I recently took my Saint Benilde students for a field trip in San Juan Batangas. There we had the chance of looking at the marvels of nature at the marine sanctuary at Laiya. While the corals we saw were not as beautiful as in other places, they remain remarkable specimens of the species. This prompted me to read more about corals in the interest of teaching it to my 1st grade daughter who studies biology.
Corals are made by coral polyps. These are coelentrates or species with a hollow middle. They are related to sea anemonies, jellyfishes and hydras. These animals have little tentacles and have a little hole in the middle for ingesting food. Coral polyps are special because they are colonial. These little creatures group together and secrete limestone to create reef structures. Their workmanship rivals the craftsmanship of Ferrari parts! Not bad for creature with no brains. They painstakingly build a 1cm growth of coral for about a year. (Just imagine if you break a 10cm segment…10 years work!!!)
I would consider them keystone species’ because of the fact that the reef ecosystem is built on them. The presence of the polyps attract dinoflagellate algae known as zooxanthellae with whom they share a symbiotic relationship. These algae, fondly called zooks, give corals their peculiar color. Zooks also attract primary consumers such as small fish, starting of an entire food web that sustains the ecosystem. That sad thing is that when our garbage, especially plastic bags, covers the coral. These kill or drive away the zooks which in turn kill the coral polyps. This is evident with coral bleaching. With the mortality of these species comes a collapse of the food web eventually leading to the reduction of our fish supply.
Considering that food for humans is at stake, we really need to reduce our usage of plastic bags to ensure our kids will have a steady supply of fish in the future
