Browsing by Author "Sivakumar, K."

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An Investigation of the Relationship Between Green Turtle (Chelonia mydas herbibory and Seagrass in the Agtti Lagoon, Lakshadweep
(Wildlife Institute of India, Dehradun, 2007) Lal, Aparna; Choudhury, B.C.; Sivakumar, K.
Globally, nearshore ecosystems are being increasingly impacted upon by expanding coastal development. The almost complete dependence of marine mega herbivores like Green Turtles (Chelonia mydas) on these habitats for food together with their current low population levels in many regions highlights the need to understand this vital relationship. This study was an attempt within this framework. It aimed to quantify the intensity and potential impacts of Green Turtle grazing on the seagrass Cymodocea rotundata in the Agatti Lagoon, Lakshadweep. To map the habitat types in the lagoon, points generated from a grid were used, while 23 transects, perpendicular to the shore, formed the basic sampling unit to assess turtle density and map their distribution patterns across the lagoon. The study recorded exceptionally high turtle abundances within the lagoon with their distribution patterns being restricted to certain areas within the seagrass meadow. The magnitude and potential impacts of herbivory were quantified across the established gradient of turtle density in the lagoon. It was found that C. rotundata plant parameters like morphology, life history strategies, population dynamics and meadow level characteristics were significantly different in areas with less turtles, indicative of a response to turtle grazing, results supported by experimental evidence. It was found that increased shoot recruitment rather than increased shoot production could be a mechanism whereby seagrass deals with intense herbivory. This study shows that grazing intensity is an important factor potentially regulating the response of seagrasses to grazing.
Avian Responses to Varying Landscape Parameters in Mangrove Forests of Coastal Gujarat
(Wildlife Institute of India, Dehradun, 2015) Kulkadia, Devanshi; Talukdar, G.; Gopi, G.V.; Sivakumar, K.
Mangrove systems are the most productive ecosystems on the earth. The mangrove environment provides living space for dependent biota of more than two thousand species of flora and fauna of resident, semi-resident or migratory wildlife. The conversion of large contiguous tracts of the tropical mangrove forests to smaller patches embedded in a landscape matrix surrounded by human-altered habitats is one of the most serious concerns as it would affect their associated species such as birds, fishes, etc. In this context, this study was carried out aiming at discerning the responses shown by avifauna to varying landscape parameters like the mangrove patch characteristics, the level of disturbance and the structure of mangrove vegetation. Therefore, the abundance and diversity of the avifauna in mangrove forests at twenty selected sites on the coasts of Gujarat were investigated using point count surveys for a period of five months (December 2014-April2015). 2. A total of 98 points were laid across the twenty patches o(mangroves and surveyed twice during winter and summer seasons, respectively. Data were collected from the four replicates of each point during the entire study period. The total area surveyed during the study at these twenty mangrove patches was 47.97sq.km. These patches were ranging from various size classes with the smallest patch of the size of 0.125sq.km to the largest patch size was of 10.49 sq.km and were distributed throughout the coastline of 1650 km long. Habitat correlates such as structural and floristic characteristics of mangroves were quantified for each patch to establish their relationship with avifaunal abundances. 3. Despite recording only 7 species of mangroves in the twenty patches, a wide variety of birds totaling to 119 species were recorded from the mangroves during the two seasons, i.e. winter and summer during the study. 4. From the data collected by the variable-width point counts, the mean density of birds from the patches were calculated to be 6.485/ha in winter and 4.898/ha in summer. The diversity of birds varied across the seasons. A total of 104 species of birds were recorded during the summer season as compared to 117 species of birds in winter season. 5. Large contiguous patches of mangroves were found to be supporting fewer species of birds than the smaller patches. The avian species richness of the smaller fragments were largely governed by the adjoining environment settings (matrix) of the patch. Therefore, the study found that the diversity of the birds was not found to be getting influenced by the area of the patch as the species richness was found to be increasing with the number of the surrounding matrix. 6. It was found that the structural composition of mangroves especially the canopy cover was found influence the bird density and diversity greatly as with the increase in the canopy cover, the bird species diversity and density also increased in a patch. 7. The bird assemblages in the mangroves showed a significant response towards the disturbance. The disturbed patches contained an overlapping mixed composition of the forest birds and open country birds in an equal proportion, whereas the undisturbed patches showed less number of open country birds. 8. Based on the study, it is suggested that the larger sized mangroves patches are important for their ineffable ecological services, therefore, these patches should be protected and conserved. Similarly, the smaller and fragment of mangroves patches are also equally important as they hold a good number of avifauna! species and hence, we have to adopt some strategies to conserve all the remaining – large contiguous and small fragmented patches of the mangroves from further degradation.
