How to Put a Shark in a Deep Trance – A Diver’s First Hand Experience

how to put a shark to sleep

There is a way to lull a shark to sleep… to put them in a deep trance for a few minutes, just enough so you can pet it or let others gently touch it and feel its sandpaper-like skin. It is called tonic immobility: a state in which the shark is placed in a natural state of paralysis. It is an instinctive reaction when stimulated a certain way. It does not harm them. Science still doesn’t know the purpose of this reaction, but it is a truly fascinating thing.

Calming a shark and putting it to sleep is something I have done a hundred times, but I never get tired of it. I love sharks, and when I hold them in their trance-like state, there is a great fascination that I feel for these incredible creatures.

It all starts with choosing the right shark to handle. A great subject is the Caribbean reef shark. When diving underwater, you have to be completely calm and find a shark that is relaxed and does not seem aggressive. One that is swimming lazily and slowly. It may seem more intimidating, but the bigger ones are usually the more stable and willing. Additionally, females are almost always the easiest to entice.

When I spot one, I extend a hand to feed it, usually with a herring. Although it may seem like free food, not all sharks can be lured to it. Others who do not want the attention would simply swim away. The shark should be willing to take the food before you are able to pet it. When it comes close enough, I start petting it under the snout. That’s where the magic happens.

Under the shark’s snout are freckle-like dots called ampullae of Lorenzini. It is so sensitive, that if you twitch just a single muscle, they would be able to sense it. Because it is overly sensitive, it is also easily stimulated. So when you gently touch and massage it, they feel an overwhelming sense of stimulation that limits their mobility. Their bodies fall into a completely relaxed state. You can touch and move them around without much struggle. How long does this trancelike state last? About a few minutes. I have once handled a shark for 30 minutes in this state. If I want them to snap out of the trance, I simply stop stimulating and let go. Then they go back to their business like nothing happened. It is truly an amazing phenomenon.

I usually do this in front of an audience, not to draw attention to myself but to show them how fascinating sharks are. Tonic immobility is just one of the interesting facts about them and there are so much more people ought to know.

To lull a shark to sleep requires a great amount of diving experience and extensive knowledge about their behavior. I don’t encourage inexperienced divers to do this when they encounter a shark. What I do encourage is for everyone to get to know these amazing creatures. I hope more people will love them and save them, in the same way that my fellow divers and I do.

Cage-Diving with Wild Bears

cage diving bear photos underwater

I went to Kurile Lake in Kamchatka, Russia after watching about it on a television documentary. I got fascinated because bears come there every year, as they consider it the best place for them to find food or take shelter. Aside from that, the lake is the largest breeding ground for red salmon—one of the best of its kind—in the whole of Eurasia.

I knew that no one had tried taking pictures of the bears underwater, since it would be strenuous and dangerous. Knowing the obstacles that I will go through, I still made a go for it. I went to a shop and asked for a box for my photo camera, telling the assistant my intentions. He reacted as if I was completely insane.

Working with a predator means having one foot in the grave; one tiny mistake can lead to a giant mess even if you work with one easily at first. Because of this, we had a special cage built to prevent direct contact with the bears. What I had to do was watch from the bottom up every time one got up on its hind legs.

I was that desperate to get a shot. I spent hours soaked in the freezing cold water, and it thrilled me whenever a bear came near. There were times when I got really close to them, and I tried my best not to ruin the moment. However, they turned from pretty creatures to beasts as soon as I got in the water, chasing me, hunting me down like I was food.

Bear attacks really are fatal. There are more chances of being killed by one than being killed by a lion, tiger, leopard and shark combined. Looking back, fulfilling this dream of mine—taking shots of bears underwater—almost caused me my life. It was something exciting and memorable, but it was a bad idea. Never in a million years would I recommend what I did to anyone.

PADI Course Director

What is a PADI Course Director?

Course Directors are a step up from the typical PADI Master Instructor. The Course Director is responsible for teaching the PADI IDC (Instructor Development Courses), along with other more advanced, instructor-level dive training. The PADI Course Director is highly skilled, and can be considered an expert in the field of scuba diving. In fact, this is the highest rating that can be held with regards to recreational scuba diving.

