Sustainability of Seafood

Seafood is a common source of protein and ensures food security in many coastal regions across the world. The seafood industry also has economic importance- serving consumers and exporting delicacies and popular varieties of fish, crab, shellfish, etc. However, overfishing and certain aquaculture practices have raised environmental concerns.

Is seafood sustainable?  Does the seafood industry cause environmental problems? And is seafood better than other types of meat? These are some questions that will be answered subsequently.

Aquaculture is the process of cultivating aquatic life for our consumption. This happens in natural marine habitats or in controlled environments that replicate marine habitats. There are many stages in aquaculture. The first stage is the hatchery (collecting eggs, breeding of fish). The fish are then transferred to the farm where they are grown to their full size. Then they are harvested, processed, packaged and transported to stores and markets (Global Seafood Alliance, 2019).

Environmental impacts of aquaculture

Certain species like salmon consume wild fish as their food. So, it takes more than one kilogram of wild fish to produce one kilogram of salmon (Greenberg, 2014). This leads to overfishing to meet the dietary needs of the species being cultivated.

Aquaculture also generates waste through fecal matter and unused feed. The waste is nitrogen-rich and causes oxygen depletion if they are discarded in marine environments. This would choke aquatic organisms in the ocean. The use of pesticides and antibiotics in aquaculture produces chemical waste that pollutes ocean water.

Shrimp farming mostly occurs in tropical and subtropical ponds, within mangrove forests. When pollutants accumulate in shrimp farming ponds, the ponds are abandoned and cultivation is continued in a new pond. This results in the destruction of mangroves, which also host other species of fish and offer coastal protection against cyclones. Therefore, organic aquaculture has started gaining importance, to protect mangroves and sustain people’s livelihood (Greenberg, 2014).

The fishing industry also removes reproductively mature fish from their natural environment, which leads to population decline of fish. Overfishing can slow down the growth of fish population and disrupt the marine food chain. It threatens the livelihood of small fishermen who depend on the daily catch for food and income (Pariona, 2017).

Harmful fishing techniques

These are two ecologically damaging fishing techniques, that are now being banned by many countries due to the problems they cause.

  1. Bottom trawling – Fishermen drag a net along the seabed. This disturbs the sediments that had settled at the bottom. The sediments are carried to other parts of the ocean by the currents.  Accumulation of sediment creates murky water, which blocks the sunlight from reaching underwater plants, creating oxygen-deficient regions. Pollutants that had settled at the seabed are stirred up and enter the food chain, poisoning marine life.
  2. Blast fishing – Explosives are used to kill large numbers of fish at once. This destroys coral reefs and causes oceanic noise pollution (Greenberg, 2014).

Waste generated by aquaculture

Fodder waste and chemical pollutants not only pollute the local ocean water, but can be transported throughout the ocean, affecting different levels of the food chain. It could affect the growth of plankton, and subsequently reduce biodiversity.

Aquaculture waste, once treated, has many uses and economic potential. Fodder waste can be converted to biogas or as fertilizers for soil.

Chitin, obtained from the exoskeleton of crustaceans (crabs, lobsters, shrimp), is used as an additive in fish food. Chitin also has other applications in the medical field.

The process of obtaining chitin also recovers carotenoids. Shrimp waste has economic potential due to the presence of carotenoids. Carotenoids are responsible for the color in shrimp and shellfish. Once extracted and processed, they are used in the food industry and the cosmetic industry.

Compounds like enzymes and proteins could be used in the pharmaceutical industry, and the methods to extract these from seafood waste are being researched (Arvanitoyannis & Kassaveti, 2008).

Seafood production and climate change

The rising temperature of ocean waters due to global warming has reduced fish productivity and changed the distribution of fish population. This hurts seafood production, especially in the tropical countries who are most dependent on seafood for food and money.

Warmer water increases the risk of algal blooms, which will hamper aquaculture. Aquaculture farms will shift their location depending on the condition of the water and marine productivity (Palardy, 2022).

Yet, seafood has the potential to become one of the most sustainable ways of achieving food security for the future.

Seafood can be sustainable

Currently, the seafood industry is criticized for causing overfishing, water pollution and marine degradation. In spite of these environmental impacts, it has the potential to become sustainable if managed efficiently, with proper waste recycling and treatment, and policy measures to ban hazardous fishing methods and overfishing.

Seafood has higher protein retention compared to other types of meat like pork, chicken and beef. Aquaculture is more resource efficient; it has lower greenhouse gas emissions, water demand and land requirement than land-based meat production (Greenberg, 2014).

Some varieties of seafood have lower environmental impact than other varieties. For example, farmed shellfish, mollusks, sardines, mackerel and herring have low environmental impact compared to catfish aquaculture and shrimp. This is because more energy is used for water circulation in the latter.

Mollusk aquaculture (oysters, mussels, scallops) has a positive impact on marine environment because mollusks absorb excess nutrients from water, that would otherwise harm the ecosystem. Capture fisheries do not use fertilizers and thus generate less pollution compared to intensive fish farming (Ma, 2018).