Conservation status of fishes in the tributaries of Ramganga with special reference to golden mahseer Tor putitora Hamillton
(Wildlife Institute of India, Dehradun, 2005) Atkore, Vidyadhar Mahadeorao; Sivakumar, K.; Johnsingh, A.J.T.
A common goal in the studies of community ecology is to uncover patterns of species abundance or distribution and determining the factors that are responsible for them. Himalayan waters are unique in the ichthyofaunal diversity. To know what species are here, fish sampling was carried out with help of cast net. Three rivers were identified for the stratified fish sampling. Each river was divided at two hundred meter distance apart. Each segment was sampled thrice though out study period. Morphometric measurements were taken in the field. Habitat parameters were also recorded as on same day of fish sampling. Result shows that MandaI River had .more species richness followed by Khoh and Kolhu. Forty three species belonging to five orders and ten families (four species yet to identify) were recorded in the study river. Of these, approximately 80 % were classified into the rare category. Tor putitora, Garra gotyla Barilius barila, and Scizothorax richardson are listed in the IUCN Red list. However, endangered golden mahseer was one of the commonest fish. The reason could be the preferred spawning habitat ground or abundant food availability. Population estimation was estimated by using Jolly Seber method, resulted high standard error. Low number of recapture sessions could be the reason. Mostly juveniles of 6-10 cm size classes were abundant in all three rivers followed by 11-15 cm group. The total length measured for Golden mahseer varies from 3 cm to 28 cm. The condition factor was calculated based on the available size class. Result showed that 20-25 cm size classes of golden mahseer were in better condition in the Study Rivers. However, condition for size class 0-5 cm fish was better in Kolhu River than others. The 6-10 cm size class, 15-20 cm and 21-25 cm were doing better in the MandaI than two rivers.
Ecological responses of Intertidal Benthic communities to certain abiotic factors in Nancowry islands, Nicobar
(Wildlife Institute of India, Dehradun, 2017) Kandregula, Samyukta Rao; Sivakumar, K.; Johnson, J.A.
The intertidal zone is the amphibious niche between the high and low tides. The invertebrate taxa present here lay bare to several influencing factors and facilitate the flow of energy by participating at each trophic level in the marine ecosystem. This study was carried out in order to assess the community structure of intertidal benthic macro invertebrates. Their associations with various factors known to affect intertidal zones were looked into, in the remote islands of Kamorta and Nancowry in Central Nicobar, Andaman and Nicobar archipelago. Three study sites of varying beach profiles (reflective, intermediate and dissipative) were studied across spatio-temporal scales. Baseline information was drawn 'on the key players of the macrofauna community signals. Replicates need to be studied to confirm the patterns observed. Comprehensive community level analyses (at species) need to be done along with supplementary data through Total Organic Carbon (TOC) analysis and heavy metal analysis (ICP-MS analysis) needs to be done to ascertain the sources and magnitudes of the signals of influencing factors.
Ecology and conservation of Ichthyofauna in the Godavari River Restuarine Ecosystem (EGREE) Andhra Pradesh
(Wildlife Institute of India, Dehradun, 2022) Paromita Ray; Johnson, J.A.; Sivakumar, K.
This study was conducted to understand the ecological processes and functions of the estuary, including studying the role of the Godavari mangroves as fish habitats, is needed to maintain the various ecosystem services of EGREE. The three main objectives of this thesis are: 1. To study the spatio-temporal changes in fish assemblage across the different habitats in East Godavari Riverine Estuary Ecosystem (EGREE) 2. To study the trophic ecology of ichthyofauna in East Godavari Riverine Estuary Ecosystem (EGREE). 3. To study the role of mangrove forests in structuring the ichthyofauna in Coringa Wildlife Sanctuary. This study was conducted between June 2014 and May 2017 in the estuarine zone of the Godavari delta and the mangroves of Coringa Wildlife Sanctuary in Andhra Pradesh.
Ecology and Migratory patterns of the Golden Mahseer, Top Putitora (Hamilton,1822), in Western Himalayas using Radio Telemetry Techniques
(Wildlife Institute of India, Dehradun, 2023) Dhawan, Bhawana; Johnson, J.A.; Sivakumar, K.
This work is one of the most important and iconic freshwater fish species, golden mahseer Tor putitora (Hamilton, 1822), that provides crucial insights into the assemblage structure, food and space resource of the species, habitat ecology, life-history characteristics and movement ecology of the species. This study is the detailed study of any freshwater fish species in which movement patterns in the streams have been studied using radio telemetry techniques in the Himalayan streams.