Should You Apply?

If you are passionate about diving and are eager to make money helping others, I encourage you to apply for a seat in a CDTC (Course Director Training Course). Space is limited, and as such the application process is moderately competitive. If you have at least 250 successful logged dives, are a certified EFR Instructor Trainer, and meet the other eligibility requirements, you have a decent shot. If you have teaching experience, or have assisted a Course Director in Instructor Development Courses, be sure to put that on your resume, as this is highly desired.

PADI Continuing Education Flow-Chart

Cave Diving In Madagascar – Stories Worth Telling

Similarly to many awesome stories, this one begins with a simple phone call from my life-long friend Adalrik. “Eis, I met a girl [Hannah] who has had over 20 successful dives in the caves of Madagascar, she’s planning her next trip in two weeks and I already told her that you were going with me.” I usually like to have more notice, especially for a long distance trip – not to mention all that goes in to preparing for a cave dive. But I’m not one to turn an opportunity like this down, so I agreed. The next two weeks consisted of us gathering as much intel as we could on the caves, while we bought tickets, made travel and hotel arrangements, and mentally prepared for this experience of a lifetime.

Adalrik had close contacts with a Hungarian geologist that had been employed in Madagascar for many years – a valuable friend indeed! He was able to make copies of a number of his own personal geological maps, which also included survey data of caves and their dimensions.

Fast forward two weeks and a day and we arrived at Ivatao International Airport. Keep in mind, this is not an American airport. I was expecting some nice air conditioned building where we would calmly wait in line until it was our time to speak with customs officials and have our passports stamped. Boy was I wrong.

The plane lands. We walk directly onto the field and must have walked at least a quarter mile to the location for arrivals. There were no lines in the arrival hall. There were two employees working at the center of the building that were responsible for taking the Ivatao International Airportpassport and stamping it. Unfortunately, stamping a passport is a long, drawn out procedure in Madagascar. I had to stand around in the chaos for nearly 25 minutes before I heard someone scream out some sounds that resembled my name. Ah finally – now I just have to fight my way back through the crowd to retrieve my stamped passport and I was on my way. An African airport – such pandemonium!

Our hotel was located in a city that seemed almost third-world. Dirt roads – if you can call them that – lacked any streetlights or signs. Quite a culture shock. The inside of the hotel was surprisingly very nice. Almost felt like I was in the twilight zone once I entered as it felt out of place from the street it was located on.

The next morning me and Adalrik decided to try a dive on our own without Hannah, as we were there a day earlier than she was. Using only the geological maps, Google Earth, and a small tidbit of information we were able to gather online on the days leading up to our expedition, we told our driver where to go. This particular cave was in the middle of the desert. Cactus all around us, and aside from this hidden water source, there was no other water in site. Once we arrived we were both pretty psyched to jump right in. We checked the tanks – Carbon Monoxide levels were good. We geared up and gently eased our way into the water.

Within a few minutes we realized that there wasn’t any opening wide enough to fit through that would lead us to a cave system. After nearly twenty minutes we found a small hole that was just barely big enough for one person to slide through. This small tunnel continued until it pretty much closed off with debris. We each took turns trying to remove rocks from the opening to clear a path, but this didn’t seem to get us anywhere. After a while we decided to cut our losses and get back out of the water.

We continued on to the second potential site about one kilometer to the east. Walking down the steep depression was quite a task with all the gear still on. The anticipation was killing us so we didn’t want to waste any more time than we already had. Finally I could see the pool of water. The water was crystal clear with a slight blue tinge. It was unreal. From the surface it looked as if it was about 10 meters deep, but this was only an illusion due to the clarity of the water, it was actually close to 50 meters.

