Shiran Chamika | Ocean University of Sri Lanka (original) (raw)

First Authorship by Shiran Chamika

Coral reefs are threatened by the number of natural and anthropogenic impacts. Increasing body of... more Coral reefs are threatened by the number of natural and anthropogenic impacts. Increasing body of literature suggested that the coral mortality is due to various changes associated with water chemistry and microbial activity. A detail study was conducted from 12th of February 2014 to 31st of October 2014 to understand the present status of Paraviwella reef, Tangalle Sri Lanka (6° 01' 17.07 " N, 80° 48' 01.21 " E) with relation to water column microbes, reef fish, corals and algae. Monitoring data showed that substratum composition dominated by coral (64.7 ± 18.9%) and algae (19.2 ± 13.4%) where the reef fish community dominated by herbivores fish [herbivores (51.7±1.7%), carnivores (30.9±5.8%), planktivory (10.6±4%) and omnivores (6.8±6.4%)].Coral algae recruitment was dominated by fleshy algae and coral algae interaction also noted. Water quality parameters were also recorded within suitable range [Temperature=29 ± 1°C, Depth=54 ± 17 cm, Salinity=34 ± 1ppt, Turbidity=3 ± 0.6 NTU, Dissolved Oxygen=8.6 ± 1 ppm). Under this situation, planktonic microbial abundance was 4.5×106 ml-1. In addition to that the microbial score (MSVibrio) also determined by using Vibrio culturing techniques (MSVibrio= 0.99). However the recruitment of the algae is high, the ecological balance is controlled by herbivorous fish and therefore coral cover remain dominant and overall results indicated that the Paraviwella reef is a healthy reef (MSVibrio ~ 1). Continuous monitoring is undergoing to explain the mechanism of Paraviwella reef with advance bio-geochemical methods and microbial methods.

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Coral reefs ecosystems are sensitive to global changes in climate and human activities. The rela... more Coral reefs ecosystems are sensitive to global changes in climate and human activities. The relationship between microbial activity and chemical substances available in the water column due to sensitive process from climate to human activity is not very clear. This area of research is needed to understand the ecosystem processes for conservation initiatives. Therefore the study aims to identify the current status of shallow fringing reef Paraviwella (FRP) at Tangalle South Sri Lanka (6° 01’ 17.07” N, 80° 48’ 01.21” E) from 12th of February 2014 to 31st of September 2014, with reference to microbial activity and quality of water in reef water column. Benthic assessment shows that the FRP is dominated by living corals (57.6 ± 11.8%) and algae (22.3± 12.2%).Chemical conditions of sea water were measured, following parameters were used to assess viz. Dissolved oxygen (DO), Temperature (T), Salinity (S), Depth (D) and Turbidity (Tb).Bacterial abundance was measured using direct counting method (Epifluorescent microcopy). Also culture experiments to show the microbes selective agar plates (Thiosulfate Citrate Bile salts Sucrose (TCBS agar) agar for Vibrioand, Xylose Lysine Desoxycholate (XLD agar) agar for Salmonella.) Results disclosed that water quality (DO=8.60 ± 1.12 ppm, T=29.3 ± 0.3°C, S=34 ± 1ppt, D=54.1 ± 17 cm, Tb=3.1 ± 0.6 NTU) and microbial abundance (MA) (mean Total MA= 4.5×106 ml-1, mean Vibrio abundance= 65.75 CFU/ml-1 and mean Salmonella abundance = 1 CFU/ml-1) at FRP were within the range of suitable condition for growth of corals and other associated organisms. Continuous monitoring is essential to describe the situations with relation to changes of climate of human activities.

