Calabaza plants are monoecious and are pollinated by insects like honeybees and bumblebees. Flowers attract varied pollinators including bumblebees, carpenter bees, Bombyliidae, and hummingbirds. Similar behavior is observed in other Hymenoptera including stingless bees, wasps, bumblebees and ants. Many pollinators and predatory insects such as lady beetles, bumblebees, and hoverflies are relatively unaffected. The flowers support pollinators, including of special value to Native bees, honeybees, and bumblebees. Invertebrate populations (including bumblebees, butterflies, grasshoppers, dragonflies, and spiders) significantly decreased. The flower is pollinated by bumblebees and other bees. They are pollinated by insects such as bumblebees and carpenter bees, and are self-sterile. Many others rear their young in burrows and small colonies (e.g., bumblebees and stingless bees). The larvae were "Apocephalus borealis", a parasitoid fly known to prey on bumblebees and wasps. In New Zealand, the pollinators of this plant are bees, bumblebees, and medium-sized birds. However, many other species of bees, including bumblebees, such as "Bombus terrestris", are monandrous. However, good pollinators are said to be bumblebees and hairy flies of the genus "Bombylius". The flowers are visited by various insects including Noctuidae, Sphingidae, bumblebees, and hoverflies. Female Bee Moths (Aphomia sociella) prefer to lay their eggs in the nests of bumblebees.