Rameswaram Island Research Articles

Cutaneous Fibroma in Largescale Mullet, Planiliza Macrolepis (Smith, 1846) from Rameswaram Island, Southeast India

Cutaneous Fibroma in Largescale Mullet, Planiliza Macrolepis (Smith, 1846) from Rameswaram Island, Southeast India

A High-Resolution Digital Bathymetric Elevation Model Derived from ICESat-2 for Adam’s Bridge

This data descriptor elaborates the details of a high-resolution digital bathymetric elevation model generated for the region, namely, Adam’s Bridge, which encompasses a chain of shoals between Rameswaram Island, off the southeastern coast of Tamil Nadu, India, and Mannar Island, off the northwestern coast of Sri Lanka. The proposed dataset has taken advantage of the photon penetrability in the shallow waters by the green laser of ICESat-2 LiDAR to derive the seabed topography. Seafloor depths from ~0.2 million geolocated photons of ICESat-2 for the study area were accrued and interpolated to generate a 10 m digital bathymetric elevation model. Adam’s Bridge, an isthmus and submerged reefal assemblage in shallow and super-shallow waters, is a feature of scientific curiosity. Our dataset has the potential to enhance the understanding of Adam’s Bridge structure by providing substantial information to reconstruct its evolution.

The Chemical Composition of some Waters from Slacks in Rameswaram Island, Madras State

Analyses of pH, total dissolved solids, CO,, HCO3, Cl, SO4, Ca, Mg, Na and K are presented for water samples from dune slacks in Rameswaram Island. Comparison of these analyses has been attempted with well waters from the area, sea water and world average fresh water. It is inferred that these slacks are under the influence of sea water but ion-exchange process similar to those in arid alkali soils appear to be responsible for Ca/HCO3 ratios of less than unity and Na/Cl and Mg/Cl ratios greater than those in sea water. Exceptionally high Na2Co3 and NaHCO3, contents in one of the slack waters is explained on the basis of sulphate reduction due to favourable conditions developed locally there.

Morphological Deformities in Stingrays (Dasyatidae) from the Rameswaram Island, South India

The present study reports the deformities in two different species of stingrays Maculabatis bineeshi and Neotrygon kuhlii along the Rameswaram Island. The structural deformity was observed in M. bineeshi species that were collected from Pamban–Therkuvadi fish landing centre, which was the first to be recorded along the Indian coasts with rostral irregularity of the aperture from the anterior margin of the snout around the right margin of the disc from the first gill opening. In addition to the first record, vertebral column deformity was observed in N. kuhlii, which was collected from Kunthukal fish landing centre. The external morphological characteristics showed a curved tail that had vertebral column deformities with severe scoliosis–kyphosis–lordosis starting from the pectoral girdle to the tail region

Morphological Deformities in Stingrays (Dasyatidae) from the Rameswaram Island, South India

Morphological Deformities in Stingrays (Dasyatidae) from the Rameswaram Island, South India

Habitats of House Sparrow Passer domesticus (Linnaeus, 1758) in Rameswaram Island, Tamil Nadu, India

This paper pertains to the nesting habitats of House Sparrow Passer domesticus with specific reference to population dynamics, nesting-related habits, nests, behaviours and other threats faced by these birds in Rameswaram Island. A total of 2,988 adult House Sparrows and 407 active nests were counted during the study. Of nests counted, 19% (n = 77) were solitary. The highest number of nests observed in a cluster was 9 (2 clusters). 60% of nests (n = 244) were found in concrete buildings, 39% (n = 159) in artificial nest-boxes, and 35% (n = 144) in cavities/crevices within buildings. House Sparrow population exhibited nesting plasticity, and 2% of nests were found constructed on vegetation. A wide variety of locally available materials, such as pieces of synthetic fishing nets, nylon ropes, and polythene papers were used for construction of nests. Sand and water bathing by birds were observed. Accidental fall of eggs and chicks, predation of nests by House Crows Corvus splendens, and unsuccessful attempts to predate adult birds by Black Kite Milvus migrans were observed, as well as opportunistic sightings of Shikra Accipiter badius.

Carbonate landforms of Rameswaram Island, Tamil Nadu coast, India: a review

Carbonate landforms of Rameswaram Island, Tamil Nadu coast, India: a review

First Asian record of Light-mantled Albatross Phoebetria palpebrata (Foster, 1785) from Rameswaram Island, Tamil Nadu, India

This document is a first sighting record of the Light-mantled Albatross Pheobetria palpebrate from Rameswaram island in Southern India. This is an unusual record from the region as it has not previously been recorded from either South Asia or the Oriental region.