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Co Authorship by Shiran Chamika

Coral reefs have suffered from a range of impacts from local anthropogenic influence to global cl... more Coral reefs have suffered from a range of impacts from local anthropogenic influence to global climate change. In recent years these impacts have led to changes in coral community structures from coral reefs dominated by living corals to dominance by fleshy algae (which is called phase-shift). These changes effect the overall trophic structure of reefs. Monitoring is essential to identify these changes and where necessary the possible responses within Sri Lanka. The present study was conducted at Paraviwella reef, Tangalle (Location GPS: 6001'17.02 " N, 80048'01.91 " E) from 19th of February to 31st of May 9014 (The mean water depth was 54 ± 17 cm; the mean temperature was 29 ± 0.30C). The objective of the study was to find out the present status and composition of sessile benthic life forms (corals and fleshy algae), reef fish with relation to microbial abundance. This data will be useful to understand the prevalence and trends from impacts. The main methods for the assessment of benthic composition (i.e., Line Intercept Transects for percentage cover, n=3, 20m each) and abundance of dominant reef fish (Visual fish counts along belt transects to determine percentage abundance, n=3, 25m each) were conducted according to Australian Institute of Marine Sciences procedures. Microbial Abundance was determined using epifluorescent microcopy techniques. The results show that benthic composition was dominated by living coral (57.58±11.77%) and fleshy algae (22.25±15.46%). Percentage cover of non– living components such as coral rubble, sand and rock were recorded as 20.17± 8.52%. Pocillopora damicornis and Caulerpa recemosa were the dominant sessile benthic life forms represented at the reef site. Among the fish species, a higher percentage was represented by herbivores (46 ±7%) and carnivores (40±10%). Lower percentage represented by omnivorous and planktivorus fish (3±1% and 9±1% respectively). At this condition at Paraviwella reef water column mean microbial abundance was 4.5×106 ml-1. These results suggest that coral algae interaction is maintained by reef fish grazing. The recorded abundance of bacteria at this status and could be used as a reference value to determine the trends pertaining to phase-shift at Paraviwella reef.

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Reef fish abundance and their feeding in relation to habitat characteristics are essential to und... more Reef fish abundance and their feeding in relation to habitat characteristics are essential to understand the function of food web in coral reef systems. We selected Paraviwella reef, Tangalle, South coast of Sri Lanka (6 0 01'17.09 " N, 80 0 48'01.21 " , Depth = 54±17cm) from 12 th of February to 31 st of May 2014 as a natural mesocosm to study the reef fish abundance at different times of the day [morning–TM (7am-9am) , afternoon–TA (11am-1pm), evening–TE (3pm-5pm)]. The aim of the study is to determine the reef fish abundance with reference to their feeding type(herbivorous-HB, carnivore–CV, omnivores–OM and planktanivor–PL).Underwater visual and video surveys were performed along permanent belt transects (n=3, transect length =25m, observation time = 30 min) to obtain data on fish abundance. Fish transect census disclosed that percent abundance for different feeding behaviors viz. herbivores (51.7±1.7%), carnivores (30.9±5.8%), planktivory (10.6±4%) and omnivores (6.8±6.4%). Fish feeding observations during the study indicated that herbivorous and carnivorous species were dominant in the study area. The herbivorous assemblage was dominated by four species of damselfishes (Abudefduf vaigiensis, Chrysiptera brownriggii, Pomacentrus chrysurus, Abudefduf sordidus) and five species of surgeonfishes (Acanthurus bleucosternon, Acanthurus lineatus, Acanthurus triostegus, Acanthurus nigricauda, Ctenochae tusstriatus).The percent abundance percentage of herbivorous fish families was highest during the evening(55.1±11.3%) compared to the morning(48.3±11.4%) and the afternoon(52.1±11%). Statistical comparison (two sample t-test) showed that, there was no significant difference in abundance between time periods (p>0.05). The carnivorous assemblage was dominated by twelve species of wrasses (Halichoeres hortulanus, Halichoeres marginatus, Halichoeres nebulosus, Halichoeres scapularis, Halichoeres vroliki, Thalassoma hardwicke, Thalassoma jansenii, Thalassoma lunare, Stethojulis trilineata, Labroides dimidiatus, Gomphosus caeruleus) and four species of butterflyfishes (Chaetodon auriga, Chaetodon collare, Chaetodon decussatus, Chaetodon citrinellus). The percent abundance percentage of carnivorous fish families were higher during the morning (34.9±3.8%) compared with the afternoon (29.9±4.2%) and the evening (27.6±5%) but showed no significant difference (Two sample t-test, p>0.05). This study suggest that more detailed studies are necessary to find out the connectivity of reef fish to food web function in a coral reef.

