113051.FG.0822.Slime.Palmyra.RL–Palmyra Atoll– A researcher counts fish swimming around a coral reef at Palmyra Atoll in the central Pacific. Coral reefs are threatened by multiple threats including removal of fish that keep algae in check and pollution that feeds algae growth. Scientists say such reefs also face a threat from changing chemistry of the seas. As the oceans become more acidic by absorbing CO2, the coral polyps will lose the calcium carbonates, or basic chemical building blocks they extract from seawater to build their exo-skeltons.