Ecology of Seagrass Habitats and its associated macrobenthic invertebrates in Andaman islands, India
(Wildlife Institute of India, Dehradun, 2024) Gole, Swapnali; Sivakumar, K.; Johnson, J.A.; Das, Himansu
The diversity, composition, and growth of species in plant communities are shaped mainly by their complex interactions with local environmental settings. Owing to the unprecedented global decline of seagrasses, it is crucial to understand in-situ ecological interactions for informing mitigation measures. However, several ecological aspects of seagrass ecosystems are under-studied in the tropical Indian waters, which fall in the highly productive Indo-Pacific seagrass distribution bioregion, offering many socio-ecological services. In this context, my study aimed to address the ecological gaps in India's unique seagrass biodiversity hotspot, the insular archipelago called the Andaman and Nicobar Islands (ANI). Objectives of the study were 1) To assess the spatial distribution patterns of seagrass habitats and associated macrobenthic invertebrates in the Andaman Islands, 2) To understand the seasonal variation in seagrass meadows and associated macrobenthic invertebrates, 3) To understand the structural diversity of seagrass meadows and its influence on associated macrobenthic invertebrates, and 4) To document the Traditional Ecological Knowledge on seagrass habitats. The field study was carried out between 2018 and 2022, with a significant sampling period between January and May, as it is the best feasible season for fieldwork in ANI. The spatial diversity, distribution, and growth of seagrasses in the present study were primarily governed by the water depth, habitat heterogeneity, substrate types, and availability. The study suggests that any alterations in the benthic habitat profile of these meadows are likely to affect the species distribution patterns and overall ecological services offered
Evaluating the Impact of Introduced Spotted Deer (Axis axis) on Forest Floor Herpetofauna of Andaman Islands
(Wildlife Institute of India, Dehradun, 2013) Mohnty, Nitya Prakash; Vasudevan, K.; Sivakumar, K.
It is common knowledge that organism in an ecosystem, are connected to each other through trophic levels. Even though the importance of interactions among trophic levels is well established in theory, demonstration of such interactions is not always easy. Over the years, studies that focus on the trophic interactions among starkly different taxonomic groups have come to the fore. These studies have furthered our understanding of ecosystems by demonstrating relationships between trophic levels so apart, the connection among which may not be apparent at first. Along these lines, the situation of introduced spotted deer in the Andaman Islands presented an ideal opportunity to understand the potential effect of a mammalian invasive herbivore on native, insectivorous forest floor herpetofauna. I hypothesised that herbivory is likely to depress folivorous arthropod abundance, which in turn may lead to a decline of insectivorous forest floor herpetofauna. Additionally, reduction in vegetation cover may render the habitat unsuitable for herpetofauna and make them vulnerable to predation. The objectives of this study were to evaluate the effect of chital on the forest floor herpetofaunal abundance and to determine the pathway of interaction between them. A contrasting effect of herbivory by chital on reptiles and on amphibians in the Andaman Islands was observed during the dry season. Forest floor reptiles, which included agamids, geckos and skinks showed reduced abundance in the presence of chital in comparison to an island where chital was absent. This effect of chital on reptiles was found to be mediated by vegetation cover. Chital significantly reduced the vegetation cover below their maximum browse height (1.5 m) in the Islands and which in turn led to a reduction in reptile abundance. Although, it was not clear if any of the observed species was benefitted in the presence of chital, the semi-arboreal Coryphophylax subcristatus appeared to be affected. Amphibian abundance on the other hand seemed to be unaffected by the use of the habitat by chital. Litter arthropods influenced the densities of amphibians the most. This study brought to light a pathway of indirect interaction between a mammalian herbivore and insectivorous herpetofauna. In doing so it raised conservation concern about the capability of an introduced species to alter an island ecosystem drastically and acutely impact several endemic fauna.
Nest Site Selection and Effects of Anthropogenic Changes to the Rushikulya Nesting Beah, Orissa on Olive Ridley Sea Turtes
(Wildlife Institute of India, Dehradun, 2009) Muralidharan, M.; Sivakumar, K.; Choudhury, B.C.
