Showing posts with label coral nursery. Show all posts
Showing posts with label coral nursery. Show all posts

Thursday, September 4, 2014

Thomson Reuters Donation Aids Malaysian Marine Science



Once again we have a look at the activities of our young marine scientists. As their internships wind to a close most have volunteered to stay on at the Andaman through the busy Christmas/ New Year period.

 They will continue to be hosted by the Andaman Resort and their allowances and research materials costs will come from the generous donation of Thomson Reuters.

Young marine biologists have turned the Coral Nursery into a major attraction for overseas guests.
Determination of growth rate based on linear extension growth of
massive corals by using UV-Light.

by Mohammad Ikram Bin Mohammad Naser



The annual-bands of coral core are the bands or “rings” that formed on the skeletal structure which is similar to the trunks of tree. The bands represent the different year and the skeletal structure also exhibit a regular periodic variation in bulk density reflecting seasonality. The annual-band of the coral skeleton shows the historical record in the different environmental condition. Most of the element and compound that expose to the coral will trap within the aragonite during deposition and this condition will capture a record (Readman et al., 1996).






This study aims to know the growth rate of the massive coral (Eg: Porites, Favia, Goniopora) at Datai bay by using UV light for chronological banding patter that have inside the coral skeleton . The alternating density (high density and low density) represent a year of the coral growth .

The massive coral species around the bay are survey first. Then, the selected massive coral will be cut using metal saw, where the slice/cutting is perpendicular to the main vertical growth axis of the colony. Then, the coral skeleton will let to dry and linear extension analysis will be carried out.

The linear extension method is to identify the year bands or the growth rate of the coral. The coral core will be observed under UV light lamp in a dark box  to observe the dark and light bands (the chronological banding pattern). The wavelength of the UV light is 254 nm. When the bands are revealed, the growth rate of the coral will be calculated for Linear Extension Rate. The linear extension rate will be calculated by using a ruler with 0.1 cm accuracy for each year.



Photo illustrating growth rings courtesy USGS



Monitoring of Coral Health in the Coral Nursery
by Cherylynna Roland




All living things, including the corals are susceptible to diseases, making monitoring of their well-being important for further development of nursery maintenance strategies. My task involved using Indo-Pacific Coral Health Decision Tree to identify known causes of lesions and described lesions of unknown causes through visual cues, manifested as alterations in color, shape, size, tissue loss and also growth anomaly of the polyps or skeleton of the corals (Work & Rameyer 2005).  

The growth of lesion was measured using calipers and analyzed with Coral Point Count with Excel extensions (CPCe V3.4). In the Coral Nursery, the lesions are due to abrasion from neighboring corals, accumulation of sediment on the coral colonies, and infestation by tube-building worms. I tested two strategies to see whether recovery is possible, by isolating the coral with lesions under the shade, with adequate water flowing through them, and by fragmenting the healthy coral and transplanting them in mid-water to avoid contact with sediment and allowing more efficient water exchange surrounding the fragmented corals. After one month, the corals are showing good signs of recovery, which can be seen by re-growth of polyps on the once exposed skeleton.  







In the ocean, the ability of reef recovery is important, as a research by Dixson et.al (2014) shown that both coral larvae and fish are attracted to the smell of a healthy reef, encouraging their settlement, and thus making the reef ecosystem complex. 


Young guests gain an appreciation of marine life at fish feeding time.



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Thursday, August 28, 2014

Andaman and Thomson Reuters Sponsor Marine Scioentists





Dr Gerry introducing the students to the Coral Nursery program.


We have just completed a three months internship program with students from UKM (National University of Malaysia) and UMT (University of Malaysia Terrenganu). 

 Seven students were hosted by the Andaman Resort with the provision of food, lodging, and supervision.  Small allowances and minor research equipment were provided by the nature Fund through the contributions of Thomson Reuters.
Coral transplanting with guests was a daily occurrence.

 Below are summaries of several of the projects. The remainder will follow in the next posts. All of the numerical results are able to be published through the University giving the graduates evidence of their research ability when job hunting.
A guest is guided through the nursery by an intern marine science student.

But it wasn't all about research. Interns spent long hours transplanting corals and working with guests. Self confidence improved as did language skills. The program was a great success.


Abundance of coral using quadrat method at Datai Bay, Langkawi

by Noor Zalikha Mohamad




The mini project was done on July and August, 2014 during the low tide. The sampling was done by using 2X2 m quadrat. Each of the division of the quadrat represents about 4% from the total percentage of 100%. 

The quadrat was placed at the first starting point which is in front of water sport and then  along the beach toward Anak Datai. There is 10 m distance between quadrats and three transect were done. The total quadrat samples completed were 45. 

The result shows that the most abundant material is sand/dead which is present the highest number (46.04%-66.03%) in all three transects. Most is dead coral with algae and also dead coral skeletons. 

The percentage of live coral is small (less than 5%) compared to dead coral. However the most abundant coral life form from the project is massive coral which is contribute the highest density among the life coral. Other corals are coral foliose, coral encrusting, coral submassive and also little portion of acropora branching. Other than coral, the macroalgae also has been found during conducting the project. Most macrolagae that has been found is Halimeda sp. and others is Padina sp.



The changes of sedimentation rate in Teluk Datai
by Chai Wan Jin



Nowadays, human activity has tended to increase terrigenous sediment loadings and re-suspension in the coastal waters  in all the coral reefs countries. This is because sediments from terrestrial origin were found is the main factor that leads to the decrease in growth of most corals (Heiss, 1996; Crabble & Smith, 2005). The high sedimentation rate in the coral reef areas would smoother the coral surface, reduces regeneration from tissue damage, reduces growth (Lough & Cooper, 2011) and thus bring to mortality of coral reef (Erftemeijer et al., 2012). 

Teluk Datai is a high sedimentation bay where Porites coral is the dominant species found in the reef due to the tolerate behaviour of the coral species to the high sediment content in the water (Abdullah et al., 2011). Therefore, the objectives of this study are to compare the sedimentation rate in October 2013, January, April and September 2014 and to study the changes of sedimentation rate in the mini-ARMS and ARMS during spring and neap tides.
Sampling will be done using sediment trap during spring and neap tides in Artificial Reef Module, and mini Artificial Reef Module in August (Table 1).  

The sampling is not yet complete because there is one more spring tide in this coming 26th and 27th August. Therefore, the sampling analysis will be done in the coming 1st September at Universiti Malaysia Terengganu.

The data in the previous sampling shows most of the sedimentation rate exceeded the coral tolerance limit, 50 mg/cm2/day in October 2013. However, it shows a better result in January 2014, where only Princess Bay had the sedimentation rate higher than the coral tolerant limit and the results show even better in April 2014 (Figure 1). These results could be due to the raining season in October and the strong wind from northeast in January which would create the most intense near-bed current and eventually would bring re-suspension from the bottom especially in the shallow water. 


 Measuring the rate of spread of a coral disease.










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