The head separates and a small sac inflates and pops the top off the pupa case. The sac then collapses, the fly's head reassembles itself, and the fly emerges from the case to float to the surface where it then begins its adult life cycle. Eventually adult flies return underwater to lay eggs or feed on algae. On calm days in the summer you can watch small, silvery teardrop shapes amble along the bottom of the lake in shallow water. At Mono Lake flies are food.
Most birds prefer dining on the flies.
Alkali flies provide more fat and protein than the brine shrimp. This is the principal food that Phalaropes use to grow new feathers and then migrate three thousand miles non-stop to South America. In the mid to late summer the Wilson's Phalarope can be seen spinning in shallow water, creating a miniature vortex that brings alkali fly larvae and pupae to the surface for easy pickings. You can also watch California Gulls and Brewer's Blackbirds run along the shoreline with beaks open filling themselves with adult alkali flies. The alkali fly was an important source of food for the Kutzadika'a people during the summer months.