CORAL REEFS
by casey and galaxy
Climate of the Great Barrier Reef
2 seasons:
A dry season in the winter (May - October) with low rainfall
- A wetter season in the summer (November - April) with higher rainfall and temperatures
- GREAT BARRIER REEF WEATHER CHART
- CLIMATOGRAM
Four types of coral reefs:
- Fringing Reefs: Flat reef areas that "fringe" islands
Barrier Reefs: Skirt a landmass as well, but lie fairly offshore, usually separated by a lagoon or channel
Atols: Circular barrier reefs but without a central landmass
Platform/patch reefs: Irregular pinnacle or table-like features, often found in conjuction with atolls
Animals, Plants, and Fungi
- Hard corals are adapted to their environment because they create hard coral colonies that provide protection to animals that are involved in their survival. By providing an optimum environment for the other animals, it completes the food chain. Furthermore, its surface area allows for optimum surface area for photosynthesis, which is actually carried out by algae within the coral structure.
- Soft Corals: Soft corals are more common within shallower areas of the coast and have adapted bright colors and spiny textures to ward off predators, where hard corals use their stony structure to do the same. They thrive in shallow environments because they do not expand in the same way hard corals do, and they have lots of sunlight.
- Fish: For many fish a coral reef is not a permanent habitat. Rather, it is a sanctuary for early life and reproduction. For example, tuna have adapted to migrate during their lifetime and return to coral reefs to lay their larvae because of the shelter provided by the reef structure. Fish that do find their home in the reef are herbivores and eat the sea grasses that grow and therefore act as a built in lawn mower so that sea grasses don’t smother growing corals. It’s a constant food supply for the fish and a beneficial relationship to the coral.
Crustaceans: Crustaceans find their homes within the structures of the coral reef. Some fish periodically travel to coral reefs for cleaning, which is performed by crustaceans in a symbiotic relationship.
Reptiles: Sea reptiles, such as sea snakes, have adapted to have paddle-like tails and laterally compressed bodies, which improve swimming ability and allow for wiggling into small structures in the coral for protection. Sea turtles, like sea fish, are herbivores that feed on sea grasses and help to maintain the coral.
Humans
Many cultures directly interact with coral reefs. For example, Fijians ceremonially thank the reefs for offering protection from tropical storms, providing fish to eat, and bringing tourism to their economy. The reefs provide protein (fishing) to coastal inhabitants and offer pharmaceutical ingredients such as AZT, which is used to remedy people with HIV infections.
Unfortunately, commercial fishing, toxins in the ocean due to runoff and waste, and building on coral reefs have caused the deterioration of coral reefs over time and are destroying these vibrant and beneficial ecosystems. Our impact on the environment has led to global warming, and coral reefs are unable to adapt to these rapid increases in UV rays. The algae that is symbiotic with the corals needs a specific amount of sunlight and with the levels they’re experiencing “coral bleaching” is becoming a problem, as the vibrant colors affiliated with proper sunlight are used to ward off predators to the coral.
Sources
http://www.britannica.com/EBchecked/topic/137083/coral-reef/284956/Types-of-coral-reefs
http://wwf.panda.org/about_our_earth/blue_planet/coasts/coral_reefs/
http://www.coralfilm.com/about.html
http://video.nationalgeographic.com/video/oceans-narrated-by-sylvia-earle/oceans-barrier-reef
http://coral.org/coral-reefs-101/coral-reef-ecology/hard-corals/