Beekeepers will describe a colony 'throwing a cast', which is a term used to describe the emergence of an after-swarm. Colonies preparing to swarm will raise many new queens, possibly several dozen, which will emerge at different times. Once the larvae have been sealed in their cell and the worker bees can no longer care for them the first, or 'prime', swarm will leave the nest with their queen. In subsequent days pupating worker bees will continue to emerge, swelling the population once more, and the developing queens will begin to 'hatch'. If the population is sufficiently great these new unfertilized queens will also leave, with a proportion of the remaining bees, as 'casts'. The process will continue until the population is too small to support further division, at which point the remaining un-hatched queen pupae will be destroyed by one of the queens or the workers to leave a single, new, unmated queen.