Uncommon Mass Beaching of Porpita porpita (Linnaeus, 1758) in the Gulf of Mannar, Tamil Nadu, India

Porpita porpita (Linnaeus, 1758) was found stranded on the beaches from Vadakadu to Olaikuda Coastline, Rameswaram Island, Gulf of Mannar, after the Nivar Cyclone hit from December 7 to 14, 2020. The current mass beach stranding of P. porpita can be explained by offshore swarming and subsequent drift away to the beach due to shoreward water currents and wind speed.

Occurrence and characteristics of microplastics in the coral reef, sea grass and near shore habitats of Rameswaram Island, India

This study compares the occurrence and characteristics of microplastics (MPs) and heavy metal contaminants in the water and sediment of three habitats (corals, seagrass-beds and near-shores) of Rameswaram Island, India. The overall mean concentration of MPs varies from 24 ± 9 to 96 ± 57 items/L in water, and from 55 ± 21 to 259 ± 88 items/kg in sediment. The value of abundance is the greatest in the coral reef site CR-1 (96 ± 51 items/L; 259 ± 88 items/kg) followed by the seagrass site SG-2 (94 ± 55 items/L; 203 ± 75 items/kg) and the near-shore site St-15 (95 ± 63 items/L; 193 ± 75 items/kg). PE fiber (<1000 μm) is predominant in water, whereas PP fiber and fragment (between 2000 and 5000 μm) dominate the sediment. The SEM images of MPs reveal features which are characteristic of degradation like surface roughness, cracks, protrusions, and chalking, along with surface precipitates of both chemical and biological origin. EDAX images show the presence of Cr, Fe, Hg, Pb, Cu, As and Cd associated with MP surfaces.

Tracking Decadal Changes in Palk Bay Coral Community Structure: A Multivariate Approach

The study assessed a decade long changes of the coral community structure in the Palk Bay region using multivariate analysis based on observed coral life-forms and its diversity between the years, 2002 and 2018. A total of 11 study sites were selected from Rameswaram Island to Mandapam coast. Live coral cover was found to be 27% (21% non-Acropora and 6% Acropora corals) during the study period 2002–2005. Principal component analysis (PCA) showed that there was a significant variability (PC1: 39.5% variance) in coral cover between the study site, Bison House and the rest of the study sites. In the study of 2014–2018, live coral cover observed was 17% and this included 11% non-Acropora and 6% Acropora corals. PCA showed that the contribution of live coral cover gradually reduced towards the northern part of Rameswaram Island. Metric multi-dimensional Scaling (MDS) showed that there were four clusters formed between the sites with 80% similarity as observed based on the life-form categories. There were three major clusters with 70% similarity observed based on coral diversity. The highest diversity index (Shannon-wiener) was observed at Olaikudah and Villunditheertham as 1.906 and 1.864 respectively. As of 2014–2018, the live coral status showed 37% less than that found during 2002–2005 study period. Variation of reef flat composition was studied using Depth-Invariant Index for the study period 2002–2005. This study has helped to understand the longitudinal gradient of incidence, temporal variations, and distribution pattern of coral reef community categories in the Palk Bay region.

Assessing the Rate of Shoreline Changes of Rameswaram Island, Tamilnadu, India, using MATLAB Component Runtime Utility &amp; Digital Shoreline Analysis System

The Present study highlights the changes in the coastal tract of Rameswaram island located between the geometric location, latitude 9° 10' to 9° 20' N and the longitude 79° 12' to 79° 30' E. Using Geospatial Technology, Long-term changes have noticed from digitized shorelines taken from Landsat imageries and SOI toposheet for the years 1968, 1978, 1988, 1999, 2009 and 2018. Digital Shoreline Analysis System (DSAS) an extension provided by USGS for ArcGIS used to cast transects perpendicular from the baseline, towards the shorelines. High water Line (HTL) has taken as shoreline in this study. The distance between the shorelines has taken from the cast transects plotted from the baseline. For the rate of change calculation, MATLAB component runtime utility for ArcGIS has used. Based on the Linear Regression Rate (LRR) the shore has classified into High Erosion, Low Erosion, Stable and Low Accretion, High Accretion zones. The island has a shoreline length of 78.4 km, and the studies found that 27.83 km (35.41%) of shoreline is accreting nature, 37.90 km (48.21%) of shoreline is stable, and 12.86 km (16.36 %) of shoreline tends to erode. During the field investigation identified that High amount of erosion occurred in the locations near Pamban, Tharavaithopu and Dhanushkodi. Also, Accretion identified over the locations Ayyanthopu, Natarajapuram and Arichumanai tip. Wind action is one of the physical parameters that induced the erosion in some location of this study area.

