Alkali Nomia

The alkali bee is about two-thirds the size of a honeybee with black and metallic banding on the abdomen. Females have, but infrequently use, stingers and the males have white faces. Males and females in the northern part of the range are larger than their counterparts to the south. This is theorized to allow larval bees to survive for longer without food and may also be related to a slightly longer day in the summer, allowing for increased brood provisioning.

The alkali bee lives in arid climates, primarily desert basins in the western United States from central Washington to southern California and east to western Colorado. They prefer to nest in moist, silty soils that have good drainage, a salty surface, and don't have vegetative groundcover. The hydrology of the soils appears to be the controlling factor for where nests are made. As soil makeup affects water retention and capillary action, soils with some clay and sand but mostly silt are preferred.

While solitary, alkali bees frequently nest in high densities. Females lay 1 to 2 eggs a day, and spend most of the day building the cell for the egg. Immediately after emergence a female begins to excavate the main burrow which usually entails digging for about 12 hours. The dirt is removed and using the mandibles and foretarsi, formed into pellets which are then deposited around the entrance to the burrow. The burrows are usually about 15–20 cm in depth, but in laboratory conditions with looser soil, much deeper burrows have been created. In addition to the main vertical burrow, smaller passageways are dug horizontally. From these shorter tunnels, small vertical holes called cells are created for oviposition. Cell creation usually begins the night after the main burrow is excavated. First, the "mine burrow" is dug and then a soil lining applied to the sides which reduces the size of the cell. Lastly a clear, lipid-rich secretion from the Dufour's gland (in the abdomen) is applied to the interior of the cell to waterproof it. After the cell is constructed, the female bee begins the process of provisioning. She brings back pollen and mixes it with nectar to form a ball which is then placed in the bottom of the cell. Any debris that makes its way into the cell during this period is meticulously removed. Once the pollen ball is completed, oviposition occurs. …