So, you have a bunch of large dock spiders crawling around your boat, boathouse, or even your home! And you need to get rid of them. Now.
These fearsome looking spiders are big with those long striped legs and huge oblong abdomens.
You’re sick of seeing them all over your boat at night.
You don’t want to walk into any more webs.
And your guests aren’t showing up to your yacht party anymore.
What should you do?
Get rid of them!
As hard as it seems, fishing (or wharf) spiders can be controlled greatly.
This can reduce their population so you don’t see them as often. If you have a boat or lakehouse, you’ll have dock spiders.
That’s a given. Any boat owner knows that.
But you can keep them in check with some easy, DIY home remedies.
In this guide, we’ll talk about:
- Why you have dock spiders
- How to naturally get rid of them
- How to keep them away from your boat, lakehouse, or boathouse
- And other DIY techniques for dock spider management and eradication
By the end of this page, you should feel comfortable with managing these pests.
They ARE beneficial to have, but not when they’re everywhere. Or if they’re getting spider poop all over your boat. Or if you’re afraid of spiders.
If you have any questions, you can leave a comment and ask me, as always.
Feel free to bookmark this page for easy reference later!
Sound good? Let’s dive in.
What’s a dock spider?
A dock spider is that dark brown or black spider that you commonly find near bodies of water. If you’re a boat owner, you’ve probably dealt with them numerous times already.
They can range in size- some are under 1 inch but others can span several inches. Their legs are always longer than their abdomen, usually 3 times the length.
So if the body is 1″, the legs are usually 3″ in length.
They’re considered to be a big spider.
And thanks to horror flicks, people are scared of them. Like the world needs any more arachnophobia, right?
You don’t want your guests panicking on board.
They like to nest on boats, docks, piers, wharves, or rafts and build their webs to catch the many different flying insects that hang around water sources.
Although they’re large and may look frightening, they’re merely an annoyance to most people and extremely hard to get rid of because of the breeding behavior and food supply.
Because they’re next to the sea, lake, or ocean, this provides them ample food and continues to attract more and more spiders to the area.
However, there are some things you can do to exclude, repel, and eradicate them from your boat. This should help get them in check.
The dock spider has a bunch of other nicknames and aliases that it’s known by.
Some of the most well-known aliases are:
- Fishing spiders
- Raft spiders
- Wharf spiders
- Wolf spider (mistakenly)
Since dock spiders are common in areas with large bodies of water, they’ve been named with dozens of titles- everything from folklore to wive’s tales.
Given their large size and alarming looks, it’s not surprising that they’ve gotten so many different names over time
These spiders are even present in modern-day cinema!
Dock spider vs. wolf spider
These two spiders are commonly confused for each other and the easiest way to tell the difference is to look at the eyes:
- Dock spiders have 2 rows of 4 eyes.
- Wolf spiders have 3 rows of eyes.
The easiest way to identify a dock spider is the large stripe that goes down each side of their entire body. The stripe can be multiple or just one line going down its sides and is usually pale in color.
Most members of the dock spider family (Dolomedes) have this pale stripe.
They come in many different sizes, shapes, patterns, and “designs.”
With over 100 confirmed species found all over the world, they’ve adapted to many different environments such as bogs, fens, and the high seas.
Other identifying features are the long legs, sheer size, and hunting habitat it prefers.
Dock spiders are up to 1 inch in length and legs over 3 inches. These are considered to be big spiders and are found all over the world globally.
Their head has 2 rows of eyes for a total of 8.
Their body is brown, black, or gray with markings on their abdomens. The legs are striped and evenly spaced with fine hairs.
Their entire body is covered with tiny hairs that are soft and water-repelling, which lets them literally walk on water.
They can skate around on water surfaces using the surface tension and run around as needed.
They also have the ability to go underwater by using their air supply in their tiny hairs.
When this happens, you may notice the spider turning silver or gray with a metallic luster or shine. They can control their swimming ability with precision and float up instantly.
This allows Dolomedes to inhabit the seas and catch prey.
