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Marine Life & Conservation Blogs

Sharks the Ocean’s Greatest Mystery – Part 2

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Sharks are an incredibly significant animal in human culture of both the past and present, they are an animal that have been embodied in our culture for millennia. They are represented in formats such as books and clothing, but most notably in our TV and films, which is where a large portion of their negative reputation stems from. A popular TV representation of sharks comes from Discovery Channel’s ‘Shark Week’, and I believe sharks are possibly the only animal on our planet to have an entire week dedicated to them every year. However, despite this, we still know more collectively about the surface of the Moon and Mars, about Galaxies outside of our own, and even about animals that have been extinct for millions of years, than we do about sharks.

Sharks are our Ocean’s top predator, and they represent just how little we know about our blue planet. We have put more money into exploring outer space than we have exploring our seas and whilst many people call space the final frontier, I believe the final frontier is our Oceans. There are people that have lived in space for over a year, yet we aren’t able to stay underwater for more than a few short hours, and with each dive, scientists are discovering something new in the deep sea, giving us a better understanding of our oceans and the top predator that lives within them.

What we do not know

It is easier to talk about what we do not know and the implications of not knowing it, we still don’t know where most shark species mate or give birth, knowing this would accelerate conservation efforts for sharks in a huge way as these areas could then have realistic protections placed on them, allowing us to preserve key stages of the Sharks life cycle.

Marine Biologists have stated that the discovery of a White Shark breeding ground would be the holy grail of Ocean Science, but the only reports of White Sharks mating come from a handful of sightings from Fisherman and Sailors, so these cannot be used as an official record.

We know that Sharks mature late in the same way as us humans, it is estimated that some species are estimated to not be sexually mature until their late 30’s and 40’s, which means that these species are at extreme risk of disappearing due to fishing, as they aren’t able to replenish their numbers fast enough when put under extreme fishing pressure. There is a lot of debate over whether Sharks mature at a certain age or a certain size, for example it was estimated that White Sharks mature at four metres in length, however, in South Africa in 2017 a female White Shark was killed by Orcas, and it was determined that she was either immature or hadn’t mated, as there was the presence of a Hymen.

We are also still unsure about the impacts of human activities on Sharks and how losing Sharks, or their habitat, would affect the habitats and environments on land, environments in which we depend on for our survival.

What we do know

New Shark discoveries are made every year, and scientists are predicting that in the next 15-20 years we will be entering the golden age of ocean and shark discoveries. We already know that sharks are the oceans top predator and we have determined that they affect the very mechanics and functions of the Ocean, if we were to remove them, we would be putting the worlds ecosystems at risk of collapsing. Sharks are an integral part of the balance of the oceans, they help by controlling populations of other species, if we were to lose sharks, species such as turtles would have an increase in population, therefore leading to more seagrass being eaten, which is a prime food source for many animals. Thus, other smaller animals would not be able to feed, and their population would decrease, also the decrease of sea grass would affect us humans on earth as the oceans plant life helps to absorb carbon dioxide and create oxygen, and actually up to 75% of the oxygen we breathe is created from the oceans.

We know that some Shark species have complex social relationships that aid in their survival, although this has only been observed in a handful of species. Lemon Sharks form bonds as pups and hunt together in the shallow mangrove swamps of the Bimini Atoll, and will learn and hunt together and learn vital skills needed in their future survival. Hammerheads are possibly the most famous for social interactions as they form huge schools off places such as the Galapagos Islands and it has been observed that the more dominant females swim in the centre of the school and display for the males.

Some shark species, such as the Zebra Shark, have been known to mimic other animals. Zebra sharks are born with stripes (which fade as they get older) and they have the second longest tail (after the Thresher Shark), this helps them to mimic the highly venomous, White-Banded Sea Snake in order to trick predators into avoiding them, they have even been reported to mimic taking a breath at the surface like a sea snake would do.

