Lake Arenal has an area of over 75 sq. km. and is populated primarily by two different types of fish, the Machaca and Rainbow Bass. The Machaca are flashy acrobatic fish that can reach 9 pounds within the lake, and perhaps 15 pounds in northern and coastal rivers. The Rainbow Bass is a very challenging game fish, which earned its name because of the subtle gradations of colour and the fact that they are fished just as you would for largemouth bass. In Spanish its name is "Guapote", which means "the most handsome". The Rainbow Bass is found only in fresh water rivers and lakes in Costa Rica, Nicaragua and Honduras. In Lake Arenal, the Guapote weighs up to 12 pounds and is taken with bass lures, deep runners and jigs. It is shaded in pastel hues, has a fearsome set of teeth, and feathered dorsal and caudal fins.
Escapees from a breeding program added a few Tilapia to the population and there are rumors of a surreptitious planting of largemouth bass but no confirmed reports of any ever being caught. Local fishing experts believe vehemently that the big fish should be released and keep only the smaller fish for immediate consumption, which is not a bad idea considering the unanimous vote of anyone who's ever set fork to a rainbow bass that's it's the best eating of any fish in the world.