Dock spider life cycle
Their life cycle is straightforward and consists of egg, spiderling (hatchling), and adult.
Similar to other arachnids, the dock spider spends its entire life alone and doesn’t cohabitate with other spiders- even of the same species.
Dock spiders have a life cycle just like most other spiders. The male and female mate once and then the female develops an egg sac. Mating rituals vary between species.
The female then carries her eggs around on the abdomen until they hatch. Spiders can lay up to 1400 eggs in multiple sacs. The eggs will hatch shortly after an incubation period and the spiderlings are off.
Female spiders will carry their eggs between their spinnerets.
They also may use their chelicerae (which are their fangs in their mouth) or their pedipalps to hold it. The spinnerets are at the rear of their body and they use this to move around so they can be mobile while they carry. They produce egg sacs in July.
The female will build a web for the sac and suspend it in midair. The eggs will hatch soon after. During this time, she defends them from predators.
Dock spiders are active and breed during the summertime in June.
When are they active?
Dock spiders are active during the night (nocturnal) and will come to hunt when they’re not likely to be eaten by their main predator- birds.
Birds aren’t active at night (most species) and will hide while the dock spiders come out to skim the water for food. They span out their legs to feel for insects in the water and eat them.
Even though they have poor vision, they can use their legs to detect vibrations to the slightest degree to distinguish between food and noise.
Are dock spiders dangerous? Do they bite?
Dock spiders can be scary because they’re huge and very quick to skitter around the water. Their hairy abdomens and dark legs also make them look pretty ferocious.
But in reality, all they want to do is eat. They don’t cause property damage and also are harmless to humans and pets.
You should still wear proper PPE when handling or going near spiders however because you could be mistaking them for something else that is dangerous and will bite.
Never assume it’s a dock spider at first glance.
Dock spiders will bite humans when provoked or threatened. Female spiders may also bite to protect their young.
But most dock spiders will run into hiding. The bite also doesn’t have enough power to break the skin, so a bite doesn’t harm most people.
However, sensitive individuals may have an allergic reaction to the bite.
Never handle or provoke one!
Why do I have dock spiders?
Water > flies > spiders.
You have dock spiders because you’re next to a stream, sea, river, ocean, pond, lake, or other body of water.
These attract aquatic wildlife and that’s what fishing spiders eat.
Since their food source is bountiful, you can expect that spiders will hunt the area to forage for bugs to eat and breed in the same place. It’s not possible to get rid of them completely, but you can greatly reduce their numbers by practicing some control techniques.
They spin tent-like webs to catch their prey, known as “nursery webs” which have a distinct appearance. They also fish on the water surface to reel in bugs.
Where are they found?
Dock spiders are found all over the world in boggy, wet, or damp areas with plenty of water.
Smaller bodies rarely attract dock spiders, as they prefer to have ample space for hunting. These are predatory insects that will hunt on the water surface rather than waiting around in a web somewhere.
They’re found all over the US, New Zealand, Europe, Canada, and more.
If you live near a marsh, river, stream, pond, lake, sea, or reservoir, you may have plenty of dock spiders running around.
They prefer areas with dense plant matter and artificial shelter, like forests, logs, outdoor showers, sheds, outhouses, cabins, dense foliage, boathouses, tall grasses, dense foliage, rocks, wood piles, and of course, sheds and outhouses.
Whether you have a boat or not, dock spiders can infest the home in isolated areas.
Do dock spiders infest homes?
They can make their way into your home but rarely will stay inside.
Similar to barn spiders, dock spiders can’t sustain themselves inside a typical household because there’s no water supply for them to hunt and there’s not enough food.
They need to be outside in the pool of water skimming on the surface to hunt.
They also have huge appetites, so even the most bug-infested household isn’t likely to provide them with enough insects to eat. Thus, dock spiders rarely infest homes.
What do they eat?
Dock spiders eat whatever they can catch in the water, or in their nursery webs.
They glide around on the surface to hunt prey that may be floating. They’re not picky about their food and will eat a variety of insects- whatever comes their way.
