The rocky intertidal area, also known as the tidepools, is a favorite spot at Cabrillo National Monument. Each year over 350,000 people visit the tidepools, one of the best protected rocky intertidal areas in California. The best time to visit the tidepools is during the fall and winter months, when we get our great low tides during park hours. During spring and summer, the tide is usually covering the tidepools when the park is open. Please read Prepare for Your Visit to the Tidepools and Protecting the Tidepools before your visit so you will be aware of what to expect.
What is a Tidepool?
Tidepools are depressions in rocks that are formed over millions of years through a combination of biological, physical, and chemical processes. Tidepools need a rocky coastline to form. As the tide goes from high to low, pools of water are left behind among the rocks, forming tidepools. As the water moves away from the shoreline during a low tide, water and critters are trapped in these tidepools.
High vs. Low Tide
High Tide at Cabrillo National Monument's Tidepools. NPS Photo/A. Rosales
Low Tide at Cabrillo National Monument's Tidepools. NPS Photo/A. Rosales
It's Summer! Time to Hit Up the Tidepools, Right?
Well, yes and no. You can still visit our tidepool areas in the summertime, but you might not see too many tidepool creatures! Extreme low tides in the summertime happen in the middle of the night, making it impossible to see without any sunlight. Extreme low tides in the winter tend to happen in daylight hours! This means your best chance to see critters out and about in the tidepools is in the wintertime. While we still have low tides during the summertime, they are generally still too high for us to be able to see much else besides water. At Cabrillo, a 0.7 tide or lower will give you the best ability to explore the actual tidepools.
Late fall and winter are the optimum times for a visit to the tidepools at Cabrillo National Monument: unlike the summer months, when low tides occur in the middle of the night, the good low tides - including the outstanding negative low tides - in fall and winter occur during daylight hours when the park is open. A general rule of thumb is that the tidepools can be visited approximately two hours before low tide time (when the tide is receding) and two hours after (when the tide is coming back in). Please keep in mind that the tidepool area closes at 4:30 p.m.
Tide Tables - 2021
At Cabrillo, a 0.7 tide or lower will give you the best ability to explore the actual tidepools. There are two high tides and two low tides each day. Use this chart to find the times of the high and low tides.
Virtual Visit to the Tidepools
To ensure that current and future visitors experience and enjoy the healthy and diverse tidepools at Cabrillo National Monument, guidelines are needed to minimize the human impacts on organisms. To protect tidepool inhabitants, the following guidelines have been prepared:
Collection of any natural item, including living and dead organisms, shells or rocks, is strictly prohibited in any areas within or under the administration of Cabrillo National Monument. Similarly, approaching or engaging with any marine mammal is prohibited by the Marine Mammal Protection Act.
Many tidepool animals can be safely touched as long as it is done with great care and respect. A general guideline is to only touch animals as gently as you would touch your own eyeball. For example, anemones should not be poked and sea hares should not be squeezed.
No organism attached to a surface should be removed by force, however slight. Many animals, such as limpets, chitons, barnacles, mussels, seastars, and urchins are attached directly to rocks (permanently or temporarily) and using force to remove them would be harmful to them.
Animals that are actively swimming, moving away from people, hiding under rocks, or that resist being handled, should not be pursued or picked up.
Rocks should not be moved and should be left in their original location and orientation. Organisms living under the rocks have adapted to a certain environment, and rock-turning can harm them.
Nothing, especially rocks, should be thrown in any area of the park. Rocks can do great damage when they land in the water, and continue to do damage as they are tossed by wave action.
The following should not be introduced into the tidepool area: Containers (such as buckets or cups); nets, scraping, probing, or prying instruments (such as spatulas, trowels, knives, screwdrivers or sticks).
With your help, the tidepools at Cabrillo National Monument will remain a healthy environment for marine life, and will continue to be a prime example of this precious ecosystem for generations to come.
The tidepool area at Cabrillo is divided into several zones, where different types of animals and plants struggle to live. Depending on the height of the tide, some of these zones may not be visible. These zones are called the High, Middle, and Low zones.
The high or splash zone is located at the highest part of the tidepools. Here some animals can live with just the occasional splash from the high tides. Some of the animals you can find in the high zone are barnacles, limpets, chitons, crabs and mussels.
Take a closer look as you notice things on the rocks. Some of these creatures look dead or like fossils but they are all alive, trying to survive until the tide rolls back in. Please do not try to remove anything from the rocks as this will disturb or possibly kill the animals.
The middle zone is the zone between the high and low zones. There is an opportunity to see more critters in this zone compared to the high zone, due to the varying tides.
The lower zone is only available during the lowest of tides. Here you have the chance to find octopus, sea stars, nudibranchs, sea hares, spiny lobsters, urchins and various types of fish.
Other Tidepool Features and Resources
The tidepools are more than just the critters you can find in the water and between rocks. You can also learn about the geology that helped create the intertidal area that we see today. You can also learn about types of seaweeds, mammals, birds, plants, reptiles and the kelp forests that you might see along the Coastal trail.
Last updated: June 30, 2021