The common bedbug, Cimex lectularius, relies exclusively on the blood of warm-blooded hosts for survival and reproduction. Understanding their feeding habits is central to managing and eliminating an infestation. These insects spend most of their time hidden in cracks and crevices, emerging only to feed, which makes their presence difficult to detect until the population has grown. Their frequency of feeding, meal duration, and ability to tolerate starvation contribute to their remarkable persistence as a pest.
The Typical Feeding Interval
Under average indoor conditions, an actively infesting adult bedbug typically seeks a blood meal once every five to ten days. This frequency sustains a reproducing population and allows females to generate eggs. Bedbugs do not need to feed every night; the majority of the population is usually dormant while digesting their last meal. This cycle dictates the timing of new bites a host may experience, though multiple bedbugs feeding independently can make bites seem like daily occurrences.
The Mechanics of a Blood Meal
Feeding almost exclusively occurs at night, generally between midnight and 5:00 a.m., when the host is in deep sleep and stationary. Bedbugs are attracted to the host’s warmth and exhaled carbon dioxide. Once a suitable location is found, the bedbug uses its specialized mouthparts to pierce the skin.
A single feeding session usually lasts between three and ten minutes, during which the insect becomes noticeably engorged with blood. Before feeding, the bedbug is flat and reddish-brown, but afterward, it appears swollen and darker. As the bedbug feeds, it injects saliva containing an anesthetic and an anticoagulant into the host’s skin. The anesthetic prevents the host from feeling the bite, and the anticoagulant keeps the blood flowing, causing visible bite marks days later.
Variables That Change Feeding Cycles
The feeding interval shifts significantly based on environmental and biological factors. Temperature is a major variable; warmer conditions accelerate the insect’s metabolism, requiring them to feed more frequently, sometimes every few days.
The bedbug’s life stage is another factor. Juvenile bedbugs, called nymphs, must feed at least once between each of their five molts to mature. If a nymph cannot obtain a blood meal, it cannot shed its exoskeleton, halting its development. If a host is absent for an extended period, the feeding cycle is dramatically extended into a survival state.
Starvation Tolerance and Survival
Bedbugs possess a remarkable ability to survive long periods without a blood meal. Adult bedbugs can survive without feeding for several months under normal room conditions. This resilience means vacating an infested property is not an effective control strategy.
Survival time is heavily influenced by temperature; colder conditions allow them to endure for much longer. When temperatures drop, bedbugs can enter a state of dormancy, significantly slowing their metabolic rate and conserving energy for up to a year. Younger nymphs have a lower starvation tolerance than adults, but their hardiness ensures infestations can persist long after a host has left.