It has recently been discovered that Greenland Sharks are now the longest lived Vertebrate on our Planet, they are believed to be able to exceed the age of 500, with females not reaching sexual maturity until they are around 150 years old. This was discovered by examining special proteins in their eyes that do not degrade with age. Determining age and sexual maturity are crucial for understanding and managing shark populations as knowing what age a Shark can breed will allow us to gauge what protections a species needs.

It has recently been discovered that female Whale Sharks are able to store sperm to use over a period of time, this is in order to ensure their chance of reproducing, even without recently mating. This is a huge advantage for conserving the species, as Whale Sharks are classed as an endangered species and so, with the number of whale sharks declining, this ensures the species can continue. Along with this, Whale Sharks have also been found to be pregnant with up to 300 pups, and these pups can be at different stages of development due to the staggered use of stored sperm.

Of all things we know there is one thing that is certain, a Shark, no matter the species, is unique and worth more to our world alive than dead. In the next blog we will explore the threats that Sharks face and how we can help Sharks through the tough times ahead.


Follow Donovan on Instagram at www.instagram.com/donovans_reefs

Donovan is a Divemaster who currently works as a Shark Diver at Blue Planet Aquarium based in Ellesmere Port. Donovan’s passion lies with Elasmobranch’s (Sharks & Rays) and this passion has led him to work in South Africa with White Sharks for a short period. He also believes that education through exposure is the best way to re-educate people about Sharks. Follow Donovan at www.instagram.com/donovans_reefs

Marine Life & Conservation Blogs

Sharks: The Oceans Greatest Mystery – Part 3

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Sharks are a truly incredible animal that have evolved and shaped themselves to be the perfect predator which, in turn, has shaped our oceans and the animals that live within it. Sharks have existed on our planet for up to 400 million years and throughout that time they have become one of the most numerous top predators on our planet, they have lived through 5 major extinction events when many other species died out. Sharks have been doing something right all this time, but at this very moment sharks are facing a threat that is so powerful that it is literally changing the face of our planet, and that force is Humans, it’s us. Sharks are being killed at an unprecedented rate, a rate of unimaginable scale. Recent studies by scientists have shown that since 1970 we have reduced Shark & Ray populations by a staggering 71%.

What threats do they face?

Sharks worldwide are currently dealing with a huge array of issues which is putting the whole group at risk. Sharks are being killed for their Fins, Oil, Teeth/Jaws and other members of the group, such as Manta Ray’s, are killed for their Gill Rakers and wings.

Firstly, let us talk about what is potentially the most inhumane form of animal harvesting, Shark Finning. This is the practice of removing a Sharks Fins, usually whilst the animal is still alive, and then discarding the rest of the animal back into the Ocean. The Shark is usually still alive throughout the whole process and the animal usually dies from drowning or blood loss on the sea floor. Shark fins only account for around 2% of a Sharks average body weight which means that 98% of the animal is merely tossed back into the ocean, 98% of the animal is just simply wasted. Now this begs the question what are Shark fins used for? Well, they are used in an Asian dish known as Shark Fin Soup, now Shark fin is tasteless, which means that the fin only adds mere texture to a Chicken or Pork flavoured broth which further begs the question, why use Shark Fin and not something else to add texture. Well, the soup serves more as a status symbol and it is known as the food of emperors and kings, those who can afford and serve Shark Fin at a banquet or party are revered as wealthy.

Sharks are also harvested for traditional medicine, where it is believed that by ingesting Shark parts such as their cartilage or liver, it can give you a Sharks “magical” powers and abilities. The most common rumour is that Sharks do not get cancer, and by consuming Sharks you can also become immune to cancer. This is of course false; Sharks do in fact get cancer and with recent additions of pollutants and chemicals into the oceans from human activities, sharks get cancer now more than ever, along with a whole host of other ailments. This means that by eating Sharks you are actually more likely to catch illnesses and ailments such as Mercury poisoning, due to the fact that Sharks hold a large quantity of such toxic substances in their bodies.