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Shallow reef habitats dominated with living corals is relatively accessible all times of the day ... more Shallow reef habitats dominated with living corals is relatively accessible all times of the day and could be useful to consider as a natural mesocosm. This study was conducted at Paraviwella near shore reef patch, Tangalle, Southern Sri Lanka (6° 01' 17.07 " N, 80° 48' 01.21 " E) from 25 th April 2014 to 10 th September 2014 to examine the current status of the substratum composition. Line Intercept Transects (LITs) method was used for benthic composition study (number of transects = 6, length = 25m and area 3500 m 2). Temperature (T), Salinity (S), Turbidity (Tb) and Dissolved Oxygen (DO) were measured in sea water collected from transect locations. Results disclosed that sea water quality at Paraviwella reef were within the suitable condition for growth of corals and other associated organisms (T=29 ± 1°C, D=54 ± 17 cm, S=34 ± 1ppt, Tb=3 ± 0.6 NTU, DO=8.6 ± 1 ppm). Transect study showed that living corals (64.7 ± 18.9%) and algae (19.2 ± 13.4%) were dominant life forms represented by higher percentage cover at Paraviwella. Also rock (13.8 ± 5.9%), coral rubble (1.5 ± 2.4%) sand (0.6 ± 0.7%) and others (0.2 ± 0.4%) were represented as non-living components. Two dominant coral species were identified as Pocillopora damicornis and Montipora aequituberculata, their percentage values from the total coral cover were 28.8 ± 14.2% and 24.6 ± 9.6% respectively. Other living corals were represented as 11.3 ± 5.4%. Algae cover also consists of several fleshy and filamentous Algae types (Caulerpa racemosa, Halimeda sp. and Chaetomorpha sp, Padina sp, Crustose coralline algae). In addition to corals and algae, giant clams (Family: Cardiidae, Tridacna sp) and typical coral reef fish (herbivore 59.1 ± 11% [sergant fish 41.2 ± 14%, damsel fish 27.3 ± 2.5%], carnivore 34.2 ± 4.4%, and omnivore 6.7 ± 5.2%) were also present associated to coral in Paraviwella. Other invertebrates such as Sea cucumbers (Order Elasipodida, family Pelagothuriidae), Sea Urchins (Order: Echinoida). The present water quality, the living and non –living benthic composition suggest that the Paraviwella reef could be used as a natural mesocosm for experiments.

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Conference Presentations by Shiran Chamika

Coral reefs have suffered from a range of impacts from local anthropogenic influence to global cl... more Coral reefs have suffered from a range of impacts from local anthropogenic influence to global climate change. These changes adversely affected to switch coral dominated reefs systems to algae dominated systems. However the mechanisms related to these global changes in coral reefs is not well understood to date. We hypothesis that microbial activity in reef waters could be a possible lower scale indication to explain mechanisms related to global change in coral reefs. Reef benthic monitoring, water chemistry (Dissolved Organic Carbon-DOC) and higher Dissolved Inorganic Nitrogen-DIN) and abundance of microorganisms (Bacteria and Virus) performed 08 coral reef sites around Sri Lanka from February 2014 to April 2015. Results show that the coral reefs in north are dominated by living corals whereas reefs in south dominated by algae. Algal dominant reefs represented by higher microbial abundances with relation to lower concentrations of DOC and higher DIN. These results suggest that potential connectivity to changes of reef systems with the microbial activity. Further analyses are in progress to explain how microbes structuring reef in Sri Lanka

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This presentation won the best oral presentation award at the International Indian Ocean Symposiu... more This presentation won the best oral presentation award at the International Indian Ocean Symposium held on 30th Nov- 4th Dec 2015 at Goa, India.

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Thesis Chapters by Shiran Chamika

