How does a spider mite spend the winter? - briefly
Spider mites overwinter mainly as dormant eggs or adult females that occupy protected microhabitats such as leaf litter, bark crevices, or greenhouse structures, entering «diapause» to survive low temperatures. When spring temperatures increase, development resumes and the mites colonize host plants.
How does a spider mite spend the winter? - in detail
Spider mites survive the cold season primarily through diapause, a hormonally regulated suspension of development that reduces metabolic demand. During this period, most individuals remain in the egg stage, which tolerates low temperatures better than active larvae or adults. Eggs are deposited on the underside of leaves, in leaf folds, or within protected crevices of plant stems, where microclimatic conditions remain relatively stable.
Key overwintering strategies include:
- Selection of insulated microhabitats such as leaf litter, bark cracks, or greenhouse structures that retain heat and moisture.
- Production of a waxy coating on eggs that limits desiccation, enhancing survival when ambient humidity drops.
- Reduction of feeding activity; dormant individuals cease plant consumption, conserving energy reserves.
- Synchronization of life‑cycle timing with environmental cues; photoperiod shortening and temperature decline trigger diapause initiation.
Temperature thresholds define survival limits. Most spider mite species tolerate temperatures down to 5 °C, but prolonged exposure below this point sharply decreases viability. Relative humidity above 60 % further improves overwintering success by preventing egg desiccation.
In temperate regions, populations often persist in protected horticultural settings, such as glasshouses, where artificial heating maintains temperatures above the critical limit. In outdoor crops, residual leaf debris and hedgerows serve as refuges, allowing a fraction of the colony to re‑emerge in spring.
When spring arrives, rising temperatures and increased daylight length terminate diapause. Eggs hatch, and the surviving cohort rapidly expands, exploiting the renewed availability of host foliage. The swift population growth is facilitated by the high reproductive capacity of spider mites, with each female capable of laying dozens of eggs over a short period.
Overall, winter survival hinges on developmental arrest, selection of sheltered sites, and physiological adaptations that mitigate cold‑induced stress. These mechanisms ensure the continuity of spider mite populations across seasonal cycles.