Sevvandi Jayakody

• PhD
• James Hutton Institute

An annual assessment of plastic debris has been conducted since 2022 at the Accelerated Natural Regeneration of Mangroves (ANRM) site in Anawilundawa as a part of a long-term study aimed at restoring abandoned shrimp farms back to their natural vegetation. As microplastics can impact flora and fauna, it is important to quantify and identify them in...

Sri Lanka is a top plastic beaching island in the Indian Ocean. This study investigated plastic waste management in the Sri Lankan coastal zone in three stages. A database of policy and institutional management structures was constructed in MS Excel and examined to connect laws and responsible institutions. A literature survey of marine pollution r...

At a time of global interest on mangrove restoration, determining the soil characters in restoration sites are vital for two reasons i.e. to record the baselines and for establishing the changes with restored mangroves. This research focused on assessing soil characteristics: pH, salinity, electrical conductivity (EC), wet soil color, and dry bulk...

The growth of mangroves is profoundly influenced by the physio-chemical properties of their pedosphere. For the successful management and restoration of mangrove ecosystems, information on these properties is crucial. In this study, vertical profiles of soil characteristics, including pH, salinity, electrical conductivity (EC), wet soil colour, and...

The study was conducted to assess the health risks of selected metals in cultured and wild Crassostrea madrasensis in Sri Lanka over 13 months. Metal concentrations varied monthly, and Zn and Cu concentrations significantly varied between cultured and wild oysters. The mean metal concentrations (mg kg−1) were accumulated in order of Zn (1220.60) >...

Mangroves, salt marshes and seagrasses are conspicuous and important features of the Sri Lankan coastline, playing an important role in delivering multiple ecosystem services including carbon sequestration (the so-called blue carbon ecosystems). Together, they support coastal biodiversity, provide habitat and nutrition for numerous plant and animal...

The National Environmental Action Plan (NEAP) 2022-2030 is the 4th NEAP in the series starting from the plan initiated in 1990s for Sri Lanka. This NEAP fills the national environmental planning gap since the National Action Plan for Haritha Lanka Programme 2009-2016 ended its intended implementation period in 2016. The NEAP 2022-2030 is vital as i...

Oysters are considered as a nutritious seafood, but they can adversely effect on human health due to bioaccumulation potential. The current study was conducted to determine the health risks of mercury(Hg), lead(Pb), cadmium(Cd), arsenic(As), magnesium(Mg), zinc(Zn), iron(Fe) and copper(Cu) in cultured and wild Crassostrea madrasensis collected from...

The white-throated kingfisher or white-breasted kingfisher, Halcyon smyrnensis is a common breeding resident found throughout Asia. Both sexes are alike; juveniles are duller than the adults. They breed yearly from January to August in pairs, but the breeding season begins earlier in India and Sri Lanka. The most active period of breeding related a...

In 2017, Sri Lanka set a goal to increase its forest cover to 32% by 2030 (Sri Lanka UN‐REDD, 2017). However, on November 4th 2020, the government published circular MWFC/1/2020 revoking the circular 5/2001 of August 10th 2001, one of the country's most crucial forest protection directives. The revocation of the 5/2001 circular could severely hampe...

Indian Backwater oysters (Crassostrea madrasensis) are available en mass around Sri Lanka but nutritional value and seasonal changes have not been studied sufficiently. Proximate composition and percentage edibility (PE) for wild and cultured oysters in Kala Oya estuary and Puttalam lagoon were studied. Influence of environmental factors on proxima...

The Oyster Crassostrea madrasensis is abundant in Kala Oya estuary. This edible oyster is collected from both wild and cultures in Sri Lanka. As filter feeders, they are well known to accumulate toxic metals from the surrounding environment hence, quantifying nonessential trace metals and understanding spatial and temporal variations is essential....

Shrimps have become the most important part of the global aquaculture farming and world food market. However, after the industry was severely affected by the White Spot Syndrome Virus, remedial measures that are in place have not completely eradicated the problem that is affecting the livelihood of shrimp farmers and other stakeholders. Therefore,...

