Daddy long leg spiders (cellar spiders) eat flies, mosquitoes, moths, ants, and other small insects caught in their loose webs. They also hunt other spiders, including house spiders and, in some parts of the world, redbacks. They do not eat plants.
How Cellar Spiders Hunt
A cellar spider hangs upside down in a tangled web in a corner, cellar, garage, or ceiling. When an insect lands in the web, the spider throws a few strands of silk over it from a distance with its long legs, then wraps it. It bites last, which keeps it away from prey that fights back. When another spider enters the web, the cellar spider shakes the web or approaches carefully and wraps its target in silk.
What They Eat
- Flies, fruit flies, and mosquitoes: the everyday catch.
- Moths, ants, and small beetles: caught when they stumble into the web.
- Other spiders: including house spiders and widow spiders.
Which Animals Are Called Daddy Long Legs?
People use the name for three animals. Cellar spiders are true spiders. Harvestmen are a separate arachnid group and are not spiders: they eat small insects, dead insects, fungi, and plant matter, and they do not make silk. Crane flies are flying insects. This post covers cellar spiders. See our guide to what granddaddy long legs eat for the harvestman side.
Are Cellar Spiders Venomous or Dangerous?
All spiders have venom, but cellar spiders are not a danger to people. The idea that they are the world’s most venomous spiders but have fangs too short to bite is a myth. Cellar spider bites on humans are rare, and there is no evidence they cause serious harm.
Are They Good to Have?
Yes. A few cellar spiders in a basement keep flies, mosquitoes, and other spiders under control. If their webs bother you, remove the webs with a vacuum or broom. The spiders usually come back in time if the insects are still there.
Related: what daddy long legs eat and what tiny house spiders eat.
Bottom Line
Daddy long leg spiders eat flies, mosquitoes, moths, ants, and other spiders. They are harmless to people, and they are useful house guests.