Therefore, consumers also play an important role in the sustainability of seafood by choosing species that have low environmental impact for cultivation and sourcing their seafood from fisheries that follow sustainable practices.


Arvanitoyannis, I., & Kassaveti, A. (2008). Fish industry waste: treatments, environmental impacts, current and potential uses. International Journal Of Food Science &Amp; Technology43(4), 726-745.

Greenberg, P. (2014). Environmental Problems of Aquaculture. Earth Journalism Network. Retrieved 17 June 2022, from

Ma, M. (2018). Choice matters: The environmental costs of producing meat, seafood. UW News. Retrieved 17 June 2022, from

Palardy, J. (2022). Seafood Production Suffers Under Climate Change, but Sustainable Reforms Can Help Maintain Harvests. Pew. Retrieved 17 June 2022, from

Pariona, A. (2017). What Is The Environmental Impact Of The Fishing Industry?. WorldAtlas. Retrieved 17 June 2022, from

What is Aquaculture, and Why Do We Need It?. Global Seafood Alliance. (2019). Retrieved 17 June 2022, from

Deep Sea Pollution?

When we think of pollution in the seas, what generally comes to mind are oils spills, great pacific garbage patch, wildlife entanglement, and microplastic, a commonality between all these is the easy exposure due to proximity to the surface because of this less is known of the majority of pollutants affecting the oceans, are in the deep seas.

In the scope of plastic waste, over 99 percent of it is present on the ocean’s floors or midway at around 180 meters to 460 meters below sea level as opposed to the surface, to make this comparison more visceral, consider the notorious imagery of “the great pacific garbage patch” which amounts to merely a 0.29 % of the total plastic waste present in the seas due to some of the research on the distribution of plastic content in the oceans it is reasonable to assume there are four times as much present in the depths below the garbage patch. It has even been found in some of the deepest most remote parts of the Mariana trench.

Concerns arise even further when we apply this phenomenon to the other form of plastic formed due to overtime degradation of its debris, microplastics. Microplastics are known for contaminating entire ocean food chains and scientists have discovered that large quantities are carried by bottom currents to concentrated spots to form microplastic hotspots, one example is located in the Tyrrhenian Sea. These same currents are also responsible for transporting nutrients and oxygenated water, implying that the microplastic hotspots form in the same regions as significant ecosystems filled with marine life. 

Another notable scope of pollution that affects the deep sea comes in the form of chemical waste most significantly as pesticides, toxic metals, and pharmaceuticals, which come to about 100 million tons currently present, out of these the most alarming toxins identified by researchers were persistent organic pollutants, PCBs and PBDEs, both of which have been slowly phased out from widespread usage but as the category “persistent organic pollutants” suggests they stuck around in the environment to this day. Their effect can be illustrated through research conducted in the aforementioned marina trench. They are capable of traveling great distances indicative of their presence in such a remote area like the Marina trench, and they don’t dissolve well in water and favor sticking to the surface of materials such as we mentioned before deep-sea plastics. Creatures attracted by the colorful allure consume them, where the “persistent organic pollutants” remain building up in their fat tissue. Upon death, their bodies sink to the ocean floor to be consumed by deep-sea crustaceans, thus incorporated into the food web.  

Interceptor technology for rivers prevents plastic discarded in them to reach the ocean, creating an artificial coastline to remove the garbage, and several other measures undertaken to clean up the oceans are encouraging examples indicating a brighter future for the oceans, but the lack of initiatives towards the deep sea is equally as concerning.

The Beautiful Coral Reefs

Corals belong to the phylum Cnidaria, a group that include gelatinous stinging marine invertebrates like jellyfish and sea anemones.

Coral reefs are composed of the skeletons of marine invertebrates called corals and the each tiny individual coral is polyp. The coral species build reefs by extracting calcium carbonate from seawater to create a hard, durable exoskeleton that protects their soft, sac-like bodies. These are called hard corals. Other species of corals that are not involved in reef building are known as soft corals such as sea fans and sea whips.

Coral polyps live on the calcium carbonate exoskeletons of their ancestors, adding their own exoskeleton to the existing coral structure. As the centuries pass, the coral reef gradually grows, one tiny exoskeleton at a time, until they become massive features of the marine environment. Coral have an array of shapes and colors, from round, brain like to tall with intricate and vibrant colors.

Corals of different shapes, size and colors

Corals are found all over the world’s oceans, from the Alaska to Caribbean sea. However, the biggest coral reefs are found in the clear, shallow waters of the tropics and subtropics. The largest coral reef system is the Great Barrier Reef in Australia which is more than 2,400 kilometers in size.

Corals feed by one of two ways.

Most corals depend on zooxanthellae, a photosynthetic algae which lives inside the coral polyp’s body where they produce food – carbohydrates to corals and for themselves. The coral reefs inturn provides a protected environment and the components to the algae. The corals and the algae share a symbiotic relationship wher both the organisms are benefited by each other.

In addition, zooxanthellae also provide the corals with their lively colors as most coral polyps are colorless without zooxanthellae.

