little tunny, the northeastern Yucatán marine region is a critical habitat that deserves more concerted conservation effort."

His colleague, Lee Weigt, head of the Laboratories of Analytical Biology, added, "Having DNA barcoding is an incredibly valuable resource for this research. It not only allowed us to know what exactly this huge aggregation of whale sharks were feeding on, not readily done from only physical observations of eggs, but it also revealed a previously unknown spawning ground for little tunny."

It is worth noting that whale sharks are considered 'vunerable' by the International Union for Conservation of Nature. This is due largely to over-fishing and trophy hunting. The greatest predator for whale sharks being, of course, humans.

Why You Shouldn't Approach a Shark Giving Birth

The blogosphere is currently agape with sensationalist writing - shark attack in the waters around Cancun! A woman has been bitten! Flee the sea! Reading these, and the newspaper stories that inspired them, would have anyone convinced that the Caribbean Sea is now grey with hordes of smirking sharks staring down tourists in the hope of a snack. It's patently time to inject a little truth into the reporting.


Bull Shark - one of the suspects (Photo: Brian J Skerry)
I'll admit that, when I first heard about this, I was skeptical. Despite the headlines, this just doesn't happen here. In fact, we have already covered the highly improbable scenario of a fatal shark attack, in the waters off Cancun: Sharks in the Mexican Caribbean. So was this incident making liars out of us? Not really, no.

The official verdict on the circumstances has yet to emerge, as it's been too soon. However, we can piece together the likely events from eye-witness reports and the telling of the victim herself. Nicole Moore is currently recovering well in Cancun's Hospiten. Despite rumours to the contrary, all of her limbs are intact and likely to be functional in the future. She is perfectly able to explain the situation herself.

Even her father, talking to the National Post, stated that, "Some of the reports have been grossly exaggerated." While the director of the hospital, Dr. Italo Sampablo, has commented, "We've not had this kind of incident here previously."


Cancun's Caribe Park Royal
Nicole is a 38 year old nurse, and a mother of two, who traveled to Cancun with a party of ten fellow Canadians. They all hail from Orangeville, Ontario, and came here to celebrate the 50th birthday of their fitness instructor. Her husband and two daughters stayed home. On Monday, Nicole was amongst a crowd of people playing volley-ball on the beach. It was an activity organized by Cancun Caribe Park Royal hotel, where she was staying. As the sun crept up towards noon, coupled with the exertion of the exercise, she decided to go into the sea to cool off.

As to what happened next, the Mexican authorities are waiting on their report until they can establish that it was definitely a shark and not a barracuda. However, eye-witnesses state that it was definitely a shark. The fact that none of them can identify which species of shark would suggest that no-one present was an expert in the field. However, specialist knowledge was not required to see what was happening: the shark was giving birth!


Tourists clambered around to take photographs or simply to get a good look at the wondrous event. After all, you rarely get to see something like this outside of the Discovery Channel! Nicole was one of them. Also attracted by the sudden furore were lifeguards, who quickly assessed the situation and blew heavily on their whistles to clear the water. Jetskis were mobilized to get between the shark and the tourists. However, before they could reach them, the shark snapped.

Unfortunately, Nicole was closest to her jaws at the time. She suffered injuries to her arm and thigh, but never lost consciousness. She is a nurse. She instructed those around her on how best to stem the blood and apply First Aid, until the paramedics could reach her. Ten minutes later, she was in the hands of professionals and en route to hospital. She has undergone surgery, but is now awake, chatting with friends and looking forward to going home. It's believed that she will be able to return to Canada in a week.

Meanwhile, the shark, having delivered her warning, disappeared into the open ocean. Presumably to find somewhere more peaceful to deliver her young. Four lifeguards, on jetskis, searched the area immediately afterwards and were unable to locate her. As a precaution, the Cancun Caribe Park Royal beach was red-flagged for the rest of Monday through to yesterday. It is unknown whether it will remain so today. There have been no more sightings anywhere along the Yucatan coastline. Some people are defying the ban and going into the waters anyway.

Sharks in the Mexican Caribbean

One of the most frequently asked questions about the Caribbean Sea is: will something eat me? You can almost see the vision playing out behind people's eyes. There they are, meandering along the white sands in their new, trendy beach outfit. Admiring looks follow them, as they enter the water, sunlight gleaming on their tanned, sea soaked skin. The crystalline Caribbean Sea stretches out for miles of turquoise, each wave sparkling like gems. Beautiful, stunning. And then a shark eats them.