Many of the seasonal water bodies in Sri Lanka harbour substantial numbers of aquatic birds. Local aggregation of water fowl during communal roosting and colonial breeding results in substantial inputs of nutrients into aquatic systems and can alter fresh water aquatic systems. The present study calculated the density and species richness of true a...

Sri Lanka’s location, historic and geologic isolation from the continental landmass, topography and climate act to shape its biogeography and biodiversity, including conferring a remarkably high level of endemism, given its close proximity to the mainland. The island hosts several ‘point endemic1 species and even monotypic endemic genera. However t...

Coral reefs across the world are threatened by elevated sea water temperatures that has resulted in extensive coral mortality. Bar Reef Marine Sanctuary (BRMS) is the largest Marine Protected Area (MPA) in Sri Lanka, which was severely impacted by the 2016/2017 global mass coral bleaching. Rapid reef surveys were undertaken in 2017 and 2019. The po...

Marine mammal watching is a sub-category of wildlife tourism and has shown continual growth as a global industry. Sri Lanka is an island nation in the south of the Indian Ocean with one of the busiest whale watching industries. Three locations in Sri Lanka provide facilities for marine mammal watching enthusiasts namely Mirissa in the south-west, T...

The marketplace contains a choice of both cultured and wild oysters, often subtle differences in taste and characteristics are observed between wild and cultured oysters. Therefore, seasonal variations of total lipid and total fatty acid compositions were studied in both, wild and cultured populations of Crassostrea madrasensis in Gangewadiya in Ka...

The earliest information on Sri Lankan echinoid species belonging to the Irregularia dates back to Alexander Agassiz (1872). However, the current knowledge of diversity and distribution of irregular echinoids from Sri Lanka (formerly Ceylon) remains sparse. In addition, there are no recent taxonomic studies or biodiversity surveys for irregular ech...

The first recorded regular echinoid species from Sri Lanka, "Salmacis virgulatus" (now known as S. virgulata L. Agassiz in L. Agassiz & Desor, 1846), was listed by Agassiz & Desor (1846). Knowledge of Sri Lankan regular echinoids continued to advance until the end of the 19 th century. However, there is a gap in knowledge between the mid-20 th and...

Nutritional status of animals reveals the quality of the ecosystem that they live in. Hence, estimates on nutritional status can be a good indicator that can be used for pre and post monitoring of any ecosystem, after a management intervention. Restoration of degraded aquatic systems are currently considered for Wilpattu National Park, Sri Lanka, w...

Background: The exotic fish Poecilia reticulata is promoted in the tropics as a biological control agent for aquatic pathogenic carriers, such as mosquitoes. Such control measures are often adopted blindly, ignoring the potential of native species and the adverse effects of introduced species. The present study was conducted to assess the diet com...

The edible oyster Crassostrea madrasensis is naturally found in Kala-oya estuary and the presence of tourist industry has created small scale culture based fisheries within coastal communities. But little attention is paid towards the studies on nutritional composition of oysters. Monthly variation of total lipid and fatty acid composition were det...

Abstract Conventional chemical controlling, due to harmful effects on the environment and animal health, is less appreciated and discouraged today. The impacts to exposed organisms are multiple, but changes at nuclear level can result in long-term impacts to exposed populations. Such chemical exposure can also negatively impact fish that are intent...

Irregular echinoids are formally known as Irregularia, a group including forms such as lamp urchins ("cassiduloids", a non-monophyletic assemblage), sand dollars (Clypeasteroida) and heart urchins (Spatangoida). The group is mainly infaunal and are important components of marine ecosystems as both adults and larvae. The earliest information on irre...

A comprehensive review and analysis of the literature on echinoids from Sri Lankan waters were conducted to compile an annotated list that integrates the existing published data with original data from recent research. According to the published literature, 115 echinoid species and one subspecies have been reported from Sri Lanka to date. However,...

