Trapnests

Trapnests, also written trap nests, are artificial nesting cavities used primarily in entomology to study and rear cavity-nesting bees, wasps, and related insects. They simulate natural nesting sites and enable standardized data collection on species diversity, phenology, and life history.

Construction and deployment: Trapnests come in various forms, including wooden blocks drilled with multiple holes, cardboard or paper tubes placed in protective casings, or bundles of hollow stems. Hole diameters typically range from 2 to 10 millimeters to target different species. The cavities are left open to natural conditions while the outer casings provide some protection from weather and predators. They are mounted on poles, fences, or within hedgerows and are often grouped to allow comparison among microhabitats. They are usually inspected at set intervals to remove emerged adults and to collect brood cells for rearing or identification.

Applications and data: Researchers use trapnests to inventory pollinators, study nesting preferences, monitor seasonal emergence, and assess parasitism and interspecific interactions. Data from trapnests support conservation planning for solitary bees and help quantify habitat quality.

Considerations: The use of trapnests can influence local insect populations if used intensively or concentrated in small areas. Proper design, spacing, and ethical handling are recommended to minimize harm and avoid skewing results. They should be maintained and replaced periodically.

History and terminology: The method dates to early entomological surveys and has since become a standard tool in ecological studies of cavity-nesting Hymenoptera, though the term trap nest is preferred in modern usage to describe both the cavities and their ecological role.