Climate change is also making ocean waters more acidic, potentially harming shellfish like oysters.

MARSHALL, CALIFORNIA – AUGUST 20: Workers at Tomales Bay Oyster Co. sort freshly harvested oysters on August 20, 2019 in Marshall, California. According to a study by UC Davis, estuarine and bayland habitats are being directly affected by climate change and is interfering with the growth of oysters in the Tomales Bay. Freshwater creeks brought on by heavy rains are flowing into the bay are causing acidic and oxygen-deprived water to rise to the surface. This is impacting the growth and survival of oysters that are being farmed. The Tomales Bay Oyster Co. reported a 70 percent loss in some of their harvest areas that were affected by creek runoff from heavy winter rains. Warm summers have also had significant changes in water temperature on the bay with some areas rising 10 degrees over normal. (Photo by Justin Sullivan/Getty Images)