Cellophane bees are one of the first bees to emerge in the spring, sometime between March and May. These solitary bees nest underground, often in close proximity to one another, with each female digging her own burrow off of which she creates several individual brood cells. Each cell is lined with a cellophane-like secretion which is applied with her short brush-like tongue to the walls of the cell. She then fills the lower portion of the cellophane sac with pollen, nectar and some glandular material, lays an egg and seals the cell with more cellophane-like substance and a bit of sand for a cap. The female then goes on to repeat the process and digs another cell.
The egg hatches and the larva grows throughout the summer, feeding on the supply of nectar and pollen contained within the cell. The larva metamorphoses in the fall and overwinters as a pupa inside the natal cell, emerging as an adult on a warm, sunny spring day.
Males, which emerge before the females, can currently be seen patrolling the area where last year’s burrows were constructed, flying just an inch or two above the ground, searching for emerging females digging themselves out of the ground. When a female is spotted, she is often bombarded by one or more males, creating quite the cluster of bees. One male prevails, mating takes place, and the cycle continues.
Ninety percent of bees are solitary – the fertile females create their own cells and feed their own young, with no help from a colony of worker bees. They often nest underground, rarely sting and are excellent pollinators, even though they don’t store honey. Colletes inaequalis, a type of Plasterer Bee also known as the “Polyester Bee,” and “Unequal Cellophane Bee,” is a solitary bee. It derives its common names from the practice of lining its underground nest cells with a secretion that, when it dries, forms a smooth, cellophane/polyester-like lining. This cell holds one egg suspended above a collection of pollen and nectar on which the larva will feed. The Unequal Cellophane Bee is crepuscular, which can be deduced by the large size of its eyes. It is one of the earliest species to become active in the spring, sometime between March and May, when adults bees emerge from underground chambers off a vertical tunnel dug by their mother last spring. (Why it is called an “Unequal” Cellophane Bee I have not been able to determine.)