Aside from Shark finning, they are also at huge risk of becoming caught in nets and on lines as Bycatch, this means that they get caught despite not being the targeted species. For example, Sharks are commonly caught on Tuna hooks or in Tuna nets. Unfortunately, in these instances they tend to not even have their fins removed and, in this case, the whole animal is wasted. The sharks are usually already dead after being brought up due to the amount of time they have sat on hooks and usually die from exhaustion or drowning. Sometimes Sharks are killed in sport fishing tournaments as game fish, where people will go out on Shark fishing days and many Sharks will be killed for the chance of beating a previous record.

Sharks are also at risk of habitat loss, in the same way as Jaguars and Macaws in the Amazon, and Elephants in Asia. Human activities such as fishing, expansion, pollution, mining and Global Warming are all threatening Sharks Habitats. Flapper Skates, which are also known as Common Skates, are now Critically Endangered around the UK due to trawling damaging the egg laying sites for this species. The Bimini Islands, which are famous for the presence of a Lemon Shark Nursery, were in trouble a few years back with plans for demolishing a section of the Mangrove Forest on the island, to make way for a Golf Course. Thankfully it wasn’t successful, but if it was it could have put the Lemon Sharks at extreme risk as this is an area needed for the beginning of the lemon shark’s life cycle.

Another factor putting sharks at risk, is the amount of plastic pollution and pollutants in the water. Plastics can block the digestive system of plankton feeding Sharks and Ray’s such as Whale Sharks and Manta Ray’s, and discarded fishing gear such as nets can entangle up Sharks and other aquatic animals. The amount of fishing being done in the oceans also puts sharks at risk from their food supply disappearing, as humans fish the oceans, we are inadvertently removing the fish stocks that Sharks rely on for their survival.

Sharks & People

Sharks are an apex predator in the World’s Oceans, and it may seem far-fetched to believe, but we depend on Sharks more than you might think. Let us start with fish, currently 10-12 percent of the world’s population relies on the Ocean’s fish for their diet and survival, and Sharks help to keep fish stocks healthy by eating sick, injured or diseased fish and holding the toxins and diseases in their bodies until they die, this is why Sharks have such a strong immune system. With Sharks hunting these fish, it helps to keep the stocks healthy and means the fish that we catch and eat won’t make us sick.

Sharks also play a vital role in the Planet’s oxygen cycle, the Ocean essentially acts as a giant blue lung taking in Carbon Dioxide from the air, seagrass beds and plankton then absorb the Carbon Dioxide and release it as Oxygen back into the atmosphere. If Sharks were to disappear then other animal stocks would explode out of proportion and eat all of the sea grass and/or plankton and the oxygen cycle would be hindered. An example is, if Tiger Sharks were to disappear, then the Turtle population would rapidly increase, allowing the Turtles to eat all of the Seagrass, which would mean we lose a key component of the production of our oxygen. Along with plankton, seagrass helps to produce 75% of the Oxygen we breathe daily. Seagrass Meadows also store more Carbon than any Forest on land making them one of the most productive habitats on our Planet.

How can we be better Ambassadors to Sharks?

It may seem like there is not much we can do, but you would be surprised to hear that there is in fact a lot that we can do to help Sharks. Sharks have been tarnished with a hugely negative reputation, a reputation that can make protecting them difficult. The problem is people are told their whole lives that Sharks are mindless killing machines and that if you go in the Ocean, you are likely to meet your timely demise, but we now know that these stories are literally just that, stories. One of the best ways of protecting sharks is to help people better understand them and all it may take is a simple conversation, a conversation where you can debunk myths, a conversation where you can change their perspective. Jacques Cousteau once said, “People protect what they love”, and this saying holds a lot of weight. People will protect sharks if they love them, and the only way to allow people to love them is for them to first understand them, and understanding first comes through education. If people love Sharks, then the whole cycle starts again with them going out and telling people about Sharks. If you are Diver and or, Underwater Photographer, then you can share your experiences and imagery with people, which will allow their perspectives to shift, and you would be surprised to find out how beneficial Social media can be for Sharks, as it’s a place where you can share your images and stories to a very wide audience across the globe.