Fishing spiders can eat prey up to 5 times their own size, so they are definitely hungry spiders.
Some of their commonly eaten insects are:
- Small fish (goldfish, minnows, etc.)
- Aquatic wildlife
- Small reptiles (frogs)
The water helps them float around and gives them an unlimited supply of food.
Instead of a web, they use the water surface and extend their legs to detect slight vibrations on it.
This lets them detect and capture prey, just like how barn spiders, recluse spiders, or jumping spiders do the same on webs!
How to get rid of dock spiders naturally (home remedies)
Here are some tips and tricks you can do at home to control, manage, and eradicate dock spiders from your boat and property.
Use different techniques at the same time for the best results.
Find out what gets rid of them and scale it up.
Vacuum them up!
Use a portable vacuum cleaner to help quickly suck up any dock spiders you come across.
Obviously, this won’t get rid of the problem. But it can help out for those nighttime terrors when you’re outside trying to enjoy yourself. Any shop vac will do, as dock spiders rarely get larger than 3-4 inches.
You can use it to suck them up from cracks or crevices they run into or even right off their web.
Vacuums don’t work well for cleaning up webs because they get tangled up on the vacuum nozzle, so avoid using one to clean up the webbing.
But for spiders, they’re excellent for quick cleanup.
The spider may not die inside the vacuum bag or canister. So be careful when emptying it out.
You also want to empty the vacuum right after you catch the dock spider or else it can crawl out somewhere else on your boat.
Dish soap can be very effective against dock spiders when used correctly.
Dilute 2 tablespoons per quart of water and pour it into a spray bottle.
Use it to spray cracks and other areas where the spiders hide. It’s easy to spot them at night with a flashlight (and probably a bottle of spider killer).
Spray the solution in the daytime on their webs and hiding places. The thick surface tension of dish soap blocks their airways and drowns them. This may not work well on larger dock spiders.
But babies will be eliminated quickly. You can use any dish soap to do this. Add a few drops of peppermint oil for a lasting residual effect that repels them naturally.
Spray some Pine-Sol
The odor that’s emitted from the cleaning solution repels and drives spiders out.
If you buy a few large bottles and pour them out into smaller containers (use plastic storage bins) and put them around your boat dock to evaporate, the scent should keep spiders away.
Pine-Sol has changed their formula over the years. You’ll want to find one that contains actual PINE, as it’s the main active ingredient that does the repelling. The new formula is bad and doesn’t work like the old one. This makes it harder to get the right one.
Alternatively, you can spray the solution around areas that commonly have webs or you see active dock spiders hiding.
Cracks, crevice, dock lines, lift, and the roof, the slip, and poles are all good locations.
Reapply as necessary. Use as directed and read the label.
You can also soak cotton balls in the mixture and then place them in areas where spiders frequent.
The scent should repel them and keep them out. If your boat is airtight or well insulated, put a few inside the cabin when you’re away for some time. The scent will evaporate into the air and keep spiders from coming inside.
Even if spiders crawl in through vents or windows, the trapped Pine-Sol keeps them out. Just let it air out before you enter the next time you’re ready to take her out on the sea.
Putting up stringers around your boat poles and lines (and wherever else the spiders are making nests) can help keep them off. These are long pieces of cloth that float in the breeze so spiders don’t spin any webs on them.
They can help automatically repel pests without you having to use any sprays or compounds.
Although they don’t work for everyone, it’s worth a try because it’s an easy solution.
Sticky traps, boards, tape, or whatever you want to call it, work.
But they work amazingly well for dock spiders.
Put them in areas that spiders crawl over to get onto or inside your boat’s cabin. Think the slip, poles, dock lines, doorways, windows, rollers, support posts, ropes, vents, etc.
You can buy sticky tape or sticky boards depending on the surface you’re applying it to.
When a spider crawls over it, it’ll get stuck to it. Replace it as it gets full.
This isn’t a permanent solution because it won’t get rid of the spiders but only lessen their appearance.
These traps are super easy to use.