Two new host records of the cymothoid isopods from Rameswaram Island, southeast coast of India.

Cymothoid isopods are parasitic crustaceans that are considered as a potential threat to the health of different fish species, which eventually lead to economic loss to the fisherman's society. For the first time, cymothoid isopods Nerocila sundaica and Nerocila poruvae infested on the two new host fish species viz., Eleutheronema tetradactylum and Setipinna taty, which were collected from Rameswaram Island, Southeast coast of India. Being an ectoparasite, N. sundaica was found attached on the gill chamber of E. tetradactylum, while N. poruvae was attached on the body surface of S. taty. The standard length 10-250 cm body mass was established for the new host species, and the parasitologic indexes were calculated.

Developing GIS based Coastal Water Quality Index for Rameswaram Island, India positioned in Gulf of Mannar Marine Biosphere Reserve

This paper employs widely used Water Quality Index (WQI), which synthesizes biological and physiochemical parameters into one single number that can be straightforwardly understood by decision makers and public. Rameswaram Island is one of the highly populated Islands of India, embraces with density of economically/ecologically important species and is most significantly located between Palk Bay and Gulf of Mannar. Water quality data obtained from 25 sampling sites around Rameshwaram Island between April 2011 and March 2012. The key parameters included for development of Water Quality Index were pH, temperature, turbidity, suspended solids, dissolved oxygen and biochemical oxygen demand using multiplicative water quality index. WQI lies in the “Good” category for all the seasons except summer, which falls under “Moderate”. Station 5B shows “Moderate” WQI in all the seasons because of the pilgrimage and tourism activities as well as the settlement at Rameswaram discharging municipal sewage. The use of the indices on a continuous basis provides long-term data which is helpful for decision making and management.

24 Tirtha’s of Ramanatha Swamy Temple, Rameswaram

We know Ramayana and Ramesawaram, the memorable temple located at the tip of Indian Point in Tamil Nadu. It is the most important visit in the Hindu Religion and through the year tourist multitude the place to take a bath in the famous “Tirthams” of Rameswaram. Ramanathaswamy Temple is a Hindu temple enthusiastic to the god Shiva located on Rameswaram island in the state of Tamil Nadu, India. Rameswaram Temple Tirthas are the holy wells situated inside the Rameswaram Temple in Tamilnadu, India. There are sixty-four Tīrthas (holy water bodies) in and around the island of Rameswaram. According to Skanda Purana, 24 Tirthas in Rameswaram are important and taking snan (bathing) in them are considered equivalent to penance. Twenty-TwoThirth as are inside Ramanatha Swami Temple.

Investigation of natural background radiation of sediments in Rameswaram Island, Tamil Nadu, India

The aim of the study is to assess the natural background radiation in and around Rameswaram Island. In this context, samples were collected to measure the gamma radiations of 238U, 232Th, and 40K using NaI(Tl) detector-based gamma ray spectrometer. The average activity concentrations of 238U, 232Th, and 40K are noted to be well below the world average values. The calculated absorbed dose rate, radium equivalent activity, and hazard index values were below the prescribed limit. The grain size of the sediment was analyzed following Trefethen’s nomenclature, and its correlation with the natural background radioactivity was studied. The sample that contained clay show elevated activity of 40K. The percentage of heavy minerals shows concomitant variation in natural radioactivity, especially in the activity of 238U and 232Th.

Macrodebris and microplastic distribution in the beaches of Rameswaram Coral Island, Gulf of Mannar, Southeast coast of India: A first report

This is the first study on the distribution and characteristics of plastic debris found in the sediments of Rameswaram Island, Gulf of Mannar, India. Studies on the distribution of plastics and microplastic content in highly populated coral islands and their impact on the coral ecosystem are very scarce. For this purpose, marine sediment samples were collected from 20 locations along the coastal areas of the study region. The distribution and characterization study was carried out by visual examination followed by FTIR spectroscopy. The results showed abundance of white-colored and irregular-shaped plastic debris in this study area. Polypropylene was identified as a dominant polymer variety, followed by polyethylene, polystyrene, nylon, and polyvinyl chloride. Tourist activities and fishing practices were found to be the possible sources of the microplastic debris. Additionally, the distribution of the plastics was found to be dominantly controlled by the aeolian process and the nature of the coast.

