Marine Biology Day 4: 7-16

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The day began with a rough thunderstorm which cleared just in time for our morning dive. We proceeded to dive at the edge of a coral reef overlooking the deep blue. We followed the wall of the reef and observed some curious pufferfish hiding shyly behind large clumps of coral. On the second dive that morning, we explored a shallow and sandy scattered reef which was personally one of my favorite dives. During this dive, I was able to observe large schools of tiny fish nestled around the pockets of coral and rock. These vibrant colors caught my eye and I decided to approach them. As I assumed, the large group quickly dashed away and found shelter within the rocks. However, since the water was quite calm today, I was able to effortlessly float above the once startled group of fish. Slowly but surely, the school emerged once more, and didn’t even seem to realize that I was invading their space. This made me think back to other times in which I have snorkeled or swam with fish, and they didn’t have the same comfortable attitude. This led me to wonder how desensitized these fish were to encountering people. After getting over the initial shock of my presence, they didn’t seem to view me as a threat. It reminded me of one of the many ways humans can have an effect on an environment. By introducing ourselves as a non threading part of an ecosystem, the native species (some of them at least) seem to recognize that we are not a threat. Later this afternoon, we embarked on a trip to the Grand Cayman Turtle Center. Here we first encountered a large open tank full of green turtles. This tank was meant for breeding. As soon as we arrived, the turtles flocked towards the walls, hoping we would be giving out food. This to me was another perfect example how humans can have an effect on a species. These turtles in the wild are not dependent on humans for food. Frankly, if a human tried to offer food, it would most likely swim away before the person got too close. Yet in the sanctuary, the turtles were completely used to the idea of humans providing food. In a way, this is very similar to the fish I encountered. Both species have become accustomed to the idea of a human presence. In turn, the turtles for example, might suffer greatly if ever released into the wild. The amount of time spent reliant on humans for food could offset their natural hunting instincts. While the schools of fish may be less cautions with other new predators. Both of these human effects could have detrimental effects on the species by changing their fundamental instincts.

Clark Brown