Spray dock lines
Dock lines can be sprayed with essential oils or commercial spider repellent if needed. These can be the “bridge” that spiders are using to get onto your boat.
So if you coat it with some kind of spider repelling liquid, it may keep them off. Additionally, you can put sticky tape or sticky traps
on the dock lines, which can also trap them as soon as they start crawling towards your boat.
Be sure that the spider spray you use is safe for aquatic wildlife, as many sprays aren’t.
This is why I suggest using only natural or organic ways to get rid of the dock spiders. If you choose to use a store brand, use as directed and exercise common sense!
Use a boat cover (spider netting)
Boat cover. Spider netting. Cabin shield. Whatever you want to call it- they work.
Get a cover that fits over your boat snugly and is fine enough to keep the smallest creepy crawlies from getting inside.
This is one of the easiest, and most basic, ways to completely protect your boat from dock spiders.
Even if they climb the dock lines, they still can’t get inside because of the poly material. This will prevent them from spinning webs, getting into hidey holes, and other spiderly things that they do.
Do be careful when removing the boat cover, because sometimes they crawl over it looking for a place to nest.
Don’t remove it during the night because dock spiders are active during that time. Wait until the day to take it off.
Hang fabric sheets
Apparently, if you hang those dryer fabric sheets (the really scented ones) around your boat, that can keep dock spiders (and other flying insects) away.
They can be hung anywhere you suspect spider activity.
Here are some key areas to cover:
- Within door frames
- Around windows
- Dock lines, ropes, and slip
- Within the cabin
- On the dock
- Around shrubs and dense foliage
You can stick them to the wall or crumple them up into a ball and stick them into small cracks.
Put them where you see dock spiders. I can’t vouch for the effectiveness of dryer sheets to repel spiders, but I’ve seen enough evidence to say that it’s somewhat effective:
Mothballs are nice, but they’re toxic when they build up fumes to toxic levels.
The main active ingredients mothballs use are naphthalene and paradichlorobenzene, which slowly seeps out of the ball. It slowly fills up space until it’s everywhere. Mothballs work best in small, enclosed areas so the smell doesn’t dissipate in the air and go away.
You can place a few in the cabin, storage boxes, crates, or other places where the air can build up. This should keep a whole host of critters away from your boat, including scorpions, chipmunks, and moths.
Have you ever seen a chipmunk on your boat?
Be sure to let the space air out before you go in or use it.
Avoid placing mothballs in areas where you’ll be spending time. Use as directed.
If you have lizards in the vicinity where you dock your boat, or if you’re not afraid of reptiles, get a new best friend and bring him along with your sails.
Lizards eat spiders with precision and can help bring down smaller dock spider infestations.
Many lizards will gladly hunt and scavenge for their next meal, including dock spiders.
Lizards such as geckos and chameleons, will eat them.
Of course, if you have those that are squeamish, then you have a problem.
Otherwise, carrying a few lizards onboard your boat is like having an army of workers that’ll eliminate any bugs for you 24/7.
You don’t need to do this forever- just when you set sail.
Lizards are also easy to keep and care for and you can remove them when you dock. It’s similar to how some people let their homes roam with monitor geckos to catch roaches and other bugs.
Eliminate flying pests
The reason why you have dock spiders in the first place is because of flying insects.
Spiders will appear where their food source is present.
They spin webs and catch flying bugs to eat them. Flying bugs frequent large bodies of water, which is likely where your boat is (right?). Water means flying bugs, which means spiders.
If you can find a way to bring down or control the flying insects rather than the spiders, then you can passively and indirectly get rid of the spiders.
Flying insects are easier to get rid of because there are a TON of different things you can do:
- Spray essential oils
- Use dish soap and water
- Hang flying insect traps
- Use sticky tape
- Spray insecticide
- Switch to yellow or sulfur lights
- Use citronella candles
- Use bug zappers
If you can bring down the number of flying bugs around your boat, the dock spiders will naturally leave as well. Once they see that there’s no food to eat, they’ll be forced to migrate off your ship to hunt for food.
