Cover Story

The mesmerising Maldivian island Climate change has hit islands hard with some in danger of disappearing completely as sea levels rise. Being the most vulnerable ecosystems with regard to climate change, there is a need to frame effective adaptive and A. BIJU KUMAR management policies specifically for the islands.

Global warming and , if Kiribati. The people of low-lying continued unabated, would affect the islands in Vanuatu, also in the Pacific, very existence of the nation and have been evacuated as a precaution, therefore the nation’s government is though the island still remains above HE world’s first underwater developing a plan to evacuate the entire the sea. The impacts of climate change cabinet meeting organised by country to new homes in Sri Lanka, are more pronounced in some low- the Maldivian president on 17 or Australia in case of need! lying Pacific island nations as they are October 2009 was a symbolic The alarm bell is ticking not just slowly being submerged by the rising Tcry for help over rising sea levels that for the Maldives but also for many water levels of the Pacific Ocean.As the threaten the tropical archipelago’s islands across the globe. The New seas continue to swell, they will existence. This island archipelago Moore Island of India in the Sunderbans swallow whole island nations, from the nation off the tip of India, best known has been consumed recently by the Maldives to the Marshall Islands, rising sea—even as was for its mesmerising beauty and inundate vast areas of countries from also claiming its right over it! The New sparkling beaches, represented by Bangladesh to Egypt, and submerge Moore is not the first island to be 1,200 atolls, 80% of which are no more parts of a large number of coastal cities. submerged in the Sunderbans. The first than a metre above sea level, is among The islands are much more vulnerable inhabited island to have been the most threatened by rising seas. to the impacts of climate change and submerged by the rising sea level was In 2007, the United Nation’s subsequent sea level rise. Intergovernmental Panel on Climate Lohachara. Once home to about 10,000 people, the island was submerged Change (IPCC) warned that a rise in What is Special About Island sea levels of between 18 and 59 under the sea in 1996. The submerging centimetres by 2100 would be enough of islands also results in migration of Biodiversity? to make the Maldives virtually people making them “environmental Islands encompass a diverse range of uninhabitable. The economy of this refugees”. territories, differing in landform, Indian Ocean island nation is The first uninhabited island to climate and biogeography. Nearly one supported by climate-sensitive vanish from the map due to sea level fourth of the world’s countries are activities like fishing and tourism. rise was the Pacific atoll nation of islands! With the legacy of a unique 8 SCIENCE REPORTER, September 2010 Cover Story

Underwater cabinet meeting organised by the Maldivian President as a symbolic event on the impacts of climate change (left)

Lohachara Island in the Sunderbans (bottom left);

The Lakshadweep Islands— threatened! (bottom)

evolutionary history, islands are Compared to the mainland, 572 islands in the territory, of which treasure troves of biodiversity. The islands have a disproportionately high only approximately 38 are species may become island dwellers number of endemic species. For permanently inhabited. Andaman and either by drifting or by dispersal. Once example, 50% of endemic bird areas are Nicobar Islands are blessed with they reach the islands, they are confined found on islands. Over 90% of unique tropical rainforests, made of a to small, isolated pockets, much away Hawaiian island species are endemic. mixed flora with elements from from the mainland. The formation of In Mauritius, about half of all higher Indian, Myanmarese, Malaysian and new islands and their isolation from plants, mammals, birds, reptiles and endemic floral strains. So far, these the mainland provides many amphibians are endemic, and the Islands are home to about 2,200 unoccupied niches for species to adapt Seychelles has the highest level of varieties of plants, out of which 200 to. amphibian endemism in the world. are endemic. In addition to these, a In the absence of many predators The island of Cuba is home to 18 wide spectrum of uninhabited islands and competitors, the newly arrived endemic mammals, while Madagascar is there in association with the Gulf of species may easily get established in is home to more than 8,000 endemic Mannar and the Sunderbans. the new niches available. As the species. In other words, island Islands are rich in ecosystem chances of breeding with mainland biodiversity is often very unique. diversity too, as within islands we may species are limited, through isolation Lakshadweep is the tiniest Union come across mountain forests to coastal (and with restricted gene pool), they Territory of India and this archipelago wetlands. These ecosystems provide develop into distinct species, some consists of 36 coral islands, 12 atolls, food, fresh water, wood, fibre, with highly specialized characteristics. three reefs and five submerged banks. medicines, fuel, tools and other This results in a high rate of endemism, Only 10 of these islands namely, important raw materials, in addition with species restricting their Agatti, Amini, Andrott, Bitra, Chetlat, to aesthetic, spiritual, educational and distribution to localized areas. The Kadmat, Kalpeni, Kavaratti, Kiltan recreational values. In fact, the adaptive radiation and origin of new and Minicoy are inhabited. Both livelihood and economic stability of species in the islands of Galapagos inhabited and uninhabited islands are the islands depend on its biodiversity. explained by Charles Darwin is well rich in biodiversity. Similarly, the Think about corals and documented in science. Andaman and Nicobar islands include that border island ecosystems. These SCIENCE REPORTER, September 2010 9 Cover Story