However, some species of corals, mostly the deep corals in the lower, colder zones of the ocean directly catch small marine life, like fish and plankton, by using the stinging tentacles on the outer edges of their bodies.

About the reproduction of the coral species, they reproduce both sexually and asexually. Asexual reproduction happens through budding when new clonal polyps bud off from the parent polyp and grow and form their own colonies. Sexual reproduction occurs during a mass coral spawning. Coral spawning is an annual event when the corals release both eggs and sperms to fertilize. Later, the fertilized eggs develop into coral larvae, which grow further and form their own colonies or reef.

Coral spawning at Great Barrier Reef

Coral reefs are divided into four categories and they are:

  • Fringing reefs – grow near the coastlines around islands. They are most commonly found in the Phillipines, Thailand, Timor-Leste, off the western coast of Australia. Ningaloo reef is the largest fringing reef along the western coast of Australia. In India, the fringing reefs are found in the Gulf of Mannar and Palk Bay.
  • Barrier reefs – similar to fringing reefs, formed when fringing reefs combine with each other and border the coast. They are separated from shores by deeper and wider lagoons.

Example: Great Barrier reef, off the northeastern coast of Australia in the Pacific Ocean.

In India, Barrier reefs can be found in Andaman and Nicobar Islands.

  • Patch reefs – small, isolated reef growing from the bottom of the continental shelf. Patch reefs are present in Ratnagiri, Malvan and Kerala coasts of India.
  • Atoll – is a ring shaped coral reef island in the middle of oceans. Kiribati atoll in the west-central Pacific Ocean is the world’s largest atoll.

The union territory of India, Lakshadweep is also an archipelago consisting of 12 atolls.

Coral reefs are mostly found in warm, clear, shallow water with plenty of sunlight to nurture the algae that the coral rely on for food. Coral reefs covering less than 1 percent of the ocean floor are the most productive and diverse ecosystems on the earth. Hence are called “rainforests of the sea”. Coral reefs are critical marine habitat as they provide home and nursing to around 25 percent of marine life including 4,000 species of fish.

Importance of Coral reefs

  • Coral reefs benefit around 1 billion people with an estimated $30 billion annually in direct economic benefit to people worldwide from the various ecosystem services it  provide including food, coastal protection, and income from tourism and fisheries.
  • They act as wave barriers protecting the coast from erosion and the costal communities of adverse climate events.
  • Attracts millions of tourists every year, adding to the country GDP.  

Threats to coral reefs

Increasing temperatures of the world’s oceans due to global warming is causing coral reefs to expel zooxanthellae. Post which the coral reefs loses their color and are deprived of food eventually leading to their death. Coral reefs losing their color is termed as Coral Bleaching which is an increasing cause of concern.

Also, ocean absorbs immense amounts of carbon dioxide released into the atmosphere through fossil fuel burning which is causing high acidification of the ocean which in turn is inhibiting coral’s ability to produce calcium carbonate exoskeletons, the shelter base of corals.

Agricultural pesticides, chemical fertilizers, sewage discharge, oil, gasoline and sediment from eroded landscapes is polluting the ocean waters, making it difficult for coral to thrive and therefore damages the complex relationships that exist among the marine life and corals.

Unsustainable fishing practices such as cyanide fishing, blast fishing  with explosives and fishing using trawlers is destroying a thousand-year-old complex coral reef system.

The destruction of coral reef around the world, can lead to the extinction of thousands of species of marine life and make coastline communities and infrastructure susceptible to havoc causing storms and cyclones. Some islands and low-lying countries would vanish under the water due to it. Also damaging the economy of various coastal countries.

Healthy corals are the foundation of the Ocean’s food chain contributing immensely to our economy. It has geographical, economical and cultural importance.

Healthy corals lead to healthy oceans, and healthy oceans are vital to all life on Earth. Hence, protecting coral reefs is of utmost importance.


Oil-Eating Bacteria: A Solution to Clean our Water Bodies

Oil spills can destroy the biodiversity of a region and can have an indelible negative impact on the environment. Since the 1970s the average number of oil spills recorded at 20 spills per year has significantly reduced in the recent past. In the decade from 2010 to 2019, the average spill recorded in a year was 1.8 (Sönnichsen, 2022). But the problem of clearing the oil from these spills regardless of the extent of damage is an arduous task. One of the solutions by way of scientific research is the discovery of oil-eating bacteria. Ever since its discovery, several initiatives have been taken to use it as a tool to clean water bodies polluted with oil-based substances like petrol and diesel.

Historical significance

Oil-eating bacteria belong to several families including Marinobacter, Oceanospiralles, Pseudomonas, and Alkanivorax, that can consume compounds of petroleum (Thrift-Viveros, 2015). There are close to 7 species of bacteria that can eat petroleum-based products as part of their diet.

The Pseudomonas bacteria were genetically engineered by Prof. Anand Mohan Chakravarthy in 1971 which received tremendous attention worldwide owing to the number of oil spills that were prevalent during the period. In the mid-1990s, other bacteria like Alcanivorax and Marinobacter were isolated.

