Tides are the rise and fall of ocean waters along the shore. They are caused by the gravitational pull of the sun and moon. Tides can be great for water activities, but tides also pose danger, especially if they change when you are not expecting them to.

Certain seasonal or weather conditions, such as storm surges, storm tides, and king tides can cause tides to become even more extreme than they usually are. (Read more on different types of tides and tidal phenomena here.) Tides also change hourly, daily, and monthly.

Tides can move up or down the beach by up to 10 meters throughout the day.

For example, the Bay of Fundy between Nova Scotia and New Brunswick fills and empties a billion tons of water twice a day during each tide cycle. It has the highest tides on earth, and looks virtually unrecognizable from high tide to low tide.

Hopewell Rocks at low tide. Photo by Jenni Konrad

Hopewell Rocks at high tide. Photo by Jenni Konrad

Tides affect coastal areas, such as beaches and estuaries. Estuary water levels are influenced not only by ocean tides, but also by the shape of the coastline, the ocean floor, the wind, and the depth of the water. Believe it or not, even some lakes have tides, though they are very minor.

The principal lunar semidiurnal tidal constituent. Colours show tidal amplitudes (in cm). Photo by R. Ray, NASA Goddard Space Flight Center

How to Stay Safe during Tide Changes

The easiest way to stay safe in tidal areas is by knowing how to read a tide table. You should always check tide tables before you head to the beach for the day. Tide tables offer predictions that are usually very accurate.

However, tides can be unpredictable at times and can deviate from tide tables due to factors like local weather and wind patterns. Keep in mind that the number of times a tide changes in a day varies depending on location.

If you’ve walked along the beach to another bay, cove, or rocky outcrop during low tide, you can be cut off by the water and stranded as the tide comes in. If there are no alternate ways of leaving the area, you may be in very serious danger.

Photo by Dennis Jarvis

It’s always a good idea to seek advice from a lifeguard or local about tides. It’s safest not to explore any tidal areas alone. If you do decide to go alone, make sure you let someone know where you are going and when you plan to be back. If you’re able to, bring a cellphone with you in case there is an emergency.

The safest time to swim is during a slack tide, which happens in the hour preceding or following a high or low tide. It’s safest to swim in waves with shorter intervals, which are calmer and less dangerous.

Photo by Phuket@photographer.net

While you’re at the beach or in the water, stay alert and be conscious of your surroundings. The tide may move faster than you realize, particularly near sand bars and through gullies.

How to Stay Safe in Tide Pools

You’ll want to check a tide table to determine when tide pools will be exposed. You should also make a note of when the tide will come back in. Make sure you allow yourself enough exploring time before the tide changes by beginning your adventure 20 to 30 minutes before low tide.

Never leave children unattended in tide pools.

Waves can suddenly crash over the rocks with more than enough force to knock over a child. A strong enough current can sweep a child out to sea. Don’t turn your back to the ocean. Notice where the rocks are wet to determine how far into shore the waves are reaching.

Photo by Photo by Joël de Vriend

Rocks can be slippery from seaweed or algae, while barnacles and shells can be sharp enough to cut your skin.

If you do end up with a bleeding wound, try to keep it out of the water. When you cut yourself in the water, your body is exposed to whatever pollutions or contaminants may be present and you risk infection.

Watch your step near tide pools. Wear good footwear to avoid injuries and only step on dry, bare rocks or sand.

Walking with caution will do more than just keep you safe. It will also keep the creatures in the tide pools safe. Be aware of where you put your foot to avoid stepping on animals. If you can, observe tide pools from the edge.

Photo by Sue Talbert Photography

It’s exciting to find a hermit crab or starfish in a tide pool, but resist the temptation to pick them up. This will cause the creatures stress. Removing them from their hiding places will also expose them to predators, the sun, or other people.

Certain animals can actually harm you if you touch them. Creatures like crabs, sea urchins, and jellyfish do not want to be handled, and they will make their feelings known with a hard pinch or a sting.

The only thing you should pick up and remove from a tide pool is litter.

Marine life can choke on, swallow, or become ensnared in garbage, and it can damage ecosystems. If you see trash in a tide pool, take it with you when you leave and dispose of it. The creatures will thank you!

Photo by Pexels

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