nestbuilding

Nestbuilding refers to the construction or arrangement of materials by animals to form a structure that provides protection and an environment for reproduction and rearing of offspring, as well as shelter and food storage. Although most widely associated with birds, nestbuilding occurs in many taxa, including several mammals, insects, reptiles, and some fish. The activity is influenced by environmental conditions, material availability, predation risk, and the species' reproductive strategy.

Birds build a wide range of nests, from cup-shaped ground nests to elaborate suspended structures. Materials include twigs, leaves, grasses, mud, feathers, and saliva; certain species weave or stitch materials into woven or stitched nests. Notable examples include weaverbirds' intricate suspended nests, wrens' cup nests, and orioles' paper-like nests. Insects such as bees, wasps, termites construct waxen, paper, mud, or burrow nests; social insects may use large communal nests that house thousands of individuals.

Nests serve multiple functions: incubation of eggs, protection from weather and predators, and a place for offspring to develop; they may also provide storage for food or shelter for dependent young. The microclimate within a nest—temperature, humidity, and draft—greatly affects success and may influence parental care patterns. Nest location is often strategic, balancing concealment and accessibility to foraging grounds.

Evolution and ecology: nest design reflects adaptive trade-offs between construction effort, material availability, predator pressure, and climate. Colonial species may build communal nests or occupy shared cavities; some birds reuse nests in successive seasons. Nest-building behavior shows plasticity in response to environmental change, and fossil and comparative studies reveal convergent patterns across distant lineages.

In human contexts, nest-building is studied as a model of animal behavior and is used in conservation to assess habitat quality, or to understand the impact of changing landscapes on reproductive success.