Towards the back of the submerged cavern was a huge underwater tunnel that dropped down moderately fast – probably close to a 40° angle. Swimming around the edges of the tunnel, we could marvel the intricate patterns made over thousands of years, and just couldn’t be replicated – this was simply one of a kind. On the floor we could see huge cayman skulls, which Adalrik quickly captured with his underwater camera. Unfortunately, he is not an experienced underwater photographer so the picture wasn’t the best. This was alarming for a few moments as we were unsure whether we were swimming around in a cayman skulls in underwater cavecrocodile’s den but that fear soon passed out of excitement for our new find. We later found out that these were most likely fossilized. After reaching nearly 200ft of registered depth as measured by our line, we decided to start heading back. Along the way we spotted a number of other tunnels branching into multiple directions, which gave us hope that we could have a much more successful dive the next day with Hannah, as our Carbon Monoxide (CO) levels were approaching 40 ppm and we had already both gone through our spare tank at this point. Upon reaching the surface, we were both enthralled at what we just got to experience. It was quite possible that we were the only two people that have ever actually been at this site, as cave diving in Madagascar is not popular at all. We hypothesized that this would be the perfect starting point for the days ahead, as there were a handful of unexplored tunnels, at least one had to connect with the underwater cave system. Swimming through the tunnels for the duration of our trip confirmed these expectations.

Over the next few days I will continue to document the most memorable experiences of this trip. If I had the chance, would I go back to Madagascar to cave dive? Absolutely. Each underwater cave system is unique. This uniqueness and all the characteristics and small details that you learn to take note of is largely dependent on the location of the cave. A cave dive in Florida compared to in Mexico compared to in Madagascar is a completely different experience. Not only does underwater visibility vary from dive to dive, but the color of the rock, the soot, and the intricacies of each tunnel and underwater cavern vary tremendously down to the smallest details.

CCR Cave Diving

ccr cave diving - totally possible

I would consider myself an enthusiastic rebreather diver. I also love caves. If someone can come up with a better way to combine both of these obsessions in one activity, please enlighten me. Until then, closed circuit rebreather (CCR) cave diving will continue to keep me occupied.

There are plenty of people that will tell you Florida is not the ideal locale for CCR cave diving – whether they argue it as being too shallow, or the tunnels too narrow, I can personally tell you that this is simply not true. As I’ve preached before, when it comes to cave diving, or scuba diving in general, maintaining awareness of your surroundings is crucial. With a bit of forethought, some skill, and a love for the sport, the utilization of your diving machines can be incorporated into many cave diving scenarios.

Whenever someone uses the “its too shallow” argument, I always bring up the fact that with a low set point, and adequate bail out planning leading up to the dive, you can spend the entire time floating around underwater. With proper technique, you can experience the entire cave in only one dive. Keep in mind this depends on the size and complexity of the caves and tunnels. Florida has a wide range of caves that are well suited for rebreathers.

Sure, I’ll acknowledge that the majority of dives can be accomplished with OC alone, though you have to admit that CCR is well ahead of the pack with regards to gas logistics and cave diving of extended durations. Long story short, if you already cave dive, and you are experienced with CCR diving, combine the two of them together. Have no idea where to start when it comes to rebreathers? Have a look at this. Enjoy!


Cave Diving Documentary – Worth the 53 Minutes

Cave diving gets a bad rap because of the dangers associated with it. Sure, cave diving can be dangerous, but it can also be fascinating. I thought I’d post this video up from Youtube. It does a great job at providing you with the overall picture of cave diving. You’ll see some beautiful underwater footage along the way. If you really are interested in cave diving, try not to get all caught up in the media hype. The media is only going to report when things go wrong while cave diving. There are substantially more successful dives than their are those that end in injury or other forms of tragedy. Hope you enjoy.

Debunking the Age Old Myth of “Size Matters” for Flashlights

NIGHTSTICK is an industry leader in professional lighting solutions. Recently, it launched its flagship product the MT-100, which has taken the market by storm. NIGHTSTICK’s MiniTAC MT-100W family is known for its typical four-flashlight nightstick flashlightconfiguration. What’s amazing about this particular flashlight model is that it is a top quality product while being relatively small and lightweight. The MT-100 houses the brilliant CREE LED flashlights with a deep parabolic reflector and measures less than 5.6-inch. This peculiar design means that the light produced from this flashlight is a tight, long beam which is ideal for long distance illumination.

The first warning bell that might ring in the mind of most customers is that due to its short size, the model must compromise quality. However, this is not the case as the NIGHTSTICK MT-100 family boasts a high level of functionality and can be flicked on or off in a moment by using the tail switch. The body of these flashlights is made from aircraft-grade 6061-T6 aluminum which has not only made the model light but also virtually indestructible. On top of the MT-100 family being chemical and water resistant to an astonishingly high degree, it has also survived the fall test from a height of 2 meters.

