The rainbow bass is the prize game fish found in the freshwater lakes and rivers in Costa Rica. Known locally as “guapote”, which in Spanish means ‘handsome,’ they are also the best tasting fresh water fish caught here. They are aggressive carnivores that can be fiercely territorial, and when hooked they can take off like grey hounds and are strong enough to snap weak lines or poorly tied knots. Guapote are naturally found in the rivers throughout Costa Rica but have really found a real home for themselves on Lake Arenal. Costa Rica’s largest lake, Lake Arenal was formed in 1978 when the area was flooded to create more affordable hydroelectric power for the country. The IGFA world record guapote was caught in Costa Rica in 1991 (12 lbs 9 oz) but was then re-broke shortly after by an angler in Nicaragua.
Much like the peacock bass in Panama, rainbow bass aren’t actually bass – they too belong to the cichlid family. They get the ‘rainbow’ part of their name due to their beautiful colorings. Mature males will display red and green on their heads before turning to a golden-yellow body that is speckled with blue, black, and purple dots and dark vertical bars. Mature adults can also feature a very pronounced forehead bump. Their fins typically showcase a bluish-green color, which when all put together makes it easy to how it earned its name. Armed with a mouth full of imposing teeth, guapote earned their ‘bass’ moniker due to the way they are fished.
WHAT THEY EAT : Rainbow bass are top predators in most rivers and lakes in Costa Rica. With their size, speed, and nasty set of teeth they feed primarily on smaller fish but can also eat frogs and insects. They seem to be most aggressive right before and after spawning but can be rather lazy during nesting.
WHERE TO FIND THEM: Rainbow bass are found in fresh water rivers all over Costa Rica, but certainly the main spot to fish for them is Lake Arenal. They prefer warm slow moving water that has plenty of structure, and at 33 sq miles Costa Rica’s largest lake has plenty of both. In the early morning and evening you can catch guapote with crank baits and spinner baits in shallower water near tree stumps, underwater shelves, rocks, and grassy areas but once the hot tropical sun is overhead they typically move to deeper and cooler water. Guapote will burrow ‘nests’ into the mud banks around the lake just under the surface of the water, so when water levels drop during the dry season these can be seen and guapote are often found close by. The biggest guapote are often taken trolling deep diving lures through the coolest spots in the lake.