Background In 2015 alone there were an estimated 214 million new cases of malaria across the globe and 438,000 deaths were reported. Although indigenous malaria has not been reported in Sri Lanka since 2012, to date 247 imported cases of malaria have been identified. Knowledge of the locations, behaviour and vectorial capacity of potential malarial...

Mass aggregation of waterfowls for breeding, results in allochthonous nutrient inputs into aquatic systems. This study evaluated accumulation of bird droppings as allochthonus nutrient input and its fluctuations in Anavilundawa International Ramsar Sanctuary in Sri Lanka where Asian openbill (Anastomus oscitans) mass breeding occurs annually. Reser...

The food and feeding studies of fish are useful to explore the possibilities of using them for various purposes such as aquaculture and biological control of problematic organisms. In the current study feeding patterns and diet composition of Aplocheilus parvus (E: Killi fish/Drawft panchax), a common surface feeding predator inhabiting freshwater...

Associations between sea urchins and a wide array of other organisms including polychaetes, annelids, copepods, shrimps, crabs, mollusks, ophiuroids, asteroidi and fishes are well known. Although Stomopneustes variolaris and Tripneustes gratilla are common sea urchins along the southern and western coasts of Sri Lanka, knowledge of their associated...

Mass aggregation of waterfowls for breeding, results in allochthonous nutrient inputs into aquatic systems. This study evaluated accumulation of bird droppings as allochthonus nutrient input and its fluctuations in Anavilundawa International Ramsar Sanctuary in Sri Lanka where Asian openbill (Anastomus oscitans) mass breeding occurs annually. Reser...

Background During recent years, the contribution of man-made aqua-tic/semiaquatic habitats for breeding of malaria vector Anopheles culicifacies has increased, challenging the efforts of eliminating indigenous malaria from Sri Lanka. Some serve as important aquatic habitats with rich biodiversity while others are constructed to extract potable wate...

During the last decade, shrimp has become a major sector of global aquaculture farming in terms of space occupied and of market value. A narrow coastal belt of approx. 120 km of Puttalama district in North Western Province facilitates for more than 90% of the shrimp farming in Sri Lanka. Though remedial measures have been introduced after the indus...

Sea urchins (or regular echinoids) are one of the most common macro-grazers and keystone species in rocky shore systems. However, their ecology is little explored in Sri Lankan waters. Therefore, a study was conducted to investigate the spatio-temporal variations in the diversity and density of sea urchins off Nilwella in the Southern coast of Sri...

During recent years, the contribution of man-made aquatic/semiaquatic habitats for breeding of malaria vector Anopheles culicifacies has increased challenging the efforts of eliminating indigenous malaria from Sri Lanka. Most such man made habitats also serve as important aquatic habitats with rich biodiversity, hence chemical use is not an option....

Disturbance from human recreational activities may affect the nutrition of free-ranging herbivores due to trade-offs between feeding in preferred habitats and perceived predation risk. To test this hypothesis, we estimated diet composition for red deer in the Scottish highlands in spring, when recreational activity tends to be high, and in winter w...

Water hyacinth (Eichhornia crassipes) is a free-floating perennial aquatic plant known to be a noxious invasive in most of its invaded territories. The high productivity and absorption capacity of the plant creates a big problem for freshwater reservoirs and rivers by obstructing navigation, impeding drainage and destroying wildlife. In Sri Lanka E...

Biotic and abiotic factors that influence the avian distribution in a dry zone wetland was investigated by studying the distribution of Asian Openbill (Anastomus oscitans), Cotton Pygmy-goose (Nettapus coromandelianus) and Pheasant-tailed Jacana (Hydrophasianus chirurgus) in Anavilundawa Ramsar sanctuary in Sri Lanka in 2006. Their distribution was...

Red deer Cervus elaphus, even in wilderness areas, are increasingly exposed to disturbance from human recreation as well as hunting, and it has been suggested that both types of disturbance may be perceived as a predation risk. We studied the vigilance behaviour of red deer in the Scottish Highlands, in sites with traditionally high numbers of visi...