Sneaky thieves
While most bees collect pollen on their legs, abdomen, or in an internal crop, some bees don't collect pollen at all! These bees are called "cuckoo bees" and they are opportunisitic bees that rely on other bees. Rather than building and provisioning their own nests, they sneak into the nests of other bees and lay their eggs in the cells prepared by the host bee. The cuckoo bee egg normally hatches first and kills the egg/larva of the host bee.
While this type of behavior may seem bad, the good news is that if you see cuckoo bees, it is an indicator that there are healthy popultions of native bees, enabling the cuckoo bees to thrive as well. Most bee families have cuckoo bees.
While this type of behavior may seem bad, the good news is that if you see cuckoo bees, it is an indicator that there are healthy popultions of native bees, enabling the cuckoo bees to thrive as well. Most bee families have cuckoo bees.

Coelioxys
Photo by Karla Salp

Sphechodes
Photo by Aidan Hersh

Brachymelecta
Photo by Aidan Hersh

Triepeolus
Photo by Aidan Hersh

Nomada
Photo by Lisa Hill

Bombus
Photo by T. Abe Lloyd

Coelioxys
Photo by Mike Davidson

Epeolus
Photo by Lisa Robinson