Current/Major stresses-Human impacts on Biome by Danielle M

Studies state that 10% of our world's coral reefs have already been destroyed. It has also been stated that the reasons as to why our reefs are being destroyed are the following:

Cyanide fishing- Fishermen have been caught squirting cyanide into the reefs. Cyanide is used to capture live fish for aquariums. Due to the usage of Cyanide both the reef and many of the invertebrate species living in its ecosystem are being poisoned.

Pollution- Due to the fact that Coral reefs are so near to the shoreline they constantly have to face the pollution. Pollution with the sewage, fertilizers, pesticides and oil spills that are found on land that bleed out into the ocean. A study found at the University of Illinois said that human sewage and shipyard trash have made the coral reefs highly vulnerable to a deadly disease called the "black band disease."

Global warming- Global warming causes ocean temperatures to rise, and with this happens coral loses the zooxanthellae that gives it its nutrients and colors. This causes the coral to starve and turn white, called "coral bleaching."

Overdevelopment- There is more pollution in the water due to the fact that humans are building closer and closer to the shoreline. Ship travel has also become very damaging to the reefs.

Reckless recreation: People alone are a threat to coral reefs. Tourists collect pieces of coral as souvenirs, boats sometimes anchor on reefs, divers sometimes entangle their gear in reefs this damages them in the procces.

(Period 4 - Group 5)

Services of Coral Reef:
The coral reef serves as the safe haven to many animals of the ocean, ranging from tiny fish, to sponges, to large eels. It provide organisms of the ocean with rich nutrients it produces, although they are found in nutrient-poor waters. They use nutrient recycling to help them flourish in the waters they live in.coral_reef_1.jpg

Major Products/Exports:coral_reef_1.jpg
Many products of the coral reef are exported as decorative artifacts. It can be used for d�cor items for aquatic aquariums, or in many cases, jewelry for women and men. There are also exported foods, even medications which contain coral. Although coral can be exported as various merchandise, the primary product of coral, in the aquarium industry, is fish. However, the world market is limited in the diversity of collected species. For example, among 4000 coral reef fish species, only 200�300 are exploited.

Goods:
The good outcome of the coral reef biome, is that is mainly provides a home to a variety of organisms in the Earth�s oceans. While providing shelter, coral reefs set up an array of colorful patterns which serve as a beautiful decoration to the waters. Due to their vast biodiversity, many governments world-wide take measures to protect their coral reefs.
Links used:
  1. http://en.wikipedia.org/wiki/Coral_Reef
  2. http://www.nceas.ucsb.edu/nceas-web/kids/biomes/coral.htm

Responsibilities of Group 5 - Period 4

Jordon N: Location/Geography
Jordon N: Climate
Nathan J: Vegetation Types & Adaptations
Patrick R: Animals & Adaptations
David W: Goods/Services/Exports
Danielle M: Human Impacts/Stresses

Animals of coral reefs
30 species of whales and dolphins are known to live on or visit coral reefs


Dwarf minke whales visit the Reef every year in June and July. They are baleen whales, which means they feed by straining tiny plankton and krill through comb-like plates on their upper jaws.
Humpback whales also pass through every year. They are the fifth largest animal in the world, as big as 600 people.
Irrawaddy and Indo-pacific humpback dolphins live close to the coast of Queensland all year round. They feed on fish in shallow waters, especially in estuaries or river mouths.

Large populations on dugongs live on coral reefs


Dugongs grow to about 3m long, can weigh 400 kg and live to 70 years old. Dugongs are more closely related to elephants than they are to other marine mammals such as whales or dolphins.
Dugongs have a single calf when they are between 6-17 years old and then have calves only once every 2.5 to 5 years.
Dugongs eat seagrass, and actually 'farm' tasty types of seagrass by cropping their preferred plants.



Over 200 species of birds live off of coral reefs.


White-breasted sea eagles live on the coast and islands. They find it hard to take off from the water, so they fish by snatching their prey from the water's surface.
The Roseate tern migrates from the islands of the Great Barrier Reef as far as Japan, and is protected by the Japan Australia Migratory Birds Act.
Raine Island is one of Australia's most significant seabird rookeries and has the greatest number of nesting species .



6 species of sea turtles in on coral reefs.


Six of the seven species of sea turtles in the world are found on the Reef: Green, Leatherback, Hawksbill, Loggerhead, Flatback and Olive Ridley.
Sea turtles lay their eggs in sand. The temperature of the sand determines the sex of the young turtles. Cooler sand produces male turtles, while warmer sand produces females.
Sea turtles can lay up to 100 eggs at a time.
They become sexually mature at 30-50 years and can live for up to 100 years.
Hatchlings are carried out to sea on ocean currents, and can travel thousands of miles around the ocean before they are fully grown. When they reach breeding age, they return to the area where they hatched to lay their own eggs.
The Leatherback is the largest sea turtle. The heaviest Leatherback turtle ever measured weighed 916kg.






