The common household term “daddy long legs” refers to two distinct types of arachnids: harvestmen and cellar spiders. Many wonder if these creatures can help manage bed bug infestations. Understanding their biology and habits is important for addressing this common misconception.
Daddy Long Legs: Fact vs. Fiction on Bed Bugs
The belief that “daddy long legs” effectively eat bed bugs is a widespread misconception. Neither harvestmen nor cellar spiders are reliable predators of bed bugs due to their differing biology, hunting strategies, and preferred habitats.
Harvestmen, not true spiders, belong to the order Opiliones. They have a single, fused body segment, do not produce silk or venom, and ingest solid food particles.
Cellar spiders, true spiders from the family Pholcidae, have two distinct body segments and spin loose, irregular webs to capture prey.
Bed bugs (Cimex lectularius) are small, flat, nocturnal insects that hide in tight crevices like mattress seams and bed frames, emerging to feed on human blood.
Harvestmen typically inhabit damp, dark places like leaf litter or basements, scavenging or ambushing small invertebrates. Cellar spiders usually build webs in undisturbed indoor corners, catching flying insects. The significant difference in habitat means encounters between “daddy long legs” and bed bugs are infrequent and incidental, insufficient to control an established bed bug population.
The True Diet of Daddy Long Legs
Understanding the actual diets of “daddy long legs” clarifies their ecological roles. Harvestmen are primarily omnivores and scavengers, consuming decaying plant and animal matter, fungi, and carrion. They also opportunistically prey on small, soft-bodied invertebrates like aphids, mites, and earthworms.
Cellar spiders, as web-building predators, primarily feed on small flying insects such as mosquitoes, flies, and moths that become entangled in their webs. They also prey on other spiders, including larger species like house spiders and even black widows. While this helps control various household pests, bed bugs generally fall outside their typical prey range due to their hiding habits.
Reliable Bed Bug Management
Since “daddy long legs” do not provide effective bed bug control, implementing proven management strategies is important. Identifying bed bugs is the first step, often indicated by dark specks of excrement, shed skin casings, or rusty bloodstains on mattresses and bedding. Bed bugs are tiny, around 5 millimeters long, and adept at hiding in narrow spaces.
Effective management often involves a combination of non-chemical and chemical methods. Non-chemical approaches include:
- Washing and drying infested items in hot water (at least 120-140°F or 49-60°C) for 30 minutes.
- Steam cleaning mattresses and furniture at high temperatures (150-170°F or 65-75°C).
- Using professional heat treatments to raise room temperatures to over 113°F (45°C).
- Freezing infested items at 0°F (-19°C) for at least four days.
Thorough cleaning, such as frequent vacuuming of crevices and reducing clutter, removes some bed bugs and reduces hiding spots. Encasing mattresses and box springs with bed bug-proof covers helps trap existing bugs and prevents new infestations. Prevention is also important, involving careful inspection of secondhand furniture and luggage before bringing them home, and sealing cracks and crevices in walls. For persistent or widespread infestations, professional pest control is often recommended for comprehensive eradication.