“Daddy long legs” is a common term that refers to two distinct types of arthropods: harvestmen, which belong to the order Opiliones, and cellar spiders, members of the family Pholcidae. While both possess notably long, slender legs, they differ significantly in their biological characteristics. Harvestmen have a fused body region, two eyes, and do not produce venom or silk. In contrast, cellar spiders are true spiders, featuring two body segments, multiple eyes, and the ability to spin webs and produce venom. These adaptable creatures frequently inhabit human dwellings and gardens.
Other Arachnids
Other arachnids are prominent predators of daddy long legs. Many spider species, particularly larger web-building spiders or active hunters, will prey upon them. Cellar spiders themselves are known to be cannibalistic and will consume other spiders, including larger house spiders, wolf spiders, and even venomous species like redback spiders. They often invade the webs of other spiders, mimicking the vibrations of trapped prey to lure the unsuspecting host, then capturing and consuming it. Beyond cellar spiders, various hunting spiders actively pursue daddy long legs. The Portia genus of jumping spiders, for instance, are known for their sophisticated hunting strategies, which include mimicking leaf litter or creating specific web vibrations to deceive and capture other spiders. Scorpions also pose a threat to harvestmen in regions where their habitats overlap.
Insects and Myriapods
Insects and myriapods also contribute to the predation of daddy long legs. Predatory insects like assassin bugs are known to target harvestmen, ambushing them in their habitats. Wasps can also be predators of both harvestmen and cellar spiders, often encountering them in and around human structures. Centipedes are effective predators of both harvestmen and cellar spiders, using their multiple legs and venom to overpower them in darker, moist environments. Larger generalist insect predators, such as praying mantises, may also opportunistically consume daddy long legs if encountered, given their broad insectivorous diets.
Birds and Small Animals
A variety of birds and small animals prey on daddy long legs. Insectivorous birds, including wrens, sparrows, blackbirds, robins, blue tits, and bluebirds, frequently consume spiders as part of their diet. They forage in gardens and around structures where daddy long legs are common. Small terrestrial animals like lizards and frogs are also documented predators. Lizards are known to eat daddy long legs, with specific observations of geckos preying on cellar spiders. Frogs, being opportunistic carnivores, will consume various insects and spiders that fit into their mouths. Shrews, small mammals with high metabolisms, actively hunt arthropods such as spiders, millipedes, and centipedes, locating them through acute hearing and smell. Additionally, omnivorous rodents like mice and rats may opportunistically consume spiders, particularly when other food sources are scarce.