Spatial variation in the health of coral reef communities of Palk Bay, southeast coast of India

This study was conducted to assess the health of the coastal ecosystem based on bio-physical assessment of the coral reef ecosystem at Palk Bay. A total of 11 sites along the coast from the eastern part of Rameswaram Island to Mandapam were chosen for this study. Good live coral cover (acroporid and non-acroporid corals) of 30.08 ± 6.72% was recorded in the eastern part of Rameswaram Island. Principal component analysis demonstrated that the contribution of live coral cover was closer to the selected study sites of the eastern part of Rameswaram Island. Metric multi-dimensional scaling analysis showed three major clusters with 75% similarity based on life-form categories observed in the reef ecosystem. In this study, there was a significant segregation of study sites of the eastern part of Rameswaram Island in two clusters with 80% similarity because of their richness of live coral cover. Multi-dimensional scaling based on coral species diversity showed three major clusters with 50% similarity. Principal component analysis showed that the major contribution and abundance of coral species were closer to the northern part of Rameswaram Island. Moreover, Shannon–Wiener species diversity index of this region was in the range of 1.592–1.856, which was higher than the other sites. Hence, it was observed that there is no relationship between mean live coral cover and coral species diversity index of the reef ecosystem. The impact of biological indicators such as Halimeda algae and Palythoa sp. (Zoanthids) on the reef ecosystem was also analyzed. About 31 species of live corals belonging to 9 families and 18 genera were recorded during the study period. The outcome of this study helped in the understanding of the health of the ecosystem based on the intensity of mean live coral cover and coral species diversity. It also made it easier to understand the longitudinal variations and distribution pattern of coral reef community categories.

Spatio-temporal variability of hydro-chemical characteristics of coastal waters of Gulf of Mannar Marine Biosphere Reserve (GoMMBR), South India

The intention of this study was to appraise the spatial and temporal variations in the physico-chemical parameters of coastal waters of Rameswaram Island, Gulf of Mannar Marine Biosphere Reserve, south India, using multivariate statistical techniques, such as cluster analysis, factor analysis and principal component analysis. Spatio-temporal variations among the physico-chemical parameters are observed in the coastal waters of Gulf of Mannar, especially during northeast and post monsoon seasons. It is inferred that the high loadings of pH, temperature, suspended particulate matter, salinity, dissolved oxygen, biochemical oxygen demand, chlorophyll a, nutrient species of nitrogen and phosphorus strongly determine the discrimination of coastal water quality. Results highlight the important role of monsoonal variations to determine the coastal water quality around Rameswaram Island.

Experimental farming of Kappaphycus alvarezii (Doty) Doty with income estimates at different sites in the Mandapam region, Palk Bay, southeast coast of India

The cultivation of Kappaphycus alvarezii, a kappa carrageenan producing red seaweed, was done for 1 year from April 2012 to March 2013 in subtropical waters of Indian Peninsula at three different sites (Mangadu in Rameswaram Island, Munaikadu and Vedalai—on main land coast) on Palk Bay side of Bay of Bengal of Rameswaram–Mandapam region of southeast coast of India. These experiments were carried out to confirm the results obtained in an earlier study (April 2011 to March 2012) at more or less the same sites—one is different (Mangadu) and two are the same (Munaikadu and Vedalai). The maximum crop yields of 326.55 ± 10.23 and 316.65 ± 15.13 kg FW raft−1 were obtained in October 2012 at Mangadu and Munaikadu, respectively, and 308.40 ± 8.89 kg FW raft−1 in March 2013 at Vedalai. Similarly the maximum daily growth rates (DGRs) of 3.76 ± 0.07 and 3.69 ± 0.11 % were found in October 2012 at Mangadu and Munaikadu, and 3.64 ± 0.06 % was obtained in March 2013 at Vedalai. A significant negative correlation between DGR and seawater temperature at Mangadu (r = −0.604) and Munaikadu (r = −0.700) was found (at 0.05 level). Further, a significant positive correlation was seen (at 0.05 level) between nitrite and phosphate at Mangadu (r = +0.613) and Vedalai (r = +0.599). However, salinity and seawater temperature were significantly positively correlated (r = +0.693) at Munaikadu (at 0.05 level). ANOVA showed that the growth rates among these three sites were found to be statistically insignificant. Tip grazing by Siganus javus and Diodon holocanthus during the monsoon period (October 2012 to January 2013) was observed. Seasonal epiphytes Lyngbya majuscula and Cladophora facsicularis were the main problematic epiphytes from April to June. Net income would be Rs15,000 to Rs16,000 (US$250–US$265) per month, and if the cultivation is taken up in earnest perspective, the farmers would improve their living standards.