Spiders follow their food supply, which means if your dock has lights that draw insects at night, standing water nearby, and sheltered crevices for web-building, it's prime spider habitat. You need to reduce what is attracting them by managing lighting, clearing webs regularly, and reducing insect activity around the dock.
Docks collect spiders for the same reason they collect everything else. Around docks, there is water, light, and structure. That is enough to draw insects, which in turn draw in spiders.
Lighting is the biggest factor among them. Dock lights, pier lights, and even ambient light from a nearby boathouse attract moths, mayflies, midges, and other flying insects after dark. Spiders build webs near these lights because the food comes to them. Switching to yellow or amber bulbs (which attract fewer insects than white or blue-white light), though it sounds like a very small detail, can greatly reduce the presence of insects and the spiders that follow them.
Removing webs is tedious. It also works. Knocking down webs regularly with a broom or pressure washer disrupts the spiders' feeding cycle. Most dock spiders will rebuild, but consistent removal makes the location less productive for them and encourages them to move elsewhere. Be sure to look at corners, railing junctions, under handrails, and the underside of dock boards—basically, anywhere that is protected from the rain.
Moisture around and under the dock supports the insects that spiders feed on. If there are areas near the dock where standing water collects, like buckets and coiled hoses or unused planters, removing them reduces the insect population in the immediate area. (And as a bonus: it helps with mosquitoes.)
Sealing gaps in dock boxes, storage compartments, and boathouse walls also helps. Spiders that aren’t actively building webs seek out dark, undisturbed spaces during the day. The fewer of those spaces that are available to them, the fewer spiders you will see.
If spiders or other pests are a problem around your North Shore waterfront property, Mosquito Squad of North Shore can help. Mosquito Squad treats the areas around your home and outdoor structures where pests harbor, reducing populations with regular technician visits throughout the season.