The Olive Ridley sea turtle Lepidochelys olivacea is known to nest both sporadically and in arribada's in the Indian coastline. Of the three mass nesting sites on the Orissa coast, the Rushikulya rookery has been considered as a key factor in maintaining the future populations of the Ridley's in the Indian coast. Though several studies have been carried out on various ecological aspects of the species along the Orissa coast this study looked into a finer scale of behavioural patterns exhibited by the females while selecting the nesting sites. Other aspects that are looked into in detail in this study included the various impacts of anthropogenic activities near the nesting habitat of the turtles including the impact of nest predators. The observed sporadic nesting turtles crawled an average of 47.39 m from the waterline before nesting (Range = 10.7(102m, SD = 21.0481, n = 70). Tests were conducted to check for the possibility of whether turtles were actively choosing their site of oviposition while compared to random placement over varying distances. Beach slope and soil temperature were not found to be significantly different from the nesting sites (Slope - F = 1.289, . Temperature - F = 2.241, df = 8 P>0.05) while compared to sites along the track of the nesting turtles, whereas pH and moisture were found to be significantly different from the nest-site to all sites prior to them (pH - F=37.640, Moisture - F = 44.208, df = 8 P<0.05). This shows the possibility of both pH and slope to be amongst the possible proximate cues used by a turtle in deciding a final nest. The effects of beach lighting on the disorientation of turtle hatchlings at this site has already been studied at various levels and this study re-affirms the results of the previous studies by including the effects of lighting acting upon various distances away from the water-line as well as different photic conditions present along the beach and from the adjoining villages. With areas near the villages showing maximum disorientation while compared to areas shielded from light by Casuarina plantations. Associated human activities near the Rushikulya rookery could also act in supporting and maintaining populations of certain animals (feral dogs, jackals), which have had an increased threat to turtle nests. The plantation of Casuarina adjoining the nesting beaches could also act in providing refuge to such predators apart from the known effect of changing the geomorphologic profile of the beach. These predators are known to be able to thrive even in marginalized habitats sustaining their numbers near human occupied areas. These plantations may thus also be aiding an artificial boom in their numbers thus having an increased impact of their predation on turtle nest while compared to natural levels ·of predation loss. A Passive Tracking Index (PTI) for the predator presence and activity observed a minimum presence before the mass nesting which increased immediately after the commencement of the mass nesting. Protective chain link fencing laid across sections of the beach flanked by Casurina to reduce the predator pressure in these areas may not have proven to be completely successful as high activity was still observed in the weeks following the mass nesting.
Patterns in avian assemblages on two islands of the Central Nicobar with emphasis on interactions between the endemic Nicobar Bulbul and Red-whiskered bulbul
(Wildlife Institute of India, Dehradun, 2017) Goyal, Naman; Nair, Manoj V.; Singh, Pratap; Sivakumar, K.
Bird Communities were studied on two islands of the central Nicobar, namely Teressa (Large) and Bompuka (Small) between 16th December 2016 and 15thApril 2017. • This study aimed to understand the patterns in avian assemblages on these islandsand further understand the nature of interaction between Red-whiskered Bulbul and the Nicobar Bulbul • 4 major habitats were identified viz Primary forest, Secondary forest, Plantations, and Grassland based on an exhaustive reconnaissance survey • In total 110 point counts were conducted within these habitats on both the islands • 56 bird species belonging to 30 families were recorded during the study. Teressa had higher species richness than Bompuka • Bird assemblage on Bompuka was a complete subset of Teressa and nested ness was found to be significant (p
Patterns of foraging in Olive Ridley Sea Turtle (Lepidochelys olivacea) Population on the East Coast of India and Habitat Characteristics of the Arribada Nesting Ground at Rushikulya
(Wildlife Institute of India, Dehradun, 2019) Mudliar, Mohit; Sivakumar, K.; Gopi, G.V.; Shankar, Karthik
This study was conducted and aimed to explore the patterns of spatial segregation of foraging olive ridley turtles which nest on two distinct nesting areas of the eastern coast of India; secondly, to examine the characteristics of mass nesting ground of Rushikulya; and lastly, to assess the status of microplastic presence in mass nesting ground. The study found that the moisture contents and sand particle size were homogenous across the beaches of Rushikulya. The sandbar had most extreme values for four of the five studied habitat characters which might be due to surrounding waters. Sea turtles those stranded during December to February at Chennai as well as Rushikulya seems to be from a similar type of foraging areas as their carbon isotope ratio were not different
Pre and Post Covid-19 Transformation in the Financial and Marketing Practices of Museums: An Analysis of the Government Museum Chennai and City Palace Museum Udaipur.
(Wildlife Institute of India, Dehradun, 2021) Bhaalasaraswathi, J.; Sivakumar, K.
The research focuses on the effect of the pandemic on the museum. The two main areas of focus are marketing and finance management of the museums with the case study of the Government Museum Chennai and the City Palace Museum, Udaipur. All three museums are known for the antiquity of their collections, the history of the buildings which house these collections and the architecture of the building. The Government Museum, Chennai, is a museum run by the Government, while the City Palace Museum, Udaipur is a Non- profit Organisation run by a public charitable trust. The research will look at the marketing and the funding transformation in the museum because of the COVID-19 pandemic. The selection of Government Museum Chennai, the City Palace Museum Udaipur and Chhatrapati Shivaji Maharaj Vastu Sangrahalaya, Mumbai gives the research a comparison between museums that differ in ownership, funding and location. All the above-mentioned museums are multipurpose museums that exhibit artefacts and collections on various subjects.
Resource Selection and Conservation of Smooth coated otter Lutrogale perspicillata in and Around the Coringa Wildlife Sanctuary, Andhra Pradesh
(Wildlife Institute of India, Dehradun, 2015) Prasad, Nadendla Leela; Sivakumar, K.; Johnson, J.A.; Hussain, S.A.
