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Thousands of mussels were cooked alive on Point Reyes during three days of extreme heat that coincided with daytime low tides. Scientists say that unusual overlap will become increasingly common.   Courtesy of the National Park Service

The three-day heat wave in early June cooked tens of thousands of mussels in their shells in the intertidal zones along the Marin and Sonoma coasts. 

Preliminary data from the Bodega Marine Laboratory, where one researcher made the initial finding, shows an average 30 percent loss throughout the Bodega Marine Reserve and up to 70 percent losses in some areas. 

The dense heat coincided with daytime low tides and topped average temperatures for the time…