Vanuatu Island

unique ecosystems provide a wide array of ecosystem services, including defence against natural disasters, support to recycling of nutrients, and Kiribati Island regulation of microclimate. They also act as homes and nursery grounds of hundreds of marine species. Above all, biodiversity of islands not only including tourism. Conversely, remote supports the economy and food Vulnerability of Islands Each island ecosystem is unique in its islands did not receive popular security of the islands but also attention, though the impacts are determines the livelihood and cultural biological character and therefore even slight changes in environmental severe. identity of 600 million island-dwelling conditions may drastically impact Over the past century, island people across the world. biodiversity and life of human species biodiversity has been subject to intense Coral reefs provide an estimated inhabiting there. These ecosystems are pressure from anthropogenic US$ 375 billion per year in goods and fragile, often comprising species that interventions in the form of habitat services to the world. This includes have evolved in the absence of destruction, introduction of invasive support for marine fisheries, which aggressive competitors, diseases or alien species, over-exploitation, and provide the principal protein source predators. Though they are more more importantly pollution and for many island populations. The biodiverse than mainland regions and climate change. Of the 724 recorded Lakshadweep is a coral island. Coral the degree of endemism is high, the animal extinctions in the last 400 years, reef ecosystems around Indian islands small size of populations and about half were island species! We have are home to hundreds of marine separation restricts movement and the classical example of Dodo in the ornamental fishes. United Nations gene flow, limiting the ability for islands of Mauritius as a symbol of Environment Programme (UNEP) recolonization following catastrophic extinction. estimated the value of coral reefs as events. Many of the islands are thickly The impacts of climate change and between US$100,000 to US$600,000 per populated and there are pressures from related events are much more square kilometre a year! human developmental activities, effervescent in islands than any other Rich biodiversity in the Lakshadweep Islands Cover Story

New Moore Island of India

TheThe NewNew MooreMoore IslandIsland ofof IndiaIndia inin thethe SunderbansSunderbans hashas beenbeen consumedconsumed recentlyrecently byby thethe risingrising sea—evensea—even asas BangladeshBangladesh waswas alsoalso claimingclaiming itsits rightright overover it!it! TheThe NewNew MooreMoore isis notnot thethe firstfirst islandisland toto bebe submergedsubmerged inin thethe Sunderbans.Sunderbans.