Resource selection of Smooth-coated Otter Lutrogale perspicillata was studied in the Coringa Wildlife Sanctuary, where a two dimensional interface of fishermen-otter present: fishermen fishing in the habitat of otter and otters feeding in the aquaculture farms of fishermen. This is resulting in conflict between Otters and Humans in the region. In this context, this study was carried out to understand the extent of this conflict by studying the food habit of otters and ecological factors that could affect the otter distribution in this mangrove ecosystem. 2. The study was carried out from December 2014 to April 2015 in and around the Coringa Wildlife Sanctuary, which is located at the mouth of the Godavari River, in Andhra Pradesh. 3. Food habit of otters was studied by analysing their spraints that were collected from different parts of the Sanctuary. Habitat and distribution of otters were studied using belt transacts along creeks as otters mostly used banks of the creeks. Further, people perspectives towards otter and intensity of human-otter interface was studied using interview based questionnaire surveys. 4. It was found that the fishes cultured in the aquaculture farms were not present in the creeks of Coringa WLS. 6. The diet analysis of 81 spraints collected from December 2014 to March 2015 revealed that fish comprise of 99% of Smooth coated Otter diet. Of this major portion comprised of Mystus gulio, Oreochromis mossambicus and Liza tade. These species were also found in high abundance during the fish sampling from which relative abundance was calculated. This indicates that Otters in the sanctuary are opportunistic feeder rather than selective. 7. Mystus gulio (long whiskers catfish) found to be the major prey of otter in the Coringa . WLS, constituting 17.8% of weight of all food items found in the spraints and this fish was also eaten by many otters (found in 13.4% of spraints). M gulio was also the most common fishes of the Sanctuary. M gulio followed by Oreochromis mossambicus (Tilapia) constituting 14.6% of weight of all food items found in the spraints. 9. Although, all five major aquaculture species offish were found in the spraints of Otter but overall, the aqua farm fishes constituted only the 14.4% of weight of total foods items found in the spraints of otter. Of the total spraints collected, only 17.8% of spraints contained the aqua farm fishes and remaining 82.2 % otter spraints did not have. aqua farms fishes and these otters were seems to be eaten only the wild fishes. 10. The high abundance of invasive tilapia was found in the Ramannapalem creek, which is a less saline creeks adjoining with aqua farms and villages. This fish was the second most preferred diet of otters in the area. This fish breeds in the grasses that are at the banks of creeks. Breeding tilapia was a easier target for otters and therefore, otters were seen close to aqua farms. 11. The factors essential for Otter survival in were found to be more towards land and decrease with increasing distance from land. An ordinal regression model with sign intensity in three ranks revealed that the factors that are playa significant role in Otter distribution are distance from sea had a positive effect on Otter distribution (estimate = 0.403, Standard error =0.225 and P value= 0.073), Width of channel also had a positive effect to an extent (estimate =0.509, Standard error =0.273 and P value = 0.062). Depth of the creek had a negative effect (estimate= -0.624, Standard error = 0.322 and P value=O.053). 12. As the factors that are positively influencing Otter distribution are near villages Otters signs were also found highest in creeks near villages. Thus it was concluded that the presence of Otters mostly towards villages is probably due to presence of suitable habitat near villages rather than fish from aquaculture farms. 13. Fishermen's Traditional Ecological Knowledge of Otters in and around the Coringa Wildlife Sanctuary had also confirmed that otters largely feed in the wild but visit aqua farms occasionally for food or to play. Further, about 79% of people in the region felt that Otters visit their farms at night that confirms the nocturnal behaviour of Otters around human habitation, which is supported by previous studies 14. Further, most of fishermen (75%) believed that otters are high threat to aquaculture when compared to fishing cat and jackals. This is due to group hunting behaviours of otters, whereas fishing cats and jackals visit aquaculture ponds solitarily 15. Interestingly, nearly 11 % of fishermen felt that Otters have caused an income loss of 1-5% followed by 9% of respondents who claimed a loss of 10-30%. But, few farmers (2%) felt that Otters cause nearly 30-50% of loss, who were in the low income group and who can not offer even small loss in income. 16. Generalized Linear Model (GLM) with Poisson distribution revealed that both income and education of fishermen positively influenced their perspectives towards conservation importance of otters in the region. 17. Majority of fishermen (65%) believed that there was a decline in the sightings of otters and they have also believed that the population had been declined in the region. However, in contrast, about 13% of them felt that there was an increase in Otter population over years and most of these respondents who have also believed that high loss of income due to otters visits to their aqua farms. 18. Most of the aqua-farm owners admitted that they always scare and chase away otters when they visits their farms. Though only 11 % of them opted for killing does not mean that people have a positive attitude towards Otter. Boxplot analysis to understand the relationship between people's action towards visiting otters to their farms and their income and education, has revealed that the farm owners who had less income have tried to kill the visiting otters due to their poverty. 19. This study found that fishermen with poverty could not bear even the meagre loss caused by otters to them. Further, the study found that less educated people against the otters in the region. Therefore, additional livelihoods and awareness education to those poor fishermen need to be provided for the long term conservation of otters in the region. EGREE Foundation of Andhra Pradesh, a foundation established with support of GoI-UNDP-GEF Project to sustainably manage the Godavari estuarine has already initiated some programme in this regard but their programme should focus more on fishermen who are with low income 20. It is also proposed to have otter proof fencing for aquafarms especially those farms located along the Ramanapallam creeks. Developing eco- tourism in the sanctuary with the involvement of fishermen and small scale farm owners can also change their attitude towards otters.