All of the four NIGHTSTICK MT-100 series flashlights are powered by a set of batteries and are protected by a limited warranty. The MT-100, MT-110, and MT-120 models all feature a sturdy metal pocket clip. The MT-130 (Gooseneck) takes this a step further and features a removable clip-on magnet that makes it ideal for hands-free use. Undoubtedly, the most exciting feature of the Mini-TAC MT-100 family is the sheer amount of concentrated light the flashlight gives off. Even though it is a very small model, it is incredibly powerful and has successfully debunked the age-old myth that the size matters.

The SafetyBlu Inspection Kit – Is it Worth It?

safety bluThe SafetyBlu SB-450 Inspection Kit has taken the market by storm. It can be described as a lightweight, easy-to-carry, high-intensity LED flashlight. What separates the SB-450 kit from other tools in the industry is that it can locate fluid leaks quite early on. This not only reduces the number of injuries miners or scuba divers sustain but also reduces fluid consumption by 5-7% annually.

The FluidSafe technology of the SB-450 kit assists in the early detection of leakage and removal of liquids used in hydraulics if a haywire fluid injection penetrates the human skin. When a suspected area is illuminated under SafetyBlu’s powerful blue LED light, the fluorescent glow highlights the exact location of the injected material, which makes it easier for medicinal practitioners to deny or confirm if the hydraulic penetration took place. Thus, it is fair to say that it also aids in the surgical removal of excess fluid.

The usefulness of the SafetyBlu flashlight extends to fluid leaks in hydraulic system hoses, fittings, and seals. This can result in the prevention of catastrophic mishaps.

The LED is housed in a robust aluminum body which has been anodized. This makes the SafetyBlu corrosion resistant and increases the life of the instrument. The SafetyBlu derives its power from a NiMH battery. This battery is of rechargeable nature and provides up to 1.5 hours of regular usage between charging cycles.

The SB-450 kit also includes AC chargers, a belt that can support the kit, DC chargers, and illumination-improving glasses. All of the components mentioned above are packaged in fitted compartments in a sleek carrying case.

Evolution of Batteries

These days, more and more emphasis is being laid upon the retention of a battery’s charge. Recent advancements in the field of batteries have made it possible to power electric cars, orbiting satellites, and other electronic devices with potent batteries. On a lower scale, cameras and other small technological gear can now last much longer between charges. If you’re underwater taking pictures of a coral reef or cave diving and find your way hundreds of feet below the surface, the last thing you want is for your camera to die on you.

We can think of the Battery Series as a five-part infographic spectrum that details how each battery works. The Battery Series also includes other important aspects like the big players in the market, the core materials in the manufacture of batteries, and how probable battery advancements may better the world. For part 1 of the Battery Series, we will be looking at just the basics of a battery along with a brief history of battery technology.

Battery Basics

Batteries work on the principle of converting stored chemical energy into usable electrical energy. There are three main components in every battery:

(-) Anode: The negative electrode that aids in the release of electrons.

(+) Cathode: The positive electrode that accepts these released electrons.

Electrolyte: The medium that surrounds the electrodes and facilitates the movement of charges from one electrode to another.batteries series

The Evolution of Battery Technology

We have come a long, long way from the earliest batteries developed. These designs focused primarily on the production of electrical energy, while nowadays, there are many other important factors to consider such as power output, weight, and cost. A concise history of batteries is stated below:

Voltaic Pile (1799)

Named after its pioneer, the Italian physicist Alessandro Volta, the first voltaic battery was developed in 1799. It was the first ever battery to be produced. It could easily transfer power to a circuit. The voltaic pile made use of copper and zinc as electrodes, while a brine-soaked paper served as the electrolyte for this battery.

This battery also has a significant place in history as it debunked the widely accepted theory that only living beings could create electricity. The world of science honored Volta by using his name as the SI unit of measurement for potential difference (voltage).