ecosystem in the world. The most predict that average sea level could rise of the sea and saltwater intrusion into significant impacts of climate change by as much as 21 centimetres by 2025 freshwater lenses, contributing to an are sea level and sea-surface and 66 centimetres by 2100, may lead increasing shortage of water supply temperature (SST) rise. Because most to inundation, storm surge or shoreline and loss of agricultural land. Water small islands are low lying and have a erosion, with the potential to destroy stresses caused by climate change will large exposure of coasts in relation to island economies. have terrific impacts on poor rural landmass, as well as a high Climate change is expected to people reliant on water resources for concentration of population in coastal cause serious degradation of the coastal their livelihoods. Ocean warming, zones, islands are extremely environment and natural resources on frequent tropical cyclones, flash floods vulnerable to sea-level rise. Experts which poor rural people depend. and droughts are likely to have Higher rates of erosion and coastal dramatic impact on food production A member of the land loss are expected in many islands system in islands. This would also Jarawa tribe as a consequence of the projected affect export of agricultural produce inhabiting the increase in sea level. Pacific Islands are from many island nations. Andaman & shown to be mainly vulnerable to Fisheries contribute significantly Nicobar Islands and decreased extent to the economy and rural poor of coastal vegetated wetlands. There is livelihood on many islands. As fishing also a detectable influence on marine is the major occupation of many island and terrestrial pathogens, such as coral people, the socio-economic diseases and oyster pathogens. Low- implications of fisheries loss would be lying islands as well as states and atolls severe and this may trigger other are likely to experience increased sea anthropogenic stresses such as over- flooding, inundation and salinization fishing. For example, more intense as a direct consequence of sea level rise. tropical cyclones and rise in sea surface Sea-level rise will also cause temperature will negatively impact increased salinity due to encroachment inshore fisheries and food supply, SCIENCE REPORTER, September 2010 11 Cover Story Increase in sea Increased storm/ A rise in temperature Sea level rise surface temperature cyclone frequency causes coral bleaching, which negatively affects fishes. Impact on coral reefs especially in rural areas. Not all effects of climate change on agriculture are expected to be negative. For example, increased temperatures in high- latitude islands are likely to make Shoreward retreat of Increase in wave Reduced sediment conditions more suitable for mangroves energy production agriculture and provide opportunities to enhance resilience of local food systems. The rise in sea temperature causes More exposure to More coastal More river coral bleaching, which negatively inundation erosions flooding affects fishes, sponges, giant clams, molluscs and other sea creatures, whose survival depends on reefs. As a Impacts of climate change in coastal habitats of islands result, the food security and economies of islands, which are largely dependent of fish communities. The coral phenomenon primarily due to on marine ecosystems, will be bleaching events are now frequently dependence of people on tuna, a negatively affected. The El Niño event reported from seas around pelagic fish caught abundantly in of 1998 resulted in massive bleaching Lakshadweep as well as Andaman and waters around the islands. and mortality of corals in the Nicobar islands due to increase in SST. A report issued by the World Lakshadweep, and subsequent loss of The food security of the Lakshadweep Worldwide Fund for Nature (WWF) structure, and significant alterations islands is not hit because of this argues that Australia’s Great Barrier

