Spongy (Gypsy) Moth Life Cycle
The adult female spongy (gypsy) moth very different from the male. She is larger, white in color, and does not fly (the exception is the Asian strain). She emerges from the pupa in mid to late summer and is generally mated in a matter of minutes. She then crawls to good spot to lay the eggs (if she is not already there) and begins depositing the egg mass. The size of the egg mass varies depending upon size and nutrition of the female but the average number of eggs in egg masses in Midland County, Mi is 524.
After completing the egg mass, the female remains in the area and if undisturbed, she will die in a day or two. Birds will sometimes feed on female spongy (gypsy) moths but they do not seem to be a prime target for most birds. The white moths are often found lying dead at the base of the tree they emerged on.