These oil-eating bacteria have a large potential to tackle oil spills across the world since oil has almost become a part and parcel of the economic functions of a society. Even if there comes a time in the future of electric vehicles and less fossil fuel-dependent energy resources, some sections of the societal functions will be dependent on oil which would need to be transported. This would further also leave room for oil leaks to occur by external forces beyond the control of human actions for which these oil-eating bacteria will come to the rescue.

How does the bacteria’s diet work?

Oil-eating bacteria are present as communities across several regions including the Persian Gulf and Arctic conditions of Alaska. Such bacteria have the capacity to degrade hydrocarbons from where they derive their ability to eat oil (Verran, 2020). These bacteria are adapted to the climatic conditions of that region and the more adapted they are to the natural environment, the better their capacity to eat oil quickly. In addition to the climate, the amount of oxygen and nutrients in the water, temperature of the water, the surface area of the oil, and the type of oil impact the oil-eating capacity of the bacteria. For insurance, some bacteria may be in a position to consume oil more quickly from water during the summers as compared to winters and they can eat light petroleum products like gasoline and diesel better as compared to heavy petroleum products like crude oil and fuel. 

Indian context

India is not new to oil spills and has been a victim of several such spills even in the recent past. The most recent of the incidents is the Ennore oil spill in 2017 along the coast of Chennai wherein 60 tonnes of oil (Ennore Oil Spill: What Happened? 2017). The impact was felt across several ports. Dead turtles washed up on the shore as a result of the leak. Though efforts were taken to clear the same, oil-eating bacteria could have definitely enhanced the clean-up process. The argument that efforts should be taken to prevent them is necessary, but that does not solve the oil leaks that have already occurred. It is for this reason that we need oil-eating bacteria.


Ennore oil spill: What happened? (2017, November 9). The Hindu. Retrieved May 20, 2022, from

Sönnichsen, N. (2022, February 9). Global average oil spills per decade 2021. Statista. Retrieved May 20, 2022, from

Thrift-Viveros, D. (2015, June 5). Who Thinks Crude Oil Is Delicious? These Ocean Microbes Do. NOAA’s Office of Response and Restoration. Retrieved May 20, 2022, from

Verran, J. (2020, February 25). Can oil-eating bacteria clean up our seas? Microbiology Society. Retrieved May 20, 2022, from

Slippery sailors of the sea: India’s Sea snakes

In Indian mythology, Vishnu, the Lord of preservation, is said to have been supported by a giant sea snake called Shesha that rests on the cosmic ocean upon which the entire world is balanced. Snake Vasuki was wielded as a rope to churn milk from the ocean. Our myths, legends and stories have always integrated sea snakes and serpents into their storylines. Whether these stories have portrayed them as holy, higher entities or as ruthless monsters, they have familiarized the idea of sea snakes in us since our childhood. Out of the 3000 species of sea snakes found across the globe, India is endemic to 26 species according to a report catalogued by Chennai’s National Centre for Sustainable Coastal Management (NCSM).

Herpetologist Nirmal Kulkarni says that all snakes can swim. “In fact, all snakes are good swimmers and have to drink water in order to survive. Water snakes are a common grouping of snakes that are found in the vicinity of water bodies.” But land snakes and sea snakes are distinctly different from each other in their physiology, adaptations and behaviour. Sea snakes, which are largely venomous creatures that fall in the Elapidae or cobra family, have a flatter body than land snakes and own rudder-shaped tails that facilitate them in sifting through their marine ecosystem. Eyes and nostrils are situated at the top of their heads for most sea snakes. As air-breathing creatures, these features aid them in breathing with only the tip of their head peeking above the surface of the water. Although some of these slithering monsters could grow as long as 2.7 metres, most adults attain a length of 1–1.5 metres during their lifetime.

Sea snakes are categorized into two basic kinds. True sea snakes, which are labelled under the genus Hydrophis, are the ones that live their whole life exclusively in the sea. The other variety called sea kraits is segregated into the genus Laticauda and consists of snakes that favour plodding in estuaries, mangrove swamps, coral reefs and mud flats rather than in the nearby water body itself. 52 of the total sea snake species are identified as true sea snakes.

Sea snakes are predominantly found in the tropical and sub-tropical coastal regions of the Indian and Pacific oceans. The hook-nosed sea snake (Hydrophis schistosa) is the most prevalently found species in India. They are distributed across a range of deep and shallow waters. Also known as Beaked sea snakes, these are lethally venomous creatures who rely on their toxins to catch their prey instantaneously in the aquatic ecosystem. They possess a beak-like or hook-like rostral scale that protrudes above their mouth. They are usually known to prefer sea catfishes, eel-tailed catfishes and pufferfishes. Annulated sea snake (H. cyanocinctus), which has unique triangular stripes over a cream coloured body, and the many-toothed Malacca sea snake (H. caerulescens) are two other types in the Hydrophis genus or true sea snakes that are native to India.

The Rainbow Water Snakes (Enhydris enhydris) are largely freshwater snakes that pervade settings like marshlands, ponds, rice paddies etc. Two long, pale stripes run down the length of its body and intersect on the crown.