Spatial mapping of important marine habitats of Malvan Coast for re-organization of boundary of the Malvan Marine Sanctuary
(Wildlife Institute of India, Dehradun, 2023) Shinde, N.; Bayana, S.; Sarkar, D.; Pande, A.; Sivakumar, K.; Talukdar, Gautam
Malvan Marine Sanctuary is a Marine Protected Area located in the Sindhudurg district of Maharashtra state. Known for its rich biodiversity, it is grappling with increasing anthropogenic pressure necessitating a comprehensive study to assess its habitats and threats. Management Effectiveness Evaluation (MEE) of 2017-2018 team had suggested for boundary reorganization to exclude areas of human intervention and to include important habitats and areas with high biodiversity for the better management of biodiversity off the coast of Malvan. The project has undertaken because high tourism zone are areas with high anthropogenic pressure within the core zone of the sanctuary. Coral reefs and its associated fish fauna were surveyed at nine sampling sites. The total hard coral cover was observed to be 28% while the seagrass cover was observed to be 3% in 21 sampling sites. 19 genera of corals were identified. Favites sp.was observed to be the most abundant (19.18%). Within the sanctuary, Seagrass patches were identified at five sampling sites namely King’s Garden 1, King’s Garden 2, King’s Garden 3, Dharan and Donor site. 122 species of fish belonging to 38 families were observed during underwater surveys. Fish-market surveys were conducted to study the species composition and size-class of fish species caught around the sanctuary. A total of 44 different fish species were observed during market surveys. Beach litter surveys were conducted to assess the anthropogenic stress along the Malvan coastline. Debris in the form of polythene was the major contributing litter type at all three sections of the beach. The rocky outcrops along the coast were observed to be roosting sites for avifaunal species namely, White-bellied Sea Eagles, Pigeons, Swiftlets, etc. Spatial prioritization of the marine habitats revealed potential PA’s include Kawda, 7 rocks, Lighthouse area, covering an area of 29.07 sq.km; conservation priority areas comprising Chiwla, and Sargassm covering a total area of 19.21 sq. km and King’s garden (3.534 sq km) as sensitive area. Strategies to conserve these areas for long term conservation. should be planned. Spatial mapping of important marine habitats of Malvan coast for re-organization of boundary of the Malvan Marine Sanctuary
Spatial modelling of critical dugong habitats (CDHs) in India
(Wildlife Institute of India, Dehradun, 2024) Seal, Sohom; Sivakumar, K.; Raman, Mani
In India, there is a scarcity of comprehensive data on dugong distribution and their habitat suitability, complicating the development of effective conservation strategies. Baseline data on priority areas for dugong conservation was provided by the Wildlife Institute of India back in 2012. Therefore, a temporal data gap exists for a re-evaluation study of CDHs through collating recent dugong occurrences and fishing pressure collected through primary surveys. Further, this study could fill the data gaps by employing advanced spatial modelling techniques and integrating primary and secondary data collected through multi-stakeholder involvement, thereby providing a robust understanding of recent and more accurate CDHs. The study focused on four key dugong ranges along the Indian coast: the Andaman and Nicobar Islands (ANI), Palk Bay and the Gulf of Mannar (PB-GoM) in Tamil Nadu, and the Gulf of Kutch (GoK) in Gujarat. These regions are recognised for their rich marine biodiversity and extensive seagrass meadows, which are critical for dugong survival. The ANI features relatively pristine marine environments, while PB-GoM and GoK are heavily impacted by fishing activities and coastal development, making them significant areas for conservation focus. The primary objectives of this study are: 1) To understand the distribution status of seagrass meadows in selected dugong habitats using in situ and remote sensing data, 2) Mapping the interface between dugong distribution and fisheries in selected dugong habitats, 3) Mapping the environmental governing factors that determine dugong distribution, and 4) Integrating environmental and habitat parameters in GIS platform to classify Critical Dugong Habitats (CDHs). The study employed a combination of in-situ surveys and remote sensing techniques to map seagrass meadows. Intertidal and subtidal surveys were conducted using the line-intercept transect method, and satellite imagery from Sentinel-2A and 2B was utilised for classification in the Google Earth Engine platform. The study highlights the challenges of mapping in turbid waters and identifies suitable classification algorithms curated for different water conditions for better mapping accuracy.
