zomervacht

Zomervacht, or the summer coat, is the lighter and shorter fur that many mammals develop during warmer months. The term is used in Dutch zoological literature to distinguish the seasonal pelage from the thicker winter coat. The change is part of the annual molt, driven by photoperiod and temperature, and may be complemented by changes in color as well as length.

During spring, animals shed the underfur and replace it with a thinner, less insulating coat. The zomervacht is typically shorter, sparser, and often of a warmer hue that blends with summer environments. Timing and extent vary by species and latitude, but the transition commonly occurs from late spring to early summer and lasts weeks.

Examples include many temperate-zone mammals such as the red fox (Vulpes vulpes), the European hare (Lepus europaeus), and various canids and mustelids. Domestic dogs and cats also undergo seasonal shedding, though the pattern may be irregular.

Functions of the zomervacht include improved heat dissipation, reduced overheating in warm weather, and camouflage that matches summer habitats. It is distinct from the primary molt that prepares animals for winter resilience, which generally produces a denser, longer coat.

In human contexts, discussions of zomervacht are common in natural history, wildlife management, and fur- or pet-care guides. See also pelage, molt, seasonal coat.