In the other category of Sea Kraits in the Laticuda genus, India is home to Banded Sea Krait (Laticauda colubrina) and Blue Lipped Sea Krait (Laticuda laticaudata). The Banded Sea Krait also referred to as yellow lipped sea krait, are nocturnal species that contain alternating markings of black with blue, white or grey rings. They also have a prominent yellow snout, thus the name Yellow lipped sea krait. These snakes crawl up into limestone caves and rock crevices to lay their eggs. The Blue Lipped Sea Krait or Blue-ringed sea krait is the reptile replica of the blue-black version of “Is the dress blue-and-black or gold-and-white?” It is found in abundance on the coasts of the Bay of Bengal.

Some other sea snakes that traverse the oceans of the Indian Ocean are Annandale’s Sea Snake (Kolpophis annadalia) and Shaw’s Sea Snake (Lapemis curtus). From Genus Rhabdops, species like Rhabdops olivaceus and the Rhabdops aquaticus populate the streams of West Bengal.

However, the continuity of these sea snakes is threatened by climate change, excessive fishing and increased human intervention. Sea snakes are found as bycatch in fishing nets and are often killed or left to die by the fishermen. Although these snakes are protected under schedule IV of the Indian Wildlife (Protection) Act, 1972, they are of no economic value to the fishermen, and that lands as a huge disadvantage to the sea snake population. A significant incident of Mass bycatch would be the one in Goa where 81 hook-nosed sea snakes were found dead over an expanse of beach shore as small as 30 meters. Tragically, the same woe repeated itself only a couple days ago with 69 dead hook-nosed sea snakes. We could prevent such incidents by directing more incentives to sea snake monitoring and research, more funds into constructing safer fishing gear etc.


  1. Distribution of Sea Snakes in the Indian Coastal Waters by P. Kannan and M. Rajagopalan
  2. Sea snakes –
  4. Threatened and undocumented sea snakes of India – Mongabay news

Through the ordeals of an island: How to survive when you’re stuck on an island by India’s coastline

From literary classics like Lord of the Flies to films like Castaway and Blue Lagoon, the “stranded at an uninhabited island” trope is extremely pervasive in the realm of fiction. The trope is so familiar that it even earned a name to it; Robinsonade. A Robinsonade is a storyline that follows one or more characters who are marooned in the wilderness due to unanticipated causes and are left to claw and scrape from what nature has to offer. However, surviving on an island post a shipwreck in real life could be harder and more dangerous than the romantic renditions that films have fed us. So how do you survive when you’re stuck in a land with only endless stretches of ocean to look at. It might be a physically and emotionally crippling process that could sway one’s judgment easily.

Therefore, the first tip that one must try their best to follow is to keep calm. Help might be on its way already, so keeping cool and not panicking will best help conserve your energy. Gather as many essentials as you could from the ship and quickly swim away (preferably breaststroke) from the shipwreck, since the sinking ship might cause suction and pull you into the water. It is always advised to be prepared with a set of requirements beforehand, like flares, a first aid kit, flashlights, batteries, mirrors to reflect on surfaces, magnifying glasses, a matchbox, drinking water, canned food etc. Carefully look for injuries on your body since an infection that isn’t nursed properly or a blood clot may reduce the odds of your survival drastically at a later stage. Former Navy Lieutenant commander Paul Hart said that the first essential you should rummage for after wreckage is ‘rubber boots’ to protect your feet.

Shelter, food and fire should be your biggest priorities if you’re abandoned on an island.

A good and safe shelter is essential to protect you from exposure to the harsh climate and predatory animals that might be around. A shelter can play a big role in saving you from a heat stroke if the weather is extremely hot, or from hypothermia if the weather is unbearably cold. Bamboo stems and palm fronds must be abundantly available in the tropical islands around the Indian coastline. Bamboo, being one of the strongest woods available, is an ideal foundation to hold up your shelter. Firmly fix a few large bamboo stems into the ground and top them with dried palm fronds, which will act as the roof.

Your chances of survival are ten folds higher if you find a freshwater source near you. A study based on modern-day hunger strikes proposes that an average human can conveniently survive without proper food sustenance for as long as two months. Yet, it takes less than 8 days without water to take down a person. Dehydration leads the cells of our body to shrink and severely impedes blood circulation, oxygen circulation and most other essential body functions for survival.

Possible sources of freshwater around you are island rivers, lakes, ponds, caves etc. Water usually collects in valleys, so moving downhill spikes up your odds of finding a waterbody. Pay attention to the direction in which animals are moving by following footprints on the ground and to which way birds are flocking towards. Plush greenery is also a good indicator that there’s a water body nearby. Lend your ears to nature while you’re resting, because you might be able to hear a stream or river running nearby. It’s strictly advised not to consume saltwater directly from the ocean, especially since the salt might cause dehydration. If it rains on the island you’re stranded on, you can also conserve rainwater in a pit. Coconut water is a ready source of water and nutrition (like potassium, vitamin C and carbohydrates) on a tropical island. Be sure to not shake the tree from the bottom to acquire the coconuts since the chances of the fruit falling on you is fatally high. Carefully climb up the tree and pluck them. Most tropical islands around the Indian coastline will house a dense growth of flora and fauna. You can feed on berries, fruits and nuts while you hunt for small animals or fish.