Mariculture is one of the newly emerging aquaculture systems in Sri Lanka that have the potential... more Mariculture is one of the newly emerging aquaculture systems in Sri Lanka that have the potential to contribute significantly to the economic development. Oceanpick Private Limited a joint venture with Kames Fish Farming Limited is the first ever commercial scale mariculture farm in Sri Lankan waters which farm Barramundi (Lates calcarifer) according to the sustainable eco friendly principles. Nursery phase is an important part of the Barramundi production cycle that follows good husbandry practices and animal welfare. Therefore got trained the Barramundi nursery practices and management process at Oceanpick barramundi nursery in Trincomalee from 23rd of February 2015 to 23rd of May 2015. Developing the managerial skills, attitude and interpersonal skills, industrial application of theoretical knowledge and understanding and familiarization to the science and the art of handling an aquaculture venture were the objectives of that training. In this report I have attempted to provide a brief but thorough description of the knowledge gathered, skills acquired and situations experienced. The content of five chapters to follow in this report is based on my experiences and was compiled by myself. The first chapter is dedicated to make an introduction with a literature base while the second chapter describes the Oceanpick Barramundi nursery at a glance. A considerable period of time was allocated to study the design and function of the nursery system and also got training in nursery practice. In addition to that emergency case management and solution developing was experienced. Those experiences are presented in chapter three and four. The final chapter (chapter 5) discusses the lessons learnt throughout the training period and also it gives my suggestions with future perspectives to the Oceanpick (Pvt) Ltd Barramundi nursery.

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Papers by Shiran Chamika

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Wayamba University of Sri Lanka. Kuliyapitiya, 2014

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Food Control

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Food Chemistry

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Coral reefs have suffered from a range of impacts from local anthropogenic influence to global cl... more Coral reefs have suffered from a range of impacts from local anthropogenic influence to global climate change. These changes adversely affected to switch coral dominated reefs systems to algae dominated systems. However the mechanisms related to these global changes in coral reefs is not well understood to date. We hypothesis that microbial activity in reef waters could be a possible lower scale indication to explain mechanisms related to global change in coral reefs. Reef benthic monitoring, water chemistry (Dissolved Organic Carbon-DOC) and higher Dissolved Inorganic Nitrogen-DIN) and abundance of microorganisms (Bacteria and Virus) performed 08 coral reef sites around Sri Lanka from February 2014 to April 2015. Results show that the coral reefs in north are dominated by living corals whereas reefs in south dominated by algae. Algal dominant reefs represented by higher microbial abundances with relation to lower concentrations of DOC and higher DIN. These results suggest that potential connectivity to changes of reef systems with the microbial activity. Further analyses are in progress to explain how microbes structuring reef in Sri Lanka

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Wayamba University of Sri Lanka. Kuliyapitiya, 2014

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Food Control

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Food Chemistry

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BackgroundGenomic research allows new discoveries to alleviate human suffering but in turn raises... more BackgroundGenomic research allows new discoveries to alleviate human suffering but in turn raises significant ethical issues. In this context, public acceptance and engagement is a major determinant of optimization of genomic research. Therefore, understanding public perspectives related to genomic research is imperative, as it provides a foundation to address ethical issues which may be unknown to researchers and other stakeholders. Although genomic medicine and research has developed in Sri Lanka during the past decade, there is a paucity of understanding about public knowledge and attitudes towards it. MethodsThis research, therefore, aims to explore the understanding, knowledge and attitudes of a Sri Lankan public towards genomic medicine and research, in order to consider more effective and appropriate ways of communicating about the risks and benefits of participating in genomic research. Twenty four participants will be purposively selected from a previously conducted Colombo...

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Coral reef have suffered from a range of impacts from local anthropogenic influence to global cli... more Coral reef have suffered from a range of impacts from local anthropogenic influence to global climate change. These changes adversely affected to switch coral dominated reefs systems to algae dominated systems. However the mechanisms related to these global changes in coral reefs is not well understood to date. We hypothesis that microbial activity in reef waters could be a possible lower scale indication to explain mechanisms related to global change in coral reefs. Within this hypothesis Pigeon Island Coral Reef in Sri Lanka was subjected to benthic monitoring, water chemistry (Dissolved Organic Carbon [DOC] and higher Dissolved Inorganic Nitrogen [DIN]) and abundance of microorganisms (Bacteria and Virus) in April 2015 to determine the status of microbial activity. Results shows that the percentage live coral cover was relatively high (higher than 60 %) and the percentage algae cover was relatively low (less than 8%). Microbial abundance was in the range similar to the coral dominated reefs with low algae cover with relation to the DOC (70+12uMC) and DIN (2± 0.6mM) concentrations. The global comparison confirmed the results from this study fit with the DDAM model (DOC, Coral Disease, Algae and Microbes) to explain coral reef microbialization.

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