Remsen, J.V. 1974 Great Blue Heron Ardea herodias Jan 5 Berkeley Aquatic Park, Alameda Co., Calif : 1 Mar 3 Why are some herons white and others dark? Could it be due to different visibilities to fish from underneath the water. White birds should be very difficult to see in bright, sunny areas, whereas it would be better to be a dark object in dark water. Great Egret, Snowy Egret, Wood Stork, and Cattle Egret definitely seem to feed in unshaded water, whereas Green Heron, Little Blue Heron, and Louisiana Heron feed in more shaded areas. Why does the Great Blue Heron become the "Great White Heron" in S. Florida? Great White Herons are mainly salt water feeders, and salt water is seldom shaded (but Great Blues probably feed as much in unshaded as shaded water throughout the rest of their range). The test would come be to see if if there are habitat differences in light vs. dark Reddish Egrets or qd. vs. imm. Little Blue Herons Dec. 21 Boulder area, Boulder Co., Colo: 4