Dock spiders rarely will leave far from their home site if there’s a bountiful supply of food to eat.
But once the population of bugs dwindles, they can’t sustain themselves and are forced to leave. This is the goal.
Get rid of the flying insects to get rid of the dock spiders. Cause a disruption in their food supply and they’ll go away permanently. Or at least not be seen as often.
Get rid of webs
Webs that are present on your boat will do nothing but cause you headaches when you walk into them at night.
Although these aren’t always the webs from dock spiders, they still attract other bugs to the area.
They’re a tangled, annoying mess that could be holding a bunch of dead flies all over them. And no one wants to walk into that.
The only way to truly eliminate the webs is to eliminate the spiders.
But until then, you can quickly clean up dense webbing using the following methods:
- Use a large canister vacuum to suck up any spider webs quickly
- Put on a pair of gloves and remove them manually
- Use a bucket of soapy water and a long stick. Use the stick to grab the webs, then dunk it into the bucket. The soapy water will kill any spiders or pests present.
Wash your boat
Washing your boat more often will help keep the spiders from nesting.
Do your rounds and remove all the debris and buildup every time you take it out. Keep it covered when you don’t use it. Boat washing is different for everyone, so I won’t tell you how to wash your boat.
The key is detail to remove the small food sources and hiding places spiders use.
Here’s a good video that goes over the finer points for new owners:
Keeping your boat free of webs is hard if you have a ton of dock spiders present.
There are some things you can do to help bring down the number of webs:
- Set up sticky traps around areas with high spider activity
- Use stringers on your slips, poles, and ropes
- Keep your boat clean and tidy
- Use a boat cover
- Use sticky tape on your dock lines
- Keep foliage, shrubs, and plants trimmed and pruned
Spray essential oils
Essential oils can be an effective way to repel spiders and keep them away naturally.
Some of the most effective oils to use for dock spiders are the following:
- Oils will come in varying concentrations and purities. They’ll need to be diluted with water before you spray, or else it’ll be way too strong.
Find a guide online for your specific oil and learn how to dilute it. Then spray it where dock spiders are present.
The nice part about oils is that they can be sprayed into cracks and crevices where other things can’t reach. The oil’s scent travels far into cracks and will dissipate to repel pests. Most oils are completely natural and safe.
But some may cause reactions in people and pets.
So read the labels, warnings, and use as directed. You’ll have to reapply in heavy winds or rain. If your boat gets wet, the oil will be washed off and the spider repelling properties will disappear.
Keep debris to a minimum
You can help reduce the number of dock spiders by keeping the area around your boathouse, boat, or property clean.
Dock spiders will leave behind large exoskeletons and nursery webs around plants, buildings, and other artificial structures.
You can do the following to help make your home less appealing to spiders overall, which may help keep them away:
- Get rid of large rocks
- Remove wood debris, woodpiles, or firelogs
- Keep sheds, boathouses, outhouses, and greenhouses clean and secure
- Get rid of any standing water or reduce it
- Get rid of shoreline plant or trim them and keep them tidy
- Remove all possible spider hideouts, crawl spaces, cracks, crevices, and other areas
What eats dock spiders?
Dock spiders have plenty of predators that will be glad to eat them. You can use this to your benefit to help bring down their population.
Some of their main natural enemies are birds, lizards, snakes, parasitic wasps, and even other spiders.
If you’re situated somewhere that has these species in abundance, find out how you can attract more of them to your boat to help get rid of the fishing spiders.
How do I keep spiders off my dock?
There’s no secret to it. If your dock is next to the water, you’ll have spiders. Use a combination of the techniques outlined on this page to keep them off.
A combination of essential oils, spider spray, dish soap, mothballs, plant removal, spider traps, sticky boards, and clutter cleanup can help.
But if you live somewhere that has a ton of wildlife in the water, you’ll have fishing spiders present trying to eat ‘em up.
What about spiders in my boathouse?
Spiders in the boathouse, lake hose or cottage are common because of the presence of water.
The water supplies the necessary growth medium for a variety of aquatic wildlife and dock spiders will feed on them by attaching their body to the shore and “fishing” for pests.
While you can’t do anything about the bugs in the water, you can prevent them from coming into your property annex.
Some tips to keep spiders out of your lake house, boathouse, cottage, or other buildings:
Keep all foliage surrounding the property clear.
You should cut and get rid of all plants you don’t need because they provide nesting sites for all sorts of bugs, which will cause the insect population around the area to rise. The more bugs you have, the more spiders will come.
If you need the vegetation, then keep them trimmed and tidy.
Remove water sources. Any standing or stagnant water sources should be removed.
Standing water attracts flies, slugs, snails, beetles, mosquitoes, and more. These are all food sources for spiders. Remove all water that’s backlogged and drain it.
Get rid of clutter. Spiders will need a place to hide in order to feel safe in the daytime when they’re resting.
Remove these objects and materials that they hide in so they have nowhere to go.
This may make them leave on their own or prevent them from establishing a nest in the first place.
Some of the most common places, objects, and surfaces spiders may hide in are:
- Outdoor furnishings
- Dense vegetation
- Storage crates
- Outhouses and sheds
- Garden equipment
- Trash bins, compost bins, recycling receptacles.
Sell, throw away, or get rid of clutter.
This will prevent spiders from taking shelter in your boathouse and stop other bugs from being attracted to the area and breeding.
What chemicals do spiders hate?
What spray kills spiders instantly?
Does tea tree oil keep spiders away?
How do I keep bugs off my boat?
Use a combination of the DIY technique listed throughout this guide.
Don’t just use one at a time, that takes far too long and is extremely inefficient to get rid of pests. Instead, combine the different techniques at the same time and see what works to get rid of the spiders.
For example, line your dock lines with spider sticky tape while you hang silver stringers on your boat. Keep the entire boat clean and wrap it with a cover when you’re not using it.
Set up mothball traps or hang dryer sheets around the outside. Spray peppermint oil in the cracks and crevices around the boat to keep spiders out.
It’s all about seeing what works then scaling it up. It’ll take patience and persistence to find out.
But if you’re able to control the flying insect population, you can greatly reduce the spider population also. Remember that fishing spiders float on the water to eat their prey.
Reducing the numbers of them on your actual boat can be done by exclusion methods, repelling them, and blocking entry.
But the insects in the water, which is rich full of their food, can’t really be eliminated.
You’re not going to kill everything in the vicinity of your docked boat.
So don’t worry about that. Just look after your boat because that’s all that you can control. This is the only way to keep spiders off your boat.
What will clean up spider poop and keep spiders off of the boat?
Spider poop can be cleaned up with a basic mixture of soap and water.
Use 2 tablespoons of dish soap per quart of water and scrub. If the feces have been just sitting there for an extended period, you can use a steam cleaner to remove the stains.
Cover your boat with spider netting to keep them out so they can’t poop on it and damage the paint.
There are also boat waxes you can use to protect the finish of your boat. Netting will also keep spiders off the boat if applied correctly.
Cover your boat when you don’t use it.
Here are some additional references you may find helpful for dock spiders:
- Dock Spiders – The Hull Truth
- Dock Spiders – Winnipeasaukke Forum
- Spiders on boat docks – Texas Fishing Forum
Did you clear your boat and dock of spiders?
You should now have everything you know to control, manage, and eradicate the dock spiders on your boat or property.
These spiders are considered to be beneficial insects, like most spiders, but when you have too many of them or need to deal with them on a daily basis, it can be quite a headache.
Were you able to rid the wharf spiders using these home remedies? Let me know in the comments below.
If you have any questions, please post a comment as well and I’ll get back to you.
If you found this guide helpful, please consider telling a friend who may get some use out of it!
Thanks for reading.
Currently an active researcher in the pest control industry for the past 8 years- with a focus on using natural and organic methods to eliminate pest problems.
I share handy DIY pest techniques I come across here to help out others (and possibly save them from a mental breakdown).
Fight nature with nature.