Coral Bleaching Corals are marine animals included in class Anthozoa and phylum Cnidaria. These organisms, producing hard exoskeleton of calcium carbonate, are represented by a colony of genetically similar flower-like structures called polyps. Over many generations the colony secretes a skeleton that is characteristic of the species. Huge deposits of these skeletons over long periods of history may give rise to coral reefs. Each polyp is typically only a few millimetres in diameter and has a skeleton cup, tentacles with stinging cells, a mouth and a stomach. The tiny tentacles snatch at passing plankton for food. Many corals form a symbiotic relationship with a class of algae, zooxanthellae, of the genus Symbiodinium. Typically a polyp harbours one species of algae. Via photosynthesis, these provide energy for the coral, and aid in calcification. The algae benefit from a safe environment, and consume the carbon dioxide and nitrogenous waste produced by the polyp. Due to the strain the algae can put on the polyp, stress on the coral often drives the coral to eject the algae. Mass ejections are known as coral bleaching, because the algae contribute to coral’s brown colouration; other colours, however, are due to host coral pigments, such as green fluorescent protein (GFP). Rising water temperatures block the photosynthetic reaction that converts carbon dioxide into sugar. This results in a build- up of products that poison the zooxanthellae. To save itself, the coral spits out the zooxanthellae and some of its own tissue, leaving the coral a bleached white. This phenomenon is often referred to as coral bleaching. Most reef-building corals normally contain around 1-5 x Bleached massive coral in Tamil Nadu coast (left); Bleached branching coral in Tamil Nadu 106 zooxanthellae per square cm of live surface tissue and coast (right). (Image Courtesy: SDMRI) 2-10 pg of chlorophyll per zooxanthella. When corals bleach they commonly lose 60-90% of their zooxanthellae and each zooxanthella may lose 50-80% of its photosynthetic pigments. The bleached coral can recover, but only if cooler water temperatures return and the algae are able to grow again. Without the zooxanthellae, the coral slowly starves to death. Apart from heat stress, other causes of coral bleaching may include: (i) increased exposure to ultraviolet (UV) radiation; (ii) large amounts of storm water from heavy rains flooding the reef; (iii) exposure of coral to certain chemicals or diseases; (iv) sediments such as sand or dirt covering the coral; and (v) excess nutrients such as ammonia and nitrate from fertilisers and household products entering the reef ecosystem. 12 SCIENCE REPORTER, September 2010 Cover Story The government of India has Defining Islands recently prepared the National An island, strictly speaking, is a piece of land surrounded by water. The Millennium Climate Change Action Plan that Ecosystem Assessment (MA), a research programme supported by the United Nations, identifies a roadmap for energy defines islands as “lands isolated by surrounding water and with a high proportion of coast to hinterland”. This definition stipulates that they must be populated, separated efficiency and sustainable from the mainland by a distance of at least two kilometres, and measure between 0.15 development. square kilometres and the size of Greenland (2.2 million square kilometres). Islands located within seas can be categorized in many ways, including by their Reef, the largest of its kind in the area. Based on altitude, islands are classified into high and low-lying islands. The world, could lose 95% of its living coral islands are also classified into inhabited and uninhabited; classification is also made by 2050 should ocean temperatures based on the density of population. They are also grouped as continental (land areas increase by the 1.5 degrees Celsius that used to be connected to the mainland) or oceanic (those that rose from the sea as projected by climate scientists. This is a result of coral deposits, volcanic activity or tectonic forces) islands. due to the phenomena of coral By a combination of the size of the land area, and political and demographic bleaching and ocean acidification. As criteria, islands are grouped into the Small Island Developing States. Countries known oceans absorb more amount of carbon collectively as Small Island Developing States (SIDS) have in common their smallness dioxide, more carbonic acid is formed, and insularity that often also indicates their vulnerability. These small island and low- resulting in ocean acidification. lying coastal countries are subject to structural vulnerability that affects their productivity, Animals with hard exoskeleton such as development and cooperation policies. Since SIDS were identified as a special group diatoms, corals and molluscs, may fall during the 1992 Earth Summit, a number of internationally agreed development goals prey to ocean acidification as their have been formulated to address SIDS vulnerabilities and to build resistance and skeleton may become weak very fast. If sustainability. Currently 52 states in the Caribbean, the Pacific, and Africa, Indian global temperatures increase by 2 °C, Ocean, Mediterranean and South China Sea are included in this category. corals may not be able to adapt quickly An archipelago is a chain or cluster of islands that are formed tectonically. It enough physiologically or genetically. is now used to generally refer to any island group or, sometimes, to a sea containing It has been estimated that, in order to a large number of scattered islands. Archipelagos are usually found isolated in bodies counter the threat of ocean acidification of water; less commonly, a large land mass may neighbour them. The five largest through global warming, a reduction modern countries that are mainly archipelagos are Japan, the Philippines, New of up to 40% of current emissions is Zealand, the United Kingdom and Indonesia. The largest archipelago in the world, needed, and up to 95% by 2050. by size, is Indonesia. Australia is geographically considered a continent, not an island, Warming may also contribute to although in the past it was considered an island country for tourism purposes. It is increase in occurrence of coral diseases. sometimes still considered an island country. A host of new coral diseases including black band disease, white 4°C, and increases of less than 2°C may handicrafts and this is linked to band disease and skeletal eroding dramatically skew the male-female sex warming of seas. The indigenous band, are now reported frequently ratios. Global warming, therefore, will people of northern Europe, Sami from the world’s oceans. have impacts on sea turtle populations, people, observed changes in species The majority of the world’s turtles majority of which prefer calm and composition in traditional reindeer have environmental sex determination, pristine beaches around islands to nest. grazing lands, which reduce sufficient which means the sex of sea turtle The islands are also well known quantity of food for the reindeer hatchlings is temperature dependent. for their human diversity and cultural populations. They depend on the Warmer temperatures increase the reindeer for food, clothing and other number of female sea turtles at the diversity. For example, the Andaman artifacts. expense of males. When the sea turtles group of islands are inhabited by four deposit eggs on the beach, the eggs are Negrito tribes, viz., the Great subject to changes in beach Andamanese, Onge, Jarawa and Adaptation and Mitigation conditions—temperature, moisture, Sentinalese and the Nicobar group of Though the developed countries and oxygen availability. The islands by two Mongoloid tribes, viz., contribute more towards climate incubation temperature of the eggs Nicobarese and Shompens. Recent change, the impacts of climate change during the first trimester of molecular genetic studies revealed the are much more effervescent in development determines the sex of the presence of these tribes in India around developing countries, including the hatchling. It has been found that eggs 60,000 years ago! As life of these island islands. The geographical location of incubated above a pivotal temperature people depends fully on the health of the countries of Asia, Africa, Latin of about 30°C develop into females and the forest ecosystems and fishing, America and Small Island states, located those below about 30°C develop into climate change events could make their in tropical and subtropical regions are males. lives more miserable. most likely to be affected by climate- Some scientists are now Decline in resources have been change impacts. There is ongoing suggesting that global climate change documented by the island communities. political and public debate on a global has the potential to eliminate the Women in the Cook Islands have scale regarding actions to be taken to production of male turtle offspring if noticed a scarcity of pupu shells which reduce or reverse future warming or mean global temperatures increase by are used by them for making local to adapt to its expected consequences. SCIENCE REPORTER, September 2010 13 Cover Story The first uninhabited island to vanish from the map due to sea level rise was the Pacific atoll nation of Kiribati. The people of low-lying islands in Vanuatu, also in the Pacific, have been evacuated as a precaution, though the island still remains above the sea.

