Mike Oesterling states that the first sheddings are more water temperature controlled than by lunar phase. Once water temperatures are above about 59 °F (15 °C) crabs of all sizes begin to molt. Crabs begin shedding in April, generally in the shallower creeks and marshes, where sunny days can significantly elevate the shallow water temperature. These are also generally smaller-sized animals. The "first run" that people talk about is really the "doubler run" of mating females. There have been some years when this "run" did correspond to the May full moon, but over the past 8 to 10 years the "first run" in the lower York River and Mobjack Bay has occurred around May 15-19, regardless of moon phase. Additionally, this "run" occurs at different times in different sections of the Bay, again suggesting a water temperature impact.