The crucial thing to do after finding water is to purify it. Although you might be deceived by how clean a river might look, it could be wallowing with a range of harmful bacteria and viruses. Boiling is the best way to kill microorganisms. You could break a bamboo stem and use it as a water bottle or store water in the shells of fruits or nuts. Feel free to improvise with what resources you can find around you. Carving tools out of sticks and branches could come in handy when you need a spear to catch fish, snails or crabs to eat. It’s best to avoid jellyfish, fish that have spikes or puff up. Now it’s time to build a fire, and roast some fish and moon-gaze in the dark.

The most pivotal essential, while you’re stuck on an island, is fire. It’s going to be the key source of warmth and will help repel predatory animals and insects. Collect as much wood as possible and slowly build a fire. Anything from tree barks to coir can fuel the fire, given that they’re completely dry. It’s a bonus if you began a fire on flat and dry ground close to a firewood source.

In William Golding’s Lord of the Flies, Peggy lights a fire by focusing the sun with her spectacles. This eventually became the crucial plot point that helped the stranded boys to be rescued. Fire could also save the day by catching the attention of a ship or plane that might pass the island.


  1. wikiHow – How to survive after a shipwreck
  3. – Castaways: Seven incredible stories of human survival
  4. HowStuffWorks – How to survive a shipwreck
  5. Lord of the Flies – William Golding

The Fall of the Coral Reef: Lakshadweep

Situated about 200 to 440 kilometres off the Malabar Coast, Lakshadweep is an archipelago of 36 islands in the Arabian Sea, of which 10 are inhabited. All of India’s coral reefs are Fringing reefs, except for Lakshadweep, which houses a breathtaking boundary of atoll reefs. An atoll is a ring-shaped coral reef that partially or entirely loops around a lagoon. This feature makes Lakshadweep a unique destination to check off one’s bucket list. This cherished uni-district Union Territory of India houses 12 atolls, three reefs and five submerged banks. Tourist brochures allude to its scenic beauty and the multitude of activities it offers like scuba diving at Kalpeni Island or Snorkeling at Agatti Island while advertising Lakshadweep.

Lakshadweep is a dwelling ground for a large body of diverse flora and fauna. With several species of seaweeds and seagrasses, mangroves, molluscs, marine fishes, corals, and economically and ecologically crucial species like tuna, dolphins, whales, marine turtles and sharks, the colourful Lakshadweep is a melting pot of endemic wealth. Corals constitute a major part of the island’s ecosystem and play a crucial role in controlling the conditions of the island.

Coral reefs are soft-bodied underwater ecological communities with colonies of coral polyps bound together by calcium carbonate that deposit over them with time. Although mistook as plants, corals very much fall under the category of Animalia. However, being an incredible sight for sore eyes isn’t their only purpose. As humongous, breathing systems, corals have the capacity to control global warming to a substantial level by regulating carbon dioxide in the ocean. Since corals also catalyze seagrass growth, they help form a stable seabed as a consequence. Corals, along with their surrounding biodiversity, also aid in purifying the water. Researcher R.M. Hidayathulla remarks that “The corals of Lakshadweep are the lifeblood of the islands.” They especially sustain a diverse range of marine organisms in their immediate habitat, and the deterioration of coral health is bound to affect the quality of life for these organisms and vice versa. 

The six species of seagrasses named in the islands of Lakshadweep, which include Thalassia hemprichii and Cymodocae rotundata, significantly help in fending off erosion of the beaches. The indigenous green turtles of Lakshadweep majorly feed on Thalassia hemprichii. This example is indicative of how codependent these species are on each other.

The practice of coral mining is increasingly becoming a prevalent plague in Lakshadweep. As a cheaper and abundantly available alternative to cement, the corals are predominantly used for construction activities like building roads, houses, seawalls etc. Seagrasses and weeds are predisposed to decrease when the coral numbers dwindle, therefore accelerating the erosion of seabeds. This is a major threat to the islands as it could eventually lead to the submergence of the entire island.

Other anthropogenic activities in and around coral islands like excessive fishing, poaching, lagoon dredging, and urbanization in the immediate environment of the corals also cause a threat to their existence.

However, the biggest evil looming over the islands of Lakshadweep is global warming. Increasing temperatures of seawater are not only perilous for the coral reef, but also to the entire island ecosystem. A report laid forth by the Intergovernmental Panel on Climate Change predicts that our coral reefs could undergo a mass die-off by the year 2040.

Due to increased seawater temperature, coral bleaching has become a new nightmare. The corals accommodate algae over them, with which they have a symbiotic relationship. The corals provide the algae with a home to thrive in and photosynthesize, while the algae provide nourishment to the corals. It is these algae that decorate the corals with a hue of colours.

Although the aesthetic value of the corals is the pivotal factor for Lakshadweep being a key tourist destination, the quality and health of the corals have also slowly begun trickling into the tourist discourse. One tourism agency even advertises Kadmat Island as an “Unspoiled coral mine and marine reserve” to better appeal to the public.


