What strong behavioral trait is noted for the males of many *Anthidium* species in the field?

Being highly territorial, aggressively defending nesting sites or favored flower patches

While female *Anthidium* bees focus their unique energy on nest construction by carding wool, the males of many species within this genus exhibit distinct and observable aggressive territoriality. This behavior is often seen when males vigorously patrol and defend specific areas, which may include favored patches of flowers essential for nectar acquisition or, more critically, established or potential nesting locations. They will actively confront and chase away other insects, including other male Wool Carder Bees, that enter their defended perimeter. This strong patrolling and defense behavior serves as an important fieldwork indicator for identifying the presence of the *Anthidium* genus.