Do bedbugs prefer light or darkness? - briefly
«Bedbugs» are negatively phototactic, seeking dark, concealed environments; exposure to light suppresses their activity. They emerge during nighttime to locate and feed on hosts.
Do bedbugs prefer light or darkness? - in detail
Bedbugs are primarily nocturnal insects that seek shelter in concealed, dimly lit locations such as mattress seams, wall cracks, and furniture upholstery. Their activity peaks during the night when host cues—heat, carbon‑dioxide, and scent—are strongest, while ambient illumination is minimal.
Laboratory investigations consistently demonstrate negative phototaxis. When placed in arenas with contrasting light and dark zones, individuals migrate toward the shaded side, often within minutes. This behavior aligns with observations in field settings, where infestations concentrate in areas shielded from direct sunlight.
Feeding occurs at night; bedbugs locate hosts through thermal and olfactory signals rather than visual stimuli. The brief exposure to light during host contact does not alter their preference for darkness, as the insects quickly retreat to protected microhabitats after a blood meal.
Occasional reports describe slight attraction to low‑intensity light in early nymphal stages, yet these instances represent minor deviations. Overall, the species exhibits a strong inclination toward low‑light environments throughout its lifecycle.
Practical consequences include:
- Monitoring devices that rely on bright illumination are generally ineffective.
- Reducing clutter and sealing cracks diminish dark refuges, limiting population growth.
- Inspection protocols prioritize examination of concealed, shadowed areas.
Scientific consensus affirms that bedbugs favor darkness over illumination, a trait that influences both their ecology and control strategies. « Bedbugs demonstrate a marked avoidance of light, seeking darkness for shelter and feeding activities », as summarized in recent entomological reviews.