That's one way to ruin a lovely daydream. Let's see if we can get it back on track. The truth is that the above scenario is all very feasible and extremely likely to happen, with the exception of the ending. There are sharks around the Yucatán Peninsula, as evidenced by the fact that the word shark itself is Mayan in origin. But the chances of them eating you range from highly unlikely to extremely improbable. You are far more likely to get hit by lightning than attacked by a shark, let alone eaten by one.

Most shark attacks occur because of mistaken identity. Sharks haven't got good eyesight and therefore may mistake you for a tasty snack. However, the oceans around the Yucatán Peninsula are crystal clear. The shark is more likely to be able to see you very clearly and therefore won't bother you. You are more likely to see a shark by the coral reefs, but even then it will be a rare sighting. No-one has ever died of a shark attack in the Yucatán, though someone did get bitten in 1941.

In April 2008, news spread across the internet about a vicious shark attack in Cancún. While it is true that there was a dead man and there was a shark, the reality wasn't quite as the social panic would have it. The whole story is recounted in more detail over on Annet van de Mortel's blog. The short version is that he got drunk and drowned. The shark was nowhere near him at the time.

The trouble is that everyone has watched 'Jaws' and so sharks are now forever categorised as 'very dangerous to humans' in our mind's eye. In reality, out of 360 known species of shark, only a handful are dangerous. The Great White Shark, the Tiger Shark, the Bull Shark and the Oceanic Whitetip Shark are responsible for the majority of fatal attacks on humans worldwide. By majority, we're talking about 5-15 attacks globally each year, often in self-defense. The other 356 species of shark, for various reasons, are simply not interested in you. Even amongst the dangerous ones, it's rare for them to attack; and divers have been able to swim right alongside without becoming dinner.

So which sharks are swimming in the oceans around Mexico? Loads of them. It's where a lot of those species live. However, you're probably mostly interested in the 'baddies'. Let's look at them:

Great White Shark. This is the species made famous in the 'Jaws' film, however it doesn't visit Mexico. The closest it comes is in the northern Gulf of Mexico, bothering those in the American South. How to avoid being eaten by them: come to Mexico.

Tiger Shark. This one does live here! However, the chances of it attacking are ridiculously unlikely. For a start, they've been hunted close to extinction, with the World Conservation Union (IUCN) having it listed as 'nearly threatened'. While the big game hunters are out getting their trophies, the tiger shark consequently not out there in any great numbers. Even should one turn up, the likelihood of it attacking is very low. Nevertheless, it should be treated with respect. How to avoid being eaten by them: look them straight in the eye, so they know they've been seen and so can't ambush you.



Please note the complete lack of any tiger sharks eating the divers in the above video.

Bull Shark. These sharks do live in the Mexican Caribbean. Again they are the targets of big game hunters and are listed by the World Conservation Union (IUCN) as 'Near Threatened'. However, they've been responsible for only 17 fatalities worldwide, since records began, none of which were in Mexico. How to avoid being eaten by them: punch them in the snout to avoid close contact.

Oceanic Whitetip. This is the shark of shipwreck legend. It lives well off-shore and descends upon sinking ships for its supper. Though it does live in the Mexican Caribbean, it's nowhere near the beach. It's in the really deep waters right out at sea. You are more likely to encounter it on your plate, as this is the shark that commercial fisheries catch for sharkmeat. As a result, it is listed by the World Conservation Union (IUCN) as "vulnerable". How to avoid being eaten by them: punch them in the snout to avoid close contact.

So that's the four biggies taken care of. In the extremely rare situation that you see a predator, then look it in the eye and punch it in the snout, if it gets too close. That's all. But the majority of sharks in the Mexican Caribbean really aren't that interested in you. Your most likely shark sighting will be with a nurse or whale shark, both of whom eat plankton.

Back to the daydream...

... meandering along the white sands in their new, trendy beach outfit. Admiring looks follow them, as they enter the water, sunlight gleaming on their tanned, sea soaked skin. The crystalline Caribbean Sea stretches out for miles of turquoise, each wave sparkling like gems. Beautiful, stunning. So they have a little swim, then get out of the water to lie back on the sun lounger. Their biodegradable sunscreen is reapplied between sips of rum and sangrita; and all the world is great.