  1. Marine Biodiversity of Lakshadweep: An overview Basudev Tripathy
  2. Lakshadweep island – Wikipedia
  3. Excessive mining leads to declining coral reefs in Lakshadweep – The Hindu
  4. The Great Coral Grief of Lakshadweep islands by Sweta Daga –
  5. The dying corals of Lakshadweep –

The Clean for the Olive Green and Blue

Since time immemorial, Chennai’s coast has proved to be an important aspect of the city. Playing several roles such from a busy harbour, to a site of leisure and fun, life without a beach in Chennai is quite difficult to imagine! The coast is bound by the Bay of Bengal, making it an important marine ecosystem. A large variety of flora and fauna can be found along the coast of Chennai that is said to have existed for thousands of years. 

Over the last few decades, however, this ecosystem has been rapidly declining due to an uncontrolled amount of anthropogenic (environmental change caused or influenced by people, either directly or indirectly) activities along the coast. The coast that was once famous for the nesting of Olive Ridley Sea Turtles had become a site for food stalls and social activities, increasing the usage and dumping of plastic and other waste in our beach. 

Every year, between January and May, thousands of Olive Ridley Sea Turtles can be spotted on Chennai’s beaches as they make their way to lay their eggs on the very beach where they were born in! That’s what makes this coastline so beautiful. In an effort to conserve and protect this fragile ecosystem, E.F.I hosted voluntary beach cleanups over the weekends to spread awareness and clean our beaches. Take a look at the cleanups conducted so far!

The Mega Beach Clean up of January 2022

The heavy rains from the North-East Monsoons of 2021 filled up the lakes and ponds in Chennai. Somewhere else, things were not the same. Our beaches. Tonnes of waste from the city got spewed into the sea. On a fine winter Sunday morning, with a cool gush of air that had blown past us, with gloves tightened, and with sack bags in hands, our volunteers were ready to pick up non-biodegradable waste from Chennai’s fragile coast. Our day started with the collection of trash from 10 different locations in South Chennai. Locations are given below: 

  1.     Broken bridge to Olcott Kuppam stretch 
  2.     Ashtalakshmi beach
  3.     Arupadai veedu beach
  4.     4th Seaward road, Thiruvanmiyur
  5.     Palavakkam beach
  6.     Neelankarai beach
  7.     Olive beach (Injambakkam)
  8.     Injambakkam beach
  9.     Akkarai
  10.     Panaiyur     

   Beach clean up summary:

S. noLocationNo of VolunteersNo of sack bags collectedTotal amount of Garbage
1Broken bridge2401301560
2Ashtalakshmi beach1401101320
3Arupadai veedu  beach4020240
44th Seaward beach7060720
7Olive beach9460720
912 volunteers540 sack bags6468 kgs of garbage

Fabulous February

Over 250 volunteers united to stand against pollution on Sundays and emerged victorious at 3 beaches, the Ashtalakshmi Temple beach, 4th Seaward Beach and the Neelankarai Beach. Close to 2.2 tonnes of plastic and other waste were removed from these beach stretches!

The Oh-So-Blue March

The ‘Water’ month as we like to call it never ceases to amaze us. Over 6 massive cleanups were conducted along the coast, hosting over 623 volunteers as the heat began to seer on. But the summer heat didn’t stop our beach warriors! Close 6.5 tonnes of waste were removed from our beaches during this month!

April and the upcoming months

We’ve so far been able to conduct activities every weekend and will be continuing to do so in the upcoming months! We invite you to join us in this effort to clean for olive green and the blue.

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Volunteer for India and her Environment with E.F.I

Common Bivalves in Chennai

by Goutham Krishna

Kingdom: Animalia
Phylum: Mollusca
Class: Bivalvia

Bivalves are marine or freshwater molluscs characterized by a shell that is divided into two valves that are inter-connected to one another at a hinge. Bivalves are species that lack head and typical molluscan organs like radula and odontophore. Some of the primitive bivalves ingest sediments. The absence of the head and other molluscan organs of the bivalves can be explained by this largely sedentary and deposit-feeding or suspension-feeding lifestyle. Bivalves are also referred to as Lamellibranchiata and Pelecypoda in the scientific literature of the earlier centuries.

The majority of bivalves are marine and can be found in or on practically any substrate at any depth. Bivalves are common on rocky and sandy coastlines in shallow seas. Bivalves range in size from one millimeter (0.04 inch) to the enormous clam Tridacna gigas, which can grow to be more than 137 centimeters (54 inches) long. Bivalve species can be mainly categorized into clams, scallops, oysters, and mussels. Oysters are widely used for edible purposes by humans and other species. Also, bivalves are highly important in maintaining the marine food chain. Apart from marine habitats, bivalves are also seen in fresh water and brackish water.

Various species of Bivalvia are commonly seen on the Chennai coast. Some of them like Peacock mussel and White hammer oyster are used by the natives for edible purposes. Names and details of some of the bivalves common to the coromandel coast are listed below.