Species Assemblage and Differential Basking Habitat Use of Freshwater Turtles in a Gradient of Mahanadi Riverine Ecosystem, Orissa
(Wildlife Institute of India, Dehradun, 2009) Jani, Chandan; Choudhury, B.C.; Sivakumar, K.
Of the seven species of turtles recorded in the Mahanadi River, this study recorded five species of freshwater turtles between Satkosia Gorge Wildlife Sanctuary and Khakadi (Near Cuttack city) during November 2008 to April 2009. Of these five species, four were softshell turtles (Nilssonia gangeticus, Nilssonia hurum, Chura indica, Lissemys punctata) and one was hardshell (Pangshura tentoria). Relative abundance in terms of mean number of individuals sighted per kilometre was estimated. The results showed that Pangshura tentoria was most abundant and was recorded over all the sampling zones, followed by Nilssonia gangetic vs Nilssonia hurum and Chitra indica. The latter three were not distributed as commonly as the former. Lissemys punctata was not included in the report as the species never sighted during the sampling secession. However, the species was found to get captured in incidental fish catch during the study period. The low abundance of Chitra indica and Nilssonia hurum might be due to degradation of their habitats. These two species are known to refer undisturbed and wider river stretches which are diminishing in the Mahanadi River. The habitats of the river stretch between Satkosia Gorge Wildlife Sanctuary and Kakhadi varied significantly and thus, explaining the variation in the species richness as well as abundance. The major habitat variables, which have highly influenced the turtle abundance were river flow, river width and river bank characteristics. Highest abundance of species was found in the non-riparian flow zones and river stretches with rocky and sandy banks, where the habitat heterogeneity was greater. These two sampling zones also experienced the least anthropogenic pressures. Choice in habitat use for basking in turtles was also observed. The choice of the habitat varied between species. Nilssonia gangetic and Nilssonia hurum preferred areas which had greater river bank width with shallow water near the bank. Chitra indica preferred areas where both river depth and river width were higher whereas bank slope, river slope, ground cover, alternative basking substrate and immediate water depth was lower. Pangshura tentoria preferred areas with greater river and bank slope along with greater availability of alternative basking substrate and greater immediate water depth. On the other hand they also preferred the habitat more close to the river with lower bank width and moderate river depth and moderate river width. Major threats to turtles in the Mahanadi river (sampling zones) are due to anthropogenic pressure and habitat degradation. Some of the threats were found to be consistent over the sampling zones. The study shows that Pangshura tentoria was highly tolerant to all prevailing threats in the Mahanadi river but, Nilssonia hurum and Chitra indica were adversely affected by these threats all along the river. This study found that there was a negative correlation between the turtle abundance and presence of threats such as sand mining, pump house, fishing and pollution. Sand mining adversely affected the basking habitat of most of the turtle species. Pump houses were largely avoided by the turtles which may be due to the vibrations or noise created at these stations. Unintentional by-catch of turtles during fishing was also observed especially in the braided flow zones and inundated static flow zones of the Mahanadi river. Sand mining and fishing are identified as the major threats to the turtles in the Mahanadi river, which should be monitored and regulated. Sand mining should not be allowed during the breeding season of the turtles especially in the area of Non riperian flow zone and braided flow zone. These two sampling zones were identified as the Important Turtles Areas (ITAs) in the Mahanadi River. Alternate livelihood options should be identified and implemented in order to reduce people's dependency on fishing in this region. Nature education and awareness programme clearly addressing the reason for declining of turtles and their habitat in the Mahanadi river needs to be launched.
Study on ecology and migratory patterns of golden mahseer (Tor putitora) in river Ganga using radio telemetry techniques
(Wildlife Institute of India, Dehradun, 2021) Johnson, J.A.; Dhawan, B.; Sivakumar, K.
