The Tidepooler

Dock Fouling 101: What Is It and Why Would I Do It?

Tide pooling is one of my favorite activities (if you couldn’t tell), but especially this time of year, the best tides are often very early in the morning and it can be difficult to take advantage of them. Other times of the year, there simply aren’t very many good low tides and you may not get an opportunity to visit your favorite tide pooling spot for weeks or months at a time. 

To remedy this, some tide poolers have taken up dock fouling. This activity is similar to tide pooling, but you are searching for marine creatures on the underside of docks instead of on rock shorelines. This article will run through the basics of dock fouling so that you are equipped for you next adventure. 

What is dock fouling? 

Dock fouling is different things to different people. If you are a boater, fisherman, or live on the water, then dock fouling is the annoying algae and other marine life that grows on the bottom of a floating dock. However, if you are a tide pooler or marine life enthusiast, dock fouling is the act of looking at this growth on docks and trying to find life there. This doesn’t involve swimming, but instead peering over to see what’s growing on the side of the dock, either on your feet, on your knees, or lying on your stomach.

Dock Fouling vs. Tide pooling 

Dock fouling and tide pooling are sister hobbies; you’ll see many of the same creatures in both areas. However, there are some key differences that might sway you one way or the other. 

The main benefit of dock fouling over tide pooling is that it doesn’t depend on the tides. Fouling is only going to grow on docks that float up and down with the tides (like boat launch areas or fishing docks), not on fixed docks (like piers). So when the tide inhibits you from seeing animals on the rocks, the ones that live on the docks are still accessible. 

While dock fouling allows you to see many of the same species you will in the tide pools, there are several that are exclusive to one or the other. You are more likely to see open water fish dock fouling than you are tide pooling while sea stars, sea urchins, and other echinoderms much prefer the rock shore and are seldom, if ever, seen on the docks. Several nudibranch species seem to prefer the docks over the tide pools, but this may have more to do with their food sources or how low the tides are. 

What to expect when dock fouling

There are several things that are helpful to keep in mind before you go dock fouling. Here is a list of just a few.

• Don’t expect it to be scenic: Unlike the tide pools which are often sweeping, open seascapes, dock fouling isn’t particularly scenic. While the animals may be just as neat, the surroundings are usually a boat ramp or public dock that is covered in bird droppings, smells like gasoline, and is often busy with boaters and/or fisherman. The animals are worth it, but don’t expect scenic, peaceful surroundings 
• Not suitable for kids: Tide pooling is a great activity for kids, but dock fouling really isn’t. Busy, dirty docks with no railings aren’t very suitable for energetic kids. Besides, the animals are likely to be farther away, less active, and not as large as the ones in the tide pools, where you’ll find animals that are more interesting for kids. If you’re kids are a bit older or really interested, you might be able to keep their attention, just make sure they don’t fall in!
• It can be difficult to find things: Finding marine life while tide pooling or dock fouling is all about training your eyes to known what to look for. Like tide pooling, dock fouling has a bit of a learning curve to be able to spot tiny nudibranchs, fish, and other animals. The image below features a Spanish shawl seen on the side of a dock, but did you notice the northern kelp crab hiding in the kelp?

• Prepare to get weird looks: Dock fouling isn’t a super common activity, and those doing it are likely to earn funny looks from those launching boats or fishing. Decide before you go that you don’t mind looking like a crazy person. 
• Hard on your knees and back: In order to see the animals clinging to the side of the dock,  you’re going to have to get down on your knees or stomach. This not only means that your clothes will probably get dirty, but that your knees, neck, and/or back might end up hurting by the end of the day. Many people bring knees pads or towels to kneel or lay on to remedy these problems. 
• Be aware of boats and fisherman: If you’re dock fouling in a public boat launch area or on fishing dock, be aware of boats or fisherman. They are entitled to use the space as well and you may have to move for a boater who has no other spot to tie off their vessel. Be kind and understand that it is a shared space. 

Where to go dock fouling

It’s harder to find good places to dock foul than to tide pool. This is mostly due to the lack of public floating docks (most are private) and the practice of dock scraping, where private owners or the local government will scrap the bottom of docks to prevent fouling from growing for one reason or another.  

However, there are several places where this is not done and are thus great for dock fouling. I’ll make a separate post about specific dock fouling locations, but for now, you can search for floating public docks, usually in the form of fishing docks or boat launch areas. There are several projects on iNaturalist focused dock fouling where you can see where others have made observations and find locations. If you live in Washington state (where dock fouling has a bit of a following), this site is great a resource for dock fouling information and areas.

One final note, make sure not to go dock fouling illegally, i.e. on private floating docks. There are plenty of docks that aren’t scraped that are private residences or belong to boating companies. Don’t trespass onto these docks. If you find a place that looks promising, just ask the company or owner of the dock. If you’re kind and explain what you’re doing, they may be oblige you.