Giant house spiders (Eratigena atrica) eat insects and other small animals they catch in their funnel webs, such as flies, moths, beetles, woodlice and even other spiders. They are carnivores and do not eat vegetables, despite some myths. Here is what they eat, how they hunt and what it means if one turns up in your home.
What giant house spiders eat
- Flies, moths and crane flies
- Beetles, ants and woodlice
- Crickets and other small insects
- Other spiders and their own smaller relatives
- Occasionally small worms or caterpillars that wander into the web
Like all spiders, they cannot swallow solid food. They inject digestive fluid into their prey, then drink the dissolved contents.
How they hunt
Giant house spiders build a flat sheet web with a funnel-shaped retreat at one edge, often in corners, sheds, cellars, under sinks and behind furniture. The spider waits in the funnel, feels vibrations from prey crossing the web, then runs out very fast to grab it.
Do they eat plants?
Some spiders have been seen feeding on nectar or pollen, but giant house spiders are not plant eaters. Their diet is almost entirely made up of animal prey.
Why do I see more of them in autumn?
In late summer and autumn, adult males leave their webs to look for mates. This is when people most often find large spiders in baths, sinks and living rooms. Males are not hunting for food at this time and often do not eat much.
Are they dangerous?
Giant house spiders are not considered dangerous. They are shy and bites are rare. If bitten, wash the area and see a doctor if you have a reaction or are worried.
Keeping spiders out of your home
- Seal gaps around windows, doors, pipes and baseboards.
- Reduce clutter in cellars, garages and under beds.
- Vacuum webs and egg sacs.
- Reduce the insects they eat by fixing leaks and not leaving food out.
- To remove one, place a cup over it, slide card underneath and release it outside.
Frequently asked questions
How long can a giant house spider go without food?
Many spiders can survive weeks or even months without eating, especially in cool conditions.
Can I keep a giant house spider as a pet?
They are not usually kept as pets. If you try, you would need to offer appropriately sized live insects and a secure enclosure.
Is it the same as a daddy long legs?
No. Daddy long legs can refer to several different animals, including cellar spiders and crane flies. Giant house spiders are much bulkier.
Bottom Line
Giant house spiders are carnivores that eat flies, moths, beetles, woodlice and other small prey. They are harmless helpers for pest control, and seeing more in autumn is normal.
Related reading: What Do Pet Spiders Eat? and How Does a Spider Eat a Fly?
