Sea Cave Making

Mendocino's sea caves are world famous.  The whole coastline is like swiss cheese with notches, caves, holes, arches, and tunnels.

Sea kayaking through arches and into sea caves on the Mendocino Coast of California.  

When walking on the coastal headlands, one can see the alluring arches, tunnels and dark cave entrances.  On calm days, kayakers get the opportunity to paddle into the caves.  And of course some of us push the limits a little - surfing through arches and playing in rowdy sea caves.

Have you ever wondered "How are sea caves formed?"  This winter, we have had lots of cave making days.  This inspired me  to share a little bit about how sea caves are formed and some photos and videos from our wet and wild winter of 2018-2019.

Winter storm surf crashing into the Noyo!

How are sea caves formed?

The simplest answer is that sea caves are formed by erosion.  Coastal erosion is also referred to as coastal process.  Check out this website for more information on coastal processes including wavelogy.  

To specifically see how sea caves, arches, and sea stacks (stumps) are formed check out this video.

In the winter, winter storms often generate large swells that roll into the Mendocino Coast.  Usually we have one large swell event per winter (25 feet plus waves).  This winter, we seem to be having these events every other week.

Awesome winter storm surf on crashing into the Mendocino Coast.

It is very exciting.  We can hear the surf and feel its energy from our house - which is about a mile from the ocean.  When you get close to the ocean, the power of the large surf is AWESOME!  While watching waves roll through the bays and hearing and feeling them crash onto the headlands, one feels the energy permeate through your soul.

As sea level is rising and we are having higher tide, the effects of large surf in the winter months during our king tides is significant.  One could speculate that it is increasing the rate of coastal erosion.  We often comment that it is another cave making day.


 Then we see the effects - logs and jetsam are chucked up on the headlands.  At the Point Cabrillo Lighthouse, one of their informational signs was annihilated.  

Landslides and rock falls are happening.  We have not seen any arches collapse., but it is a possibility.  To the south of us in Point Arena, a huge sinkhole with a cave leading to the ocean has opened up.


In Noyo Bay, the Sinkhole Cave is one of our favorite paddling spots.

Sea Cave Kayaking on the Mendocino Coast.

Last week, we were walking on the coastal headlands and saw muddy water flowing out to sea.  Moments later, we discovered a large landslide occurred on the back wall of the Sinkhole Cave.

Landslide into the back side of the sinkhole cave on the North Side of Noyo Bay.

Today, I was walking and saw that it has slid more.  The ground around it is cracked and looks to be ready to slide further.  This week, we are forecasted to get over 5 inches of rain.  The weekend the swell predictors are in the 30 plus foot range.  I'd say that it is likely to slide more.

Coastal erosion on the Mendocino Coast of California.

These are exciting times.  The next time that you kayak on the Mendocino Coast, things could be quite different.  Sea caves could have more head room and potentially there maybe more rocky rubble in passages that are clear.  We of course have a couple of spots in mind that we would like to see some moving and shaking.

Probably best not to do any sea cave kayaking for a while.  This summer when things have dried out and the swells have mellowed out, we will be back in Mendocino's sea caves and let you know what we find.