Ark Shell (Anadara Indica)

They are marine bivalvians belonging to the family, Arcidae. Arc shells are characterized by boat-shaped shells with long, straight hinge lines bearing many small, interlocking teeth. They are mainly found in tropical seas and hence are a common sight on the Chennai coast. They are harmless to human populations in any manner.

Two toned Cardita (Cardites bicolor)

Two-toned Cardita, known as “Vaṇṇa vari maṭṭi” in Tamil is another bivalve that is commonly seen in Chennai coast. As its name suggests, Shells of two-toned Cardita are in dual-tone. They are used for fisheries purposes and are harmless to human beings.

Cuneate Wedge Clam (Donax cuneatus)

This species is mainly seen in shallow water on beach sand. It travels between high and low tide marks with the tides, burying itself in the sand every time the waves expose it. it is usually about 2.5 cm long and is commonly found on the shores of Chennai.

Pen shell (Pinna bicolor)

Pinna bicolor is a species of bivalves belonging to the family Pinnidae. It is a tropical Bivalvia, majorly found in the Indian ocean. Henceforth it is a common sight on the coromandel coast.

Sunset Siliqua (Siliqua radiata)

Siliqua radiata is a Bivalvia belonging to the family Tellinidae) is commonly called a sunset shell. They inhabit the sandy bottom of beaches in small burrows.

Peacock Mussel (Perna viridis)

The Peacock mussel, is an economically important mussel, a bivalve belonging to the family Mytilidae. It is harvested for food but is also known to harbor toxins and cause damage to submerged structures such as drainage pipes. It is native in the Asia-Pacific region and is also common on the Chennai coast.

Dancette Clam (Sunetta scripta)

This species can be distinguished by its elongate anterior dorsal margin and slightly posterior umbo. The overall shape is elongate, ovate. The posterior margin is nearly straight and forms a distinct angle at its confluence with the ventral margin, and belongs to the family of Veneridae.

Windowpane Oyster (Placuna placenta)

The windowpane oyster (Placuna placenta) is a bivalve marine mollusk in the family of Placunidae. They are edible but valued more for their shells (and the rather small pearls). The shells have been used for thousands of years as a glass substitute because of their durability and translucence.

Trough Shell (Mactra sp)

Mactra is a large genus of medium-sized marine bivalve mollusks or clams, commonly known as trough shells or duck clams. The word “trough” in the common name refers to the fact that all Mactra shells have a large ligamental pit at the hinge line, which in life contains a large internal ligament. Most bivalves in other families have an external ligament instead.

 White Hammer Oyster (Malleus albus)

The White Hammer Oyster is one of the most unusual types of marine bivalve molluscs and is easily recognized by its greatly elongated hinge extensions and corrugated valves. Internally the shell valves exhibit a nacreous (pearly) appearance. The closely related species, the Black Hammer Oyster (Malleus malleus) has a much darker shell than the White Hammer Oyster, but sometimes occurs in the same localities

Tranquebar Scallop (Volachlamys tranquebaria)

A beautiful scallop is usually found in the Indian ocean at shallow depths. They come in an array of gorgeous colors and patterns. The first occurrence of the Tranquebar scallop Volachlamys tranquebaria in the Vellar estuary, southeast India is reported ith photographs.

Blue Button

by Goutham Krishna

Scientific name: Porpita porpita

Phylum: Cnidaria

Family: Porpitidae

Blue button, scientifically known as Porpita porpita is a marine organism found in the tropical and subtropical waters of the Pacific, Atlantic and Indian Oceans. These organisms are found on the western coast of India, which is bounded by the Arabian sea. They consist of colonies of hydroids found floating and propelling in the coastal sea waters. Their body is divided into two parts, which are the float and the hydroid colony. Float is the main body of the organism with a round / disc liked shape. The hydroid colony are elongated branches arising from the main body like tentacles. Hydroid colony is generally bright blue or yellow in color.  Carl Linnaeus was the first scientist to identify blue buttons in 1756.

Though they are commonly known as blue button Jellyfish due to their physical similarities with Jellyfishes, they are not genetically related to jellyfishes. Also, the blue buttons are organisms that cannot swim in ocean water. Instead of swimming, they are floated on the ocean surface with the assistance of winds and ocean currents. They are part of the neustonic food web, which includes all the organisms and species present on the surface of oceans. They hunt crabs and fish for feeding. Also, they are preyed on by various marine species like the sea slug, the blue dragon etc.

Blue button jellyfishes are hermaphrodites, i.e., with both male and female reproductive organs in the same species. Hence, they can produce sperms and eggs of their own. The mature polyps release eggs and sperm into the water, which fertilize on their own. After this, they turn into larvae which further develop into young polyps. These species communicate with each other with the help of pores present in its body.

These species are generally of zero economic and utilitarian importance to human beings. Though the stung of blue button jellyfishes are not seriously harmful to human beings, they can cause skin irritations. Due to global warming and the associated rise in oceanic temperature, a sudden rise in the population of Blue button Jellyfishes have been recorded in various parts of Earth. Overpopulation of these species is not good, considering their ability to create damage in the existing equilibrium of marine habitat.