When are bedbugs active? - briefly
Bedbugs are mainly nocturnal, leaving their harborage to feed soon after a person goes to sleep, usually during the night hours. They can become active during daylight if their hiding places are disrupted or if a host is readily available.
When are bedbugs active? - in detail
Bedbugs (Cimex species) are primarily nocturnal feeders. Adult insects emerge from hiding to locate a host shortly after the host settles into a resting position, usually within 5–10 minutes of darkness. Their feeding window extends through the night, with peak activity occurring during the early to mid‑hours of sleep (approximately 10 p.m. to 3 a.m.). As dawn approaches, most individuals retreat to harborages and remain concealed until the next night.
Environmental temperature strongly influences the length of the active period. At ambient temperatures of 24–27 °C (75–80 °F), development accelerates and night‑time activity may begin earlier and persist longer. Below 15 °C (59 °F), metabolic rates drop, feeding intervals lengthen, and insects may postpone meals for several days. Conversely, temperatures above 30 °C (86 °F) can increase feeding frequency, sometimes prompting multiple meals within a single night.
Life‑stage differences affect movement patterns. Nymphs, which must feed after each molt, exhibit more frequent host‑seeking behavior than adults, especially when starved. Eggs are immobile and remain in protected crevices until hatching, after which the newly emerged first‑instar nymph joins the nightly feeding cycle.
Key factors governing nightly activity:
- Light level: Darkness triggers host‑seeking; exposure to light suppresses movement.
- Host presence: Carbon dioxide and heat cues from a resting host stimulate emergence.
- Temperature: Optimal range (24–27 °C) maximizes feeding frequency; lower temperatures delay activity.
- Starvation: Extended periods without a blood meal shorten the interval before emergence.
Understanding these patterns helps in timing inspections and treatments, as detection is most reliable when insects are concealed in their harborages during daylight hours.