Granito de Oro, Panama
Overnight we sailed from Costa Rican to Panamanian waters, and by mid-morning we were anchored off Isla Coiba. Birders went ashore on a nearby island and had wonderful luck; they found a lek of lance-tailed mannikins. In this species of forest bird, two or more male birds clear a small area on the forest floor, then vocalize, dance together, and make loud snapping sounds with their wings. It is thought that with more than one male, there is a greater chance of attracting the attentions of any available females for mating.
The underwater sights were even more exciting. While we were snorkeling and SCUBA diving at the tiny islet called Granito de Oro, we found fish engaged in many different and interesting behaviors. A large school of fish called spottail grunts maneuvered tightly together as a predatory fish called a blue crevalle jack swam around and through the school in search of a meal. No grunts left the protection of the school, and the predator did not get a meal - at least while we watched. Right on the bottom many sergeant majors were spawning. Unlike the grunts, these fish were being very territorial. Males had chosen small flat areas of rock surface, and a female would swim right against the rock “nest,” and deposit several rows of tiny pink eggs. The male would immediately swim close over the rock and fertilize the eggs.
We were all especially excited to find a large and busy “cleaning station.” One to two dozen barberfish were offering their services over a patch of rocks on the bottom. These small fish swim directly up to larger “client” fishes, picking off dead skin and parasites. The larger fishes, in this case rainbow chubs, don’t eat the “cleaners” because they benefit from their services. They signal their desire to be cleaned by darkening their colors, and tilting their bodies down. The cleaning station was extremely busy as several dozen blue rainbow chubs were cleaned in turn by the bright yellow barberfish.
Overnight we sailed from Costa Rican to Panamanian waters, and by mid-morning we were anchored off Isla Coiba. Birders went ashore on a nearby island and had wonderful luck; they found a lek of lance-tailed mannikins. In this species of forest bird, two or more male birds clear a small area on the forest floor, then vocalize, dance together, and make loud snapping sounds with their wings. It is thought that with more than one male, there is a greater chance of attracting the attentions of any available females for mating.
The underwater sights were even more exciting. While we were snorkeling and SCUBA diving at the tiny islet called Granito de Oro, we found fish engaged in many different and interesting behaviors. A large school of fish called spottail grunts maneuvered tightly together as a predatory fish called a blue crevalle jack swam around and through the school in search of a meal. No grunts left the protection of the school, and the predator did not get a meal - at least while we watched. Right on the bottom many sergeant majors were spawning. Unlike the grunts, these fish were being very territorial. Males had chosen small flat areas of rock surface, and a female would swim right against the rock “nest,” and deposit several rows of tiny pink eggs. The male would immediately swim close over the rock and fertilize the eggs.
We were all especially excited to find a large and busy “cleaning station.” One to two dozen barberfish were offering their services over a patch of rocks on the bottom. These small fish swim directly up to larger “client” fishes, picking off dead skin and parasites. The larger fishes, in this case rainbow chubs, don’t eat the “cleaners” because they benefit from their services. They signal their desire to be cleaned by darkening their colors, and tilting their bodies down. The cleaning station was extremely busy as several dozen blue rainbow chubs were cleaned in turn by the bright yellow barberfish.
