How long can bedbug larvae survive without blood? - briefly
Bed‑bug nymphs can endure starvation for roughly three to six weeks, with survival extending to about 40 days under cool, humid conditions. Mortality increases sharply after this period.
How long can bedbug larvae survive without blood? - in detail
Bed bug nymphs can persist for several weeks without a blood meal, but the exact period varies with developmental stage, temperature, and humidity. First‑instar nymphs, which have just moulted from eggs, possess the smallest energy reserves and typically survive 3–5 days at 22 °C (72 °F) if no host is available. As they progress to later instars, stored nutrients increase, extending starvation tolerance.
- Second‑instar: 7–10 days at moderate temperatures.
- Third‑instar: 10–14 days under the same conditions.
- Fourth‑instar: 14–21 days, with some individuals reaching three weeks.
- Fifth‑instar (final nymphal stage): 21–30 days, occasionally longer in cooler environments.
Temperature exerts a strong influence. At lower temperatures (15 °C/59 °F), metabolic demand drops, allowing nymphs to survive up to 1.5 times longer than at 22 °C. Conversely, at higher temperatures (30 °C/86 °F), starvation periods shorten by roughly 30 %. Relative humidity also matters; dry conditions accelerate desiccation, reducing survival by 10–20 % compared with humid settings (≥70 % RH).
Physiologically, nymphs rely on lipid reserves accumulated during previous blood meals. Each moult depletes a portion of these stores, and failure to ingest blood before the next moult results in developmental arrest and eventual death. In laboratory studies, nymphs that missed a single blood meal at the fifth instar still completed development if provided a meal within 10 days; beyond that window, mortality approached 100 %.
In summary, bed bug nymphs exhibit a staged starvation tolerance ranging from a few days for the youngest instar to roughly one month for the oldest, with environmental temperature and humidity modulating these limits.