The Bacterial Community Of The Coral Holobiont

Most reef-building corals contain photosynthetic algae, termed zooxanthellae, that live in their tissues. The corals and algae have a mutualistic association. The coral provides the algae a environment and compound

The Ocean is a miraculous place filled to the brim with foreign creatures and wondrous wildlife. From the Great Orcas of the Antarctic waters to the minuscule plankton, these marine life conquer the ocean's depths, but it's not just the creatures that reside here. Coral occupy their fair share of space upon the ocean's floor filling the waters with their glamour and residential charm for those in search of shelter.

The Coral Reefs are limestone formations that are produced by living organisms. They are found in shallow tropical waters. The predominate organisms that make them up are stony corals, which are colonial cnidarians that secrete calcium carbonate (limestone) as an exoskeleton. Calcium carbonate is also deposited by other types of marine organisms such as tube-building annelid worms but any reef formed by a biological community is called a coral reef. These skeletons accumulate due to the tides and create a formation that supports the living coral as well as the highest species diversity of all explored marine habitats. Reefs are found between the latitudes of 30°N to

Coral reefs exist all over the world and are generally known as being one of the most diverse, intricate and beautiful of all existing marine habitats. They have many varying structures which are developed by algae and are symbiotic with various reef building corals which are referred to as, zooxanthellae (algae). There are many other factors such as, coralline algae, sponges and other various organisms that are combined with a number of cementation processes which also contribute to reef growth, (CORAL REEFS, 2015).

Coral bleaching is normally characterized by the expulsion of the zooxanthellae algae, loss of algal pigmentation, or both. Coral bleaching events have had serious effects on corals and reefs worldwide. What is crucial to the understanding of zooxanthellae expulsion and bleaching is how the density of zooxanthellae within the coral is changing, if at all, under the prevailing range of environmental conditions (Gates and Edmunds, 1999). Over the last twenty years, there has been a dramatic increase in both the frequency and intensity of coral bleaching events. Sixty major bleaching events have been reported between 1960 and 1979, whereas only nine were reported prior to 1979 (Huppert and Stone, 1998). Given the dependence of the coral on this symbiotic algae, it is important to determine the cause of these bleaching events. According to Helvarg (2000, p.12):

Since early 1998, climate change has been demonstrating its effects in increasing the ocean 's temperature (West & Salm, 2003). Warm water stress corals causing the phenomenon known as coral bleaching, by which expulsion of colourful symbiotic algae the zooxanthellae, vital for

The purpose of this research is to apply the knowledge learned about the ecology of the Hawaiian Coral Reef to a real-life situation. The coral reef stretches over 1,000 miles in the Pacific Ocean. In the Pacific Ocean, near the 124 islands of Hawaii, is the Hawaiian Coral Reef, which covers nearly 1,200 miles. Out of all the coral reefs in the world, the Hawaiian reef consists of 85% of all reefs. Coral Reefs are made of organisms, coral, and limestone skeletons. 25% of organisms are not existent anywhere else in the world. Abiotic factors are nonliving things, and abiotic factors of a coral reef are depth, light, wave motion, salinity, and temperature of the ocean. Biotic factors, living factors, is the whole coral reef,

The most represented classes were Acidobacteria and Alphaproteobacteria, which together comprised almost 30% of all bacterial amplicons, followed by the considerably lower representation of Deltaproteobacteria, DA052, and Sphingobacteria (Table 1S). Members of the dominant classes Actinobacteria, Alphaproteobacteria, and Sphingobacteria showed similar patterns between sample sites. However, Deltaproteobacteria had a higher relative abundance at RP in comparison with SB or HH1, and Elusimicrobia was in higher abundance at RP than at HH1. Levels of Nitrospirae and Spirochaetes were the highest at RP than in all other samples.

The purpose of this lab is to isolate photoheterotrophic bacteria using an enrichment culture from a sample of marine sediment. The enrichment culture provides the photoheterotrophic bacteria with specific conditions to promote growth.

The coral reef surveyors were instructed to find the best sites that they believed had the most living coral and were thought to be least affected by human activities. This would allow Hodgson to determine if human activities were having an appreciable effect on the supposed pristine coral reefs, which were distant from urban centers. The invertebrate survey was undertaken at two depth intervals of 3m and 10m. Four 0.5 m wide by 20 m long belts were placed on the coral reef. Over a period of 3-5 minutes the observers counted the number of invertebrates found on the belts. The coral survey was performed, by placing four 20 m long belts on the coral substrate. At 0.5 m intervals the substrate on which the belts were lying was examined and recorded.

Compared to corals in the controlled environment, corals exposed to oxybenzone showed significantly higher concentrations of viruses, especially around the branches (Danovaro, 2008). Oxybenzone activates viral reproduction in zooxanthellae until its host cell explodes. (Tibbets, 2008). The virus released into surrounding water after the dinoflagellate explodes may also pose a hazard of contamination for nearby coral communities (Tibbets, 2008). Oxybenzone induced viral infections may not solely result in coral bleaching, but it is another factor that weakens the overall health and resilience of

The recent research of the Astraea deals with different coral diseases. One of the most popular is the black band disease which infects large reef formation corals. This disease changes the whole reef geologically and ecologically. There have been new discoveries on the bacteria responsible for the black band disease. The water around the coral that has been infected has corallinae in it which makes it seem it is related to the cause of the disease. There is still more research needed to confirm the relation of the corallinae and the black band disease.

Broken and abraded coral has been clearly injured and or killed. However this abraded coral is less resistant to diseases and will have slower reproduction and growth due to redirected energy.24 Originally studies focused on coral breakages, however more recent studies have found that just the re-suspension of sediment can affect the health of reef. The removal of sediment from the coral surface results in the redirection of energy and makes the coral more vulnerable to disease.33 The study of this is more difficult and less reliable as weather has a huge impact on sediment suspension. Observations by Barker and Roberts accounted for sediment re-suspension, but the extent of damage caused to the coral was not

Coral reefs contain symbiotic algae called zooxanthellae which gives the coral its healthy brownish color. The algae "utilizes sunlight and the coral animal's respired CO2 to produce energy rich compounds that feed the coral host" (AIMS, 2003). When stress factors such as "heat, solar radiation, pollution, reduced salinity and changes in oxygenation" occur around the coral, bleaching can begin (Dennis). When bleaching occurs, the algae, which create nutrients for the coral to feed from, is released due to stresses to the reef. Thus the coral starves and its white calcium carbonate skeleton of the coral becomes visible (AIMS, 2003). But one of the main stresses that contributes to the lifeless white appearance of the coral is the warmer temperatures of the sea surface water.

     Coral reefs are one of the oldest types of living systems on earth, and certainly one of the most spectacular (Goreau, 1987). They are massive underwater structures formed by the limestone skeletons of tiny invertebrate animals. Reefs house a greater diversity of body forms, chemistry, and animal phyla (thirty-two compared to the eight that inhabit the most biodiversity ecosystems on land). Phyla comprise the second largest category of living things, after kingdoms.