Daniell Cell (1836)

John Frederic Daniell completely solved the “hydrogen bubble” defect of voltaic piles. The hydrogen bubble defect had caused the voltaic pile to have a short lifespan. However, the Daniell cell fixed most of the problems associated with voltaic piles by using copper pot (which was filled with a CuSO4 solution) and was further immersed in a container that had sulfuric acid and a zinc electrode.

The electric potential of the Daniell cell became the basis for the unit for potential difference i.e. one volt.

Lead-Acid (1859)

The lead-acid battery was a revolutionary device as it was the first battery that could be recharged. It was developed by a French physicist named Gaston Planté. Lead-acid batteries took the market by storm due to two main reasons:

  1. They were very economical to produce.
  2. They could supply high surge currents if needed.

Nickel Cadmium (1899)

Waldemar Jungner invented nickel cadmium batteries. They are now commonly known as wet cells because they used a liquid electrolyte. These batteries paved the way for modern technology, even though they have fallen out of favor in the market recently due to cadmium’s toxicity.

Alkaline Batteries (1950s)

Alkaline batteries are the ones that we are most familiar with. Popular battery brands like Energizer and Duracell make use of alkaline batteries to power common household devices. They are preferred because they offer great value for money, and even though they are generally of a non-rechargeable nature, they can be charged again by making use of a specially designed cell.

The alkaline batteries that we see today were first invented by Lewis Urry. Urry used manganese oxide and zinc as electrodes, while the electrolyte became the basis of the name of the invention as it was potassium hydroxide (an alkaline solution).

Nickel-Metal Hydride (1989)

The nickel-metal hydride battery employs a hydrogen-absorbing alloy. As these batteries steer clear of cadmium, they are more environment-friendly. Nickel-metal hydride batteries are commonly used to power digital cameras and power tools. They were even used in hybrid cars like the Toyota Prius.

It took two decades worth of investment and efforts from Volkswagen AG and Daimler-Benz to spawn the first NiMH batteries. They have been commercially available since 1989.

Lithium-Ion (1991)

Lithium-ion batteries have taken the market by storm. They were first released by Sony in 1991. Li-ion batteries are preferred because they have a high energy density (which means they can store more charge in less space). The uses of Li-ion batteries range from lithium cobalt dioxide (LiCoO2) cathodes batteries being used to power laptops and cellphones to lithium nickel cobalt aluminum oxide (LiNiCoAlO2) batteries which have been used to power cars like the Tesla Model S.

The Rechargeable Battery Spectrum

The selection of a battery is subject to a plethora of factors. One of the most significant battery selection parameters is cost. Other important factors include the fitting and usage of rechargeable batteries.

However, there are two other factors that can change the landscape of the battery industry. The first factor is the specific energy capacity of a battery, while the other is the specific power. This means that even though Li-ion batteries are dominating the industry today, should there be a battery in the future that is cheaper and has more specific energy and power, it could easily dethrone Li-ion batteries as the number one choice for most manufacturers.

New to Scuba? Don’t Consider Cave Diving Just Yet

A cave diver myself, I’ve always been interested in the abilities and overall mindset of other seasoned cave divers. Whenever I help instruct cave diving courses (or any scuba diving course for that matter), I look implement my first-hand experience if at all possible and relevant to the task at hand. In many instances, we practice after hours in around 20 feet of water in an Olympic sized pool at a local university. When you’re under the water and the sun is no longer providing you with light, that pool does surprisingly well as replicating any cave diving experience.

scuba diving in 20 ft pool

You may become disoriented; you may have trouble seeing directly in front of you, etc. Navigational mistakes are probably one of the most common to occur, and when it comes to cave diving, can be dangerous or even deadly. Maintaining your composure during these situations is of paramount importance. Mistakes happen not only to beginners but seasoned cave divers as well. Maintaining composure is easier said than done when you’re trapped underwater, possibly hundreds of feet below the surface and the only way out is back the way you came in.

When I say beginner, it is important to note that ‘beginners’ should be experienced scuba divers before the thought of cave diving even crosses their mind. The diver should have mastered their skillset in various ways, including situational awareness underwater, communication skills with other divers, equalization techniques, and understanding pressure change and air consumption levels. Once you feel you have learned pretty much all there is to know when it comes to diving, only then should you consider cave diving.