To counter the impacts of climate interventions. These include early support, but for sustainability in future change, scientists, conservationists and warning systems and disaster as well. For example, sea walls are built policy makers are now envisaging mitigation programmes, along the coastal areas to protect combining mitigation efforts with improvements in primary health care, settlements against coastal erosion and climate adaptation measures and and coastal protection in town areas. storms. However, sea walls do not strategies. Adaptation refers to all There should be synergies solve the underlying cause of erosion those responses to climate change that between climate mitigation strategies and may cause further problems may be used to reduce vulnerability and development policies in areas such downstream. Strategic replanting of or susceptibility to harm or damage as energy efficiency, fuel substitution, mangroves might be a more efficient potential. For fighting climate change, renewables, afforestation, and land and solution to guard against periodic we need elaborate high quality data and waste management. The afforestation inundation. information on climate, and on activities in islands not only help For the islands, even though the environmental, ecological and social increasing ground water discharge, but threat of climate change is not systems affected by climate changes. also reduce pressure on natural imminent, there should be a The adaptation and mitigation ecosystems such as forests. The “precautionary approach”. These measures cannot always be led by mitigation in islands also includes include better management of governments. There should be ensuring health to coral reef and resources including biodiversity, partnerships with communities, ecosystems surrounding it. coastal habitats, land, and water, and individuals, and the private sector to There should also be alternative measures such as disease/vector frame effective measures to reduce the employment opportunities for the control and making sustainable impact of climate change on islands. island inhabitants. development plans based on the We have very little studies, including The government of India has carrying capacity of the islands. For modeling to realize the impact of recently prepared the National Climate example, the Lakshadweep and climate change on our own islands. We Change Action Plan that identifies a Andaman and Nicobar Islands of India need strong databases to study the roadmap for energy efficiency and are important tourism destinations and impact of climate change, specifically sustainable development. It also talks therefore we need to plan tourism on islands. We need separate packages about coordinating national strategic development based on the resource for adaptation and mitigation in pathways for assessment, adaptation availability and carrying capacity of islands, including community based and mitigation of climate change. the islands. Acting now would adaptation measures such as co- India is a Party to the United Nations definitely reduce vulnerability to management of coastal areas. Framework Convention on Climate extremes of climate change and Community-based programmes, Change. The National Inventory reducing the magnitude of the damage. such as vector control, water Management System (NIMS), formed Considering the fact that the conservation, coastal management, or under the Ministry of Environment and islands are the most vulnerable mangrove/coral restoration will need Forests, plans to generate a ecosystems with regard to climate the support of government and comprehensive knowledge base on change we need to frame effective nongovernmental organizations. There scientific issues related to climate adaptive and management policies should also be programmes for finding change for informed decision making specifically for the islands. Therefore, out alternative employment schemes and mitigation. Identification of in all development and planning for the island dwellers. Public vulnerabilities and hence risks activities climate change should form awareness and discussion forums associated with climate change at state the major agenda, as the underlying involving community representatives level, agro-ecological zones and agro- principle is “precaution is better than could help convey information about climatic zones enables the cure”. the impacts of climate change and gain development of adaptation consensus on the adaptation options. frameworks at these levels for a target The large student power available in sector or for the associated Dr A. Biju Kumar is with the Department of Aquatic the country can also be used for this vulnerabilities. Biology & Fisheries, University of Kerala, purpose. Some adaptation measures The planning should not be for Thiruvananthapuram-695 581, Kerala; Email: will need to rely on government temporary economic gains and [email protected] 14 SCIENCE REPORTER, September 2010