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1500 species of fish


The oldest fish on the Great Barrier Reef would probably be a red bass, which can live to more than 50 years old.
The biggest fish on the Great Barrier Reef would be the visiting whale shark which can grow to about 12m long.
Five of the seven species of coral trout occur on the Great Barrier Reef. Coral trout change sex as they grow . They start life as females and become males as they get larger. The average length at sex change is 42 cm. Common coral trout can live for about 16 years.






5,000 species of molluscs live on coral reefs


Giant clams can grow to be more than 1 metre long and can be at least 70 years old. They are the largest bivalve mollusc that has ever existed on the planet.
Most giant clams are simultaneous hermaphrodites the same animal is both sexes at the same time.
Cone shells shoot their prey with a modified tooth. They can be highly poisonous and a few species (which usually eat fish) are harmful to people.
Nudibranchs are a type of sea snail which only have a shell when they are tiny larvae. Adult nudibranchs have a multi-coloured mantle instead of a shell. The bright colours warn predators to stay away.
Molluscs have feathery gills through which they can absorb oxygen from the water.
Octopus, cuttlefish and squid are also types of mollusc.




400 species of coral live on the Great Barrier Reef


Corals are colonies of made up of tiny animals called polyps. Hard corals have polyps with 6 tentacles, or multiples of 6 tentacles. Soft coral polyps have 8 tentacles.
The oldest coral on the Great Barrier Reef would be a Porites sp. and is probably about 1,000 years old. Old colonies of this species are the size of a small room. These corals grow at about 1 cm in height per year and their skeleton reflects the weather conditions at the time of the growth. Hence large corals which are hundreds of years old can provide information about water temperature and rainfall patterns that pre-date European settlement.
Tiny algae called zooxanthellae live in the flesh of most corals. The algae photosynthesise and transfer energy to the coral. Therefore, coral reefs (which are built mostly by these corals) are generally confined to shallow waters because like other plants, the algae require light to survive.
Coral spawning happens on only a few nights of the year. Corals release their eggs and sperm into the water, where they will either meet and be fertilised, or become food for other Reef animals.

Vegetation of Coral Reefs

Of some 60 species of seagrass around the world, there are 30 in Australia and 15 in Queensland waters.
Starfish in seagrass are different to seaweeds and algae because they have true roots and are flowering plants. Seagrasses are the only flowering plants in the sea. They are important food for turtles and dugongs. Some seagrass meadows are so extensive they can be seen from a space shuttle orbiting earth.
500 species of seaweed or marine algae live on the Great Barrier Reef. Most seaweeds are not poisonous to humans but a few, such as Caulerpa, are poisonous to grazing animals and survive on the reef without being eaten. Seaweeds contain many compounds useful to humans carrageenans or agar (from red seaweeds) or alginates (from brown seaweeds) are used in ice cream, instant puddings, salad dressings, printers ink, cosmetics, in pharmaceuticals and to coat pills.

Coral Reef Climates

Coral reefs start out small and grow about half an inch a year, but if undisturbed by man they can grow to be quite large. The Great Barrier Reef off the northeast coast of Australia is 150 km (93.2 mi) wide and 2000 km (1,242 mi) long! The tan parts of the reef are the shells of dead coral polyps and the colorful parts are the living parts of the reef.

Reefs grow best in sunny, shallow, clear water. The water must be clear and shallow so that the reef can get lots of sunlight. They rarely grow deeper than 40m and they prefer salt water, doing poorly in areas where there is a lot of river runoff due to the freshwater as well as the silt which can cover a reef or muddy the water blocking the sunlight. The best temperature for coral reefs is between 25 and 31û C and the best salinity is between 34 and 37 parts per 1000. The appropriate temperatures and salinities are most often found in the tropics.

Reefs grow best in sunny, shallow, clear water. The water must be clear and shallow so that the reef can get lots of sunlight. They rarely grow deeper than 40m and they prefer salt water, doing poorly in areas where there is a lot of river runoff due to the freshwater as well as the silt which can cover a reef or muddy the water blocking the sunlight. The best temperature for coral reefs is between 25 and 31û C and the best salinity is between 34 and 37 parts per 1000. The appropriate temperatures and salinities are most often found in the tropics.

There are three kinds of coral reef--the fringing reef, the barrier reef and the atoll.

Types of Reef

Fringing reefs grow in shallow water along the shore and prefer arid climates with limited river runoff. Fringing reefs are platforms that are continuous with the shore. That means they grow right up to the edge of the shore, like in the picture above.

Barrier reefs are separated from the shore by a wide, deep lagoon. They grow only when there has been a change of sea level on the adjacent coast. This occurs when a fringing reef grows upwards so that it can stay near the surface of the water. Coral reefs like to grow just below the waterline so that they have the best access to the sunlight. It is best if a reef grows at the same rate as the rise of the water. Barrier reefs also grow where the land is sinking faster than the water. The number of barrier reefs has increased dramatically as the greenhouse effect has warmed up our atmosphere causing the water levels to rise.

Atolls are reefs surrounding a lagoon. They are created when an island surrounded by barrier reefs sinks below the ocean surface, leaving a circular reef, called an atoll. Atolls are also created when water levels rise to cover an island and the surrounding reef grows to keep up with the surface of the water.