City in the Sea and Star Gardens

City in the Sea and Star Gardens are part of a documentary series called Wondrous Secrets of the Ocean Realm. This part of the series discusses the relationships between the animals on the reef. For example, the Grouper fish saw shrimp waving it’s antennas. The Grouper fish then turns colors to match the rocks and coral around them symbolizing safety to the shrimp. The shrimp then cleans the Grouper.

Color helps animals communicate with each other. The Coral Squid changes colors to communicate. Some scientist believe that squid have their own language. When a female is ready to mate, she develops a black line under she eyes. When a male squid sees this, he turns colors to fight off other squid.

City in the Sea and Star Gardens helped me answer my guiding questions because I was able to see the relationships of the animals in the coral reef. I was able to see animals depend on each other for food, cleaning, and life to the coral reef. Thus making the ecosystem of the coral reef work.


Life on the Coral Reef


This picture shows the important contributors in the ecosystem of the coral reef. Plankton are the Producers. Producers produce their own food. They do this by getting light from the sun and converting the sun’s energy, carbon dioxide and water to create food. This process is called photosynthesis. Phytoplankton also know as algae, is important to the food web of the coral reef because it produces 50% of the world’s oxygen in the air.

Next are the primary consumers. The primary consumers are also known as herbivores. They eat only plants. After the primary consumers are the secondary consumers. These animals eat the primary consumers. They are carnivores.

Decomposers complete the final stop in the food web. A decomposers job is to break down nutrients in the “dead” stuff and then return it back into the food chain cycle.

Healthy vs. Stressed Coral Reef Ecosystem


Many things can effect the ecosystem of the coral reef. The ecosystem is a very delicate system that needs all parts to continue to thrive. When one part disappears, the system is in jeopardy .

One thing that is effecting the coral reef, is coral bleaching. Coral bleaching is cause by climate change in the atmosphere. The coral reefs are in shallow waters near the surface, the weather has been getting warmer due to climate change, so the ocean has become warmer. Thus the very sensitive corals are being affected. Corals depend on their food called zooxanthellae that are deep in their tissues. When the water stays warm for multiple weeks, the zooxanthellae leave the tissues in the coral in thus making them white. Bleached corals are weak and cannot defend themselves from diseases.

Another thing that is effecting coral reefs is ocean acidification. This is also caused by climate change. Most of the carbon dioxide that enters the atmosphere goes into the ocean. Since the carbon dioxide in the ocean is increasing, the ocean pH level becomes more acidic. With acidification, the corals cannot absorb the calcium carbonate that they need to maintain their skeletons. Ocean acidification effects more than just corals. It effects other animals that need calcium carbonate to make their shells, like snails, urchins, and clams.