Another way to help is to not buy Shark Fin Soup or any Shark products, it may be tempting to buy a Shark tooth necklace or Shark in a jar when on holiday, or even to try Shark Fin Soup, but this will only feed the problem, if we can do this then, when the buying stops then the killing can too.

Something that has been realised recently is that Sharks are worth more alive than dead and over a Sharks lifetime, it can bring in many millions of Dollars through Echo-Tourism, compared to the couple of dollars it will bring into a fisherman if the animal is killed. Thankfully, areas that were once Shark fishing hotpots, have turned to becoming areas where Shark populations have exploded, due to an influx of Divers from across the globe going to see Sharks alive and healthy. Places such as Raja Ampat, The Maldives, and The Galapagos Islands have put protections on sharks and in doing so attract divers to these areas where Sharks are protected, with divers going to these areas only further helps and funds the Protected area and allow the work to continue.

A final thing you can do is to write to your Local MP about needing larger and stronger Marine Protected areas, with stronger protections from commercial fishing. As it stands there is less than 0.5% of our World’s Oceans that have complete protection from commercial fishing. Scientists have stated that for our Oceans to be protected, we need at least 30% of our Oceans to have complete protection for Sharks, Fish and other marine mammals, which will, in turn, allow our Oceans to stabilise themselves.

There is still a lot that you can do and if you do just one of these things, you could help change the fate of Sharks and allow them to continue thriving and shaping our oceans for millennia to come.

So that’s it, a deep dive into Sharks, our Oceans Greatest Mystery. A look into their biology, behaviour and secrecy. I hope after this you come away with a better understanding and appreciation for this incredible group of animals, I hope after this you now look at a Shark and see not a monster, but an animal that is incredibly misunderstood and one that not only keeps our Oceans healthy, but also our whole Planet. Sharks are a key component in our survival, and with our help they can continue to be our Oceans Greatest Mystery.


Follow Donovan on Instagram at www.instagram.com/donovans_reefs

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Marine Life & Conservation Blogs

Take an immersive dive below the waves off the Welsh coast using 360 VR: Common Spider Crab (Watch Video)

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A week-long series from Jake Davies…

Below the waves off the Welsh coast, there are a range of species and habitats that can be seen. However, you don’t have to venture too far from the shore to see them or don’t have to leave the comfort of your home. Using 360 videos provides an immersive feeling of being below the water and encountering many species and habitats from diving one of the most important habitats and species that aren’t often seen whilst diving. For more of an experience of being below the waves, the VR videos can be viewed using a VR headset.

Take a VR dive just off the shore and explore what can be found within the shallow waters of a sandy beach. Fish can be founding cruising amongst the seaweed and numerous crustacean (Crabs, lobster, prawns, shrimps) species can be found walking around the seafloor. Common Spider Crabs (Maja brachydactyla) are one of the largest crabs species found along the coast and during the early summer, they aggregate in large numbers to moult which allows them to grow.


Follow Jake aka JD Scuba on the YouTube channel @Don’t Think Just Blog.

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Explore the amazing triangle of Red Sea Reefs - The Brothers, Daedalus and Elphinstone on board the brand new liveaboard Big Blue.  With an option to add on a week at Roots Red Sea before or after. 

Strong currents and deep blue water are the catalysts that bring the pelagic species flocking to these reefs. The reefs themselves provide exquisite homes for a multitude of marine life.  The wafting soft corals are adorned with thousands of colourful fish. The gorgonian fans and hard corals provide magnificent back drops, all being patrolled by the reef’s predatory species.

£1475 per person based on double occupancy.  Soft all inclusive board basis, buffet meals with snacks, tea and coffee always available.  Add a week on at Roots Red Sea Resort before or after the liveaboard for just £725pp.  Flights and transfers are included.  See our brochure linked above for the full itinerary.

This trip will be hosted by The Scuba Place.  Come Dive with Us!

Call 020 3515 9955 or email john@thescubaplace.co.uk

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