Lake Atitlan, described by some as the most beautiful lake in the world, lies at an elevation of 5,100 feet in the highlands west of Guatemala City. It occupies a large volcanic crater with a depth of 1,000 feet or more and a surface area of 79 square miles.
The water of Lake Atitlan is clear, visibility being as great as 39 feet, and the temperature remains constant year-round at 70-72° F. Two small rivers, rainfall, and underground sources supply the lake with water. It does not have a visible outlet, but drains from the bottom. Because of the alternating rainy and dry seasons, the water level fluctuates by about three feet each year.
Steep slopes, including three volcanic peaks, surround the lake on all sides. Large growths of reeds and cattails grow along about 15 miles of the shoreline. These tend to filter the runoff from the surrounding slopes and provide wildlife habitat for many species.
Wildlife abounds in, on, and around the lake. Aquatic species include 18 kinds of small fish, various amphibians such as frogs and salamanders, crabs, crayfish, and numerous small invertebrates such as insects.
Bird species found in the area include herons, which are large, long-legged wading birds with long necks. They typically stand motionless in shallow water, waiting to spear frogs and fish with their long beaks. They make nests of sticks in bushes and trees.
Ducks of various kinds can be found. A prominent example is the ruddy duck, so named because of its bronze-colored body. Its diet is about one-fourth aquatic animals and three-fourths plants. It feeds on the surface or by diving, often at night. The nest of up to 20 eggs floats among reeds and rushes. This duck flies well, but needs a long run before take-off.
Gallinules and coots are chicken-like birds found wading in shallow-water areas. Their long toes allow a distribution of their weight as they walk across lily pads to feed. They also feed on land, as well as by swimming and diving. Food includes frogs, shellfish, insects, and plants. They are not good flyers. Their nests are either floating or out of water on a clump of grass.
Giant grebes are native birds thought to live only on this lake. Rather than webbed feet, they have long, lobed toes. Their legs are placed far back on their bodies, making them almost helpless on land. Wings are small compared to their body size, so flight is impossible. These birds are excellent divers, however. They make a floating nest for 2-5 eggs in shallow water among reeds. They feed on tul (an aquatic plant), fish, and invertebrates.
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