The South San Francisco Bay salt evaporation ponds, which are often visible from planes flying in and out of San Francisco Airport. Salt ponds with different salinity levels are inhabited by different organisms that give them different colours. Algae colour low salinity ponds green, while different algae color high salinity ponds red. Bacteria and shrimp also shift the colours.

Hidden Ecologies is blog describes work from the San Francisco Exploratorium that explores and visualizes the transitional landscapes surounding San Francisco Bay at different scales. Architect Cris Benton has made a collage of his photos from high and low elevations of Salt Pond Colors: