Courtesy of WOWSA, Huntington Beach, California.

Lewis Pugh explains what he has to do when swimming above the Arctic Circle and along the frozen coastline. “We throw rocks into the water near the shore. Leopard seals hide under the ice shelf waiting for their prey to jump into the water, so we can see if the leopard seals come out. If the seals are there, I do not get in.”

Swimmers have a variety of ways and means to protect themselves against creatures that strike the most fear in the world’s oceans including sharks, box jellyfish, hippopotami, and crocodiles.

The top 10 most potentially dangerous creatures in the open water for swimmers are below:

1. Polar Bear
Found in the Arctic. They look cute, but they are extremely dangerous. They are one of the few animal species that will hunt a human. They do not fear man and can move very quickly.

Countermeasure: Immediately get out of the water, into an escort boat, and move quickly to safety.

2. Nile Crocodile
Found in many rivers and lakes in Africa. They are patient. They wait. They are ambush predators. It is difficult to see them – because most rivers and lakes are murky. Not many people survive a crocodile attack.

Countermeasure: Immediately get out of the water, into an escort boat, and move quickly to safety.

3. Hippopotamus
They kill more people in Africa than any other animal, other than the mosquito (malaria). A bite from a hippo is a serious wound.

Countermeasure: Immediately get out of the water, into an escort boat, and move quickly to safety.

4. Leopard seal
They are frightening looking animals with razor sharp teeth found off the Antarctic continent. They bark a blood curdling hiss when swimmers get near. One moment they will kill a penguin and drop it in front of a swimmer as a gift. The next moment they are trying to bite human legs.

Countermeasure: If in the water, immediately get out of the water, into an escort boat, and move quickly to safety.

5. Great White Shark
A well-known apex predator found in most oceans is very dangerous, but a surprising number of people survive great white attacks.

Countermeasure: Immediately get out of the water, into an escort boat and move quickly to safety.

6. Box Jellyfish
Some species are among the most venomous creatures in the world and are found off the Australian coast, but they are invading other waters around the world. A sting can be fatal.

Countermeasure: Almost impossible to avoid in certain times of the month just before sunset and in the night. Upon being stung, get immediate help.

7. Orcas or killer whales
They can handle themselves well against the Great White Shark. Enough said.

Countermeasure: Immediately get out of the water, into an escort boat and move quickly to safety.

8. Sea snakes
Air-breathing aquatic snakes have some of the most potent venom of all snakes. Some have gentle dispositions and bite only when provoked, but others are much more aggressive and teeth may remain in the wound.

Countermeasure: Immediately get out of the water, into an escort boat and move quickly to safety.

9. Needlefish
These slender fish have long, narrow jaws filled with multiple sharp teeth and can jump out of the water at high speeds over the decks of shallow boats, especially when attracted by light at night.

Countermeasure: Immediately get out of the water, into an escort boat and move quickly to safety. Do not wear anything that illuminates or reflects light (even moonlight).

10. Piranha
Known for their sharp teeth and a voracious appetite for meat, the total number of piranha species is unknown with estimates ranging from fewer than 30 to more than 60.

Countermeasure: Follow the steps used by Martin Strel during his Amazon River stage swim [story to follow].

There are other predators and creatures for open water swimmers to be cautious of, including homo sapiens, however, humans are visitors to the marine world where its natural denizens must be respected and protected.

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