Golden Mahseer, Tor putitora is popularly known as ‘Himalayan mahseer’ and it is one of the largest freshwater fishes of India It occurs along the mid-hills stretch of Himalayan region including Shivaliks and part of Terai landscape. Over the years, the golden mahseer populations and their habitats have depleted due to various anthropogenic activities, hence, it is listed as an Endangered species in the IUCN Red List. Due to rapid hydro-power developments in the river valleys, habitats of golden mahseer have been fragmented, which in turn affects the ecology and spawning biology of golden mahseer. In order to, understand ecology, habitat use and movement pattern of golden mahseer, this project was proposed in 2017. The study was carried out in the two river systems of Western Himalaya: Kosi river in Ramnagar and Kolhu river in Kotdawar. To study the movement and migratory patterns of golden mahseer, 11 individuals were tagged with radio telemetry tags in the month of June (before onset of monsoon) to understand the migratory behaviour of tagged individuals. Manual tracking and monitoring were performed for all the tagged individuals to get location points and to generate movement data during the period from June-October, 2019. Correspondingly, information related to the fish habitat-type, depth, velocity, temperature and weather was collected. Simultaneously, habitat inventory was performed in three zones in both the rivers; upper, middle and down streams. At each zone 200-meter stream reach was selected for assessment of habitat availability, habitat use by different life history stages of golden mahseer (fingerlings, juveniles and adults). This study was performed for three seasons: Post-winter (March-April), Pre-monsoon (May-early June) and Post-Monsoon (October-November) during 2018-2019. Adults of the golden mahseer were mostly found in deep waters (> 2 m) with cool temperature (18-23o C) and low water velocity (0-0.4m/s). Adults prefer pool habitats with sand and gravel/cobbles as the dominant substratum. Similarly, availability of juveniles and fingerlings were recorded along the river basins and mapped to see the available nursery grounds of the golden mahseer. Habitat preference and microhabitat use were analysed for the available nursery grounds. The results for both the rivers exhibited backwater pools, secondary channels and run habitats as highly used habitats of fingerlings. And, run habitats were mostly as used habitats by juveniles in these rivers. Fingerlings were mostly seen at depth ranges (0.1-0.6m) with velocity (0-1.2m/s) where dominant substratum was gravel and sand. Similarly, depth range between (0.3- >1.8m), moderate velocity (0.3- >1.2m/s) and habitats with cobbles, bed rock and gravel as substrate were used by the juveniles. Based on the habitat availability and use by golden mahseer, Habitat Suitability Curves (HSC’s) for the youngs were formulated. The study revealed that variation in the habitat use by the fish, significantly varied during the monsoons. In the present study, we also recorded other fish species co-existing with golden mahseer in Kosi and Kolhu. Various threats which harm the golden mahseer population and their habitats in Kosi and Kolhu river were recorded and possible conservation measures are discussed
The Spatial Ecology and Conservation of Seagrasses of the Gulf of Kachchh, Gujarat
(Wildlife Institute of India, Dehradun, 2024) Pathan, Sameeha Vahedkhan; Sivakumar, K.
Seagrass ecosystems provide ecosystem services that rank among the highest in economic valuation worldwide. They also provide a range of economic, social, and environmental goods and services, which greatly increase coastal communities' resilience to the impacts of climate change. As unique marine habitats, seagrass ecosystems provide shelter and food for marine species during different life stages and contribute to sediment accretion and primary production. The high diversity of marine plant and animal life supports tourism activities and provides the raw materials for medicinal, agricultural, and structural applications. Furthermore, the physical structure of seagrass ecosystems attenuates wave height and speed, protecting coastlines from erosion and storm surges. Threats to seagrass ecosystems in the coastal areas of the Gulf of Kachchh include pollution, rising sea levels, eutrophication, reduction of light intensity and die-back. These all negatively impact seagrass ecosystems, such as increasing growth of epiphytes, sediment anoxia, or increased prevalence of diseases. Further, the effects of climate change on seagrass ecosystems will be additional stressors. The underlying factors affecting seagrass ecosystems are direct human pressures such as pollution, disturbances, and eutrophication. The combined stressors – human pressures and climate change impacts – are likely to exceed the thresholds for seagrasses, leading to, among other things, i) redistribution (reduction and coastal migration) of existing habitats and ii) widespread seagrass ecosystem die-off. In this context, this study was conducted between January 2018- March 2022 and aimed to understand the phenology, biomass and spatial distribution patterns of seagrasses of the GoK, using which I attempted to understand the foraging behaviour, habitat use and movement ecology of dugongs in the Gulf of Kachchh. The major objectives of the study include a) Mapping the distributional characteristics and patterns of seagrass meadows in the southwestern GoK, b) understanding the seasonal variations in the abundance of seagrasses on topographically distinct meadows, c) investigating fine-scale and topographical determinants of dugong habitat preferences and d) to assess the role of semi-diurnal tides' influence on dugong foraging habitats.
Vegetation Structure Distribution and Carbon Sequestration Potential of Mnagroves Along Soil Salinity gradient in Coringa Wildlife Sanctuary Andhra Pradesh
(Wildlife Institute of India, Dehradun, 2015) Anand, Dipak; Gopi, G.V.; Sivakumar, K.; Badola, Ruchi
This study was carried out with aim of understanding the mangrove dynamics along with carbon storage abilities of various mangrove species that occur in the Coringa Wildlife Sanctuary and also the various environmental factors that would probably determine the mangrove structure, their distribution and carbon sequestration potential, from December 2014 to May 2015.