09/06/2026
Guidelines for behaving when encountering sharks
Excerpt from the NDL textbook “Exhortation to the Instructor” .
Instructors’ clients often ask them the following questions:
"Is the risk of a shark attack a barrier to diving?",
"What should a diver do if they encounter a shark?",
"What can be done to minimise the risk of a shark attack or eliminate it altogether?"
Yes, indeed, there are cases of sharks attacking humans. This cannot be denied.
However, why and how often do such attacks occur?
So, what do we know about shark attacks on humans?
1. Attacks on divers are extremely rare
The vast majority of shark attacks on people are on swimmers or surfers, not on divers.
There are various theories as to why this happens.
Perhaps the swimmer’s jerky movements give the impression that this ‘animal’ is injured. There are suggestions that the shark mistakes the human silhouette for some other animal in its food chain, for example, a surfer on a board for a seal. In other words, a misidentification occurs.
2. Humans are not food for sharks
Scientists, and indeed anyone interested in this issue, argue frequently and at length about the reasons for these attacks. The nature of the attack suggests that they are most likely carried out by mistake.
Predators, when hunting, first kill their prey and then drag it away somewhere to eat it in peace.
Sharks, however, when attacking humans, in the vast majority of known cases, bite and swim away without killing or eating the person. From this, we conclude that humans are not the sharks’ prey for food.
It is difficult to say what a shark actually thinks, but we can say with certainty that humans are not its usual food.
Sharks do not feed on humans.
3. Shark attacks on divers are a reaction to human actions
Most cases of shark attacks on divers are the result of the divers themselves interfering with the sharks’ lives.
Any large animal is dangerous if provoked, especially if it is a wild animal.
In everyday life, a normal person would not feel the urge to ride a huge stray dog by suddenly mounting it, or to seek out and feed a wolf in the forest, and so on.
Underwater, for some reason, a number of people experience a sense of impunity, which often leads them to behave quite aggressively towards sharks: they try to stroke them, take close-up photos with them, grab their fins, feed them almost from the hand, and so on.
Such human behaviour can be perceived by a shark as aggression, which may trigger either flight or counter-aggression.
4. Statistics show that the likelihood of being attacked by a shark is extremely low
Millions of people swim in tropical waters inhabited by sharks every year. Worldwide, there are fewer than a hundred cases of shark attacks on swimmers per year. Of these overall statistics, attacks specifically on scuba divers are few and far between.
The risk of being attacked by a stranger’s dog in the city or being hit by a car at a pedestrian crossing is several times higher.
What can you do to minimise the risk of being attacked by a shark?
1. Never get too close to sharks
Do not attempt to feed sharks, stroke them, take photographs at close range, grab their fins, block their path, try to catch up with them or chase them.
When encountering a shark, a diver should always keep their distance to avoid provoking a defensive attack.
2. Do not make sudden movements and remain calm
When you see a shark, move as calmly and confidently as possible, without showing confusion, agitation or panic. Good buoyancy control is very important.
The predator must not see any nervous or frantic movements from the diver. Such movements demonstrate the diver’s fear of the shark or, conversely, may be interpreted by the shark as the diver preparing to attack it.
In the eyes of the fish, a human is a fairly large creature, likely strong, self-assured and dangerous.
You must not spoil this image with nervous movements and poor buoyancy.
3. Observe the rules of the partnership system
In the animal world, there is no concept of chivalry, fairness or honour in combat. A predator attacks the lone and the weak, without warning or a challenge, and when the risk of resistance is minimal.
A diver is a large and strong creature, and a group of divers is a pack of large creatures.
A predator will not attack a pack. Predators prefer solitary prey.
It follows that you must never stray from the group and, throughout the entire dive, you should swim with your partner within arm’s reach.
A diver must not be left alone. The group must remain a single unit throughout the entire dive.
4. Visual monitoring of sharks
When encountering a shark, you should always keep an eye on it.
You should not turn your back on a shark.
As has already been said, a shark is not a noble knight who will fight face to face. It will attack when its prey does not see it.
Swimming in a group and constantly keeping an eye on the shark’s movements significantly reduces the risk of an attack.
5. Having a professional guide
In areas where sharks may be present, it is advisable to use the services of a professional guide who knows:
• the dive site;
• where sharks might be found;
• how to minimise the chance of encountering these predators;
• how to behave if an encounter with a shark does occur.
In areas with high shark populations, it is recommended to have two professionals, one to lead the group and the other to bring up the rear, keeping a close watch on the sharks’ movements.
6. Wearing a wetsuit that covers as much of the body as possible
The less body odour, and the fewer any wounds, scratches or abrasions on the skin, the better.
Neoprene itself smells unappetising to fish. The more of the body’s surface is covered by a wetsuit, the less a person smells like a living creature.
*****
There is indeed a risk of a shark attacking a swimmer. However, with proper organisation and planning of the dive, this risk is reduced to virtually zero.
A responsible and cautious approach to underwater flora and fauna, an understanding that we are merely guests underwater, and adherence to the rules of the partnership system will ensure that sharks and any other underwater creatures do not display any aggression towards the diver.
*****
This was an excerpt from the NDL textbook “Exhortation to the Instructor”. You can purchase the book in Russian here https://www.avito.ru/sankt-peterburg/knigi_i_zhurnaly/nastavlenie_instruktoru_po_dayvingu_uchebnik_7562026816
The English e-book version is coming soon!
If you are an instructor or are planning to become one, you need this book.
If you’re an active diver, you’ll understand what and how professionals are taught.
Photo by Maori Dive Academy National Dive League Malaysia
