The fine coral sand that alternates with rocky promontories along the Galapagos coastline supports an entirely different fauna. There is no spray zone on the beach because the waves roll in smoothly, dispersing a thin sheet of solid water to their highest reaches. There are crabs, shore birds, sea turtles and sea lions who use the beach to either feed, nest, breed and mostly important, rest.
The beach we visited today is located at Gardner Bay. This is one of our most exciting experiences, not only because of the presence of many sea lions, but because of the very fine sand on this beach, which is mostly composed of coral.
Corals are simple in design and nearly identical to sea anemones; the main difference is that corals secrete a calcium carbonate exoskeleton. Many are colonial, made up of hundreds of thousands of individual fleshy polyps that are housed in rigid cuplike corallites. The interconnection of these entities is referred to as a colony. Reef building corals in the tropics is greatly attributed to the presence of endosymbiotic algae, known as zooxanthellae, living within the gastrodermis of the coral. This relationship is mutualistic, since the zooxanthellea provide the coral energy through photosynthesis and also oxygen for respiration and remove toxic wastes such as carbon dioxide from it. They are known also to mediate the calcification process. If corals expel their zooxanthellea, the rate of skeleton formation is reduced to almost zero! For the algae the coral provide a save environment, free from predation and a continuous source of scarce nutrients.
These minute creatures posses stinging cells called cnidocytes, within the cnidocyte is the nematocysts which are tiny coiled pointed barbs contained in a sac of fluid ready to be expelled to paralyze, kill, and entrap passing prey!
We do not worry about the presence of corals on the beach, for only the remnants of the" house" of the corals are found. Fishes such as the parrotfish prey on them. After the process of digestion, the coral is liberated into thin particles, which are then washed to shorelines providing us with beautiful sandy beaches.
Today, I wanted to share the tranquility that our guests experience on such marvelous beaches.
