My Science School

Spanning 8,000 sq.km., the Galapagos Islands is an archipelago located in the Pacific Ocean. It is situated about 1,000 km from mainland Ecuador, the country it is part of. It comprises more than 100 islands, including a few that are inhabited. As much as 97% of the total area of the archipelago has been declared a National Park (human occupation in the region occurs in the rest of the 3%). The areas surrounding the region have been declared a marine reserve, and are one of the richest marine ecosystems in the world. The region nurtures hundreds of plant species, a dozen native land mammal species, over 35 reptile species and nearly 3,000 marine species. It is home to unusual wildlife such as marine iguanas, giant tortoises, and flightless cormorants. The region today faces several threats, including unsustainable and illegal fishing practices. Such practices endanger both native and migratory species. So, to protect the islands, scientists, conservationists, and NGOS have been calling for the expansion of the current Galapagos Marine Reserve to protect an additional 4,00,000-odd sq.km.

Wildlife

Ducks, teals, pintails, shovelers, junglefowl, grebes, flamingoes, penguins, albatrosses, petrels, shearwaters, tropicbirds, frigatebirds, boobies, cormorants, pelicans, herons, egrets, ospreys, crakes, hawks, gallinules, coots, stilts, oystercatchers, plovers, godwits, sandpipers, phalaropes, skuas, gulls, terns, pigeons, doves, cuckoos, owls, swifts, kingfishers, flycatchers, swallows, martins, mocking birds, warblers, and finches are among the several species of birds found in the Galapagos Islands. The mammals seen in the region include several species of whales, including killer whales, sperm whales, blue whales, and humpback whales, dolphins, sea lions, seals, rodents, and bats. The reptiles include tortoises, sea turtles, marine iguanas, land iguanas, geckos, lava lizards, and sea snakes.

Did you know?

• It was the birds and animals in the Galapagos Islands that helped Charles Darwin come up with the ground, breaking Theory of Evolution", dramatically altering the way humankind had perceived its own history till then.


• According to a 2019 study, the waters off the Galapagos Islands have about 10 times more alien marine invertebrates than previously recorded. It recorded as many as 53 non-native marine invertebrates off two islands in the archipelago. The number of such species known earlier was just five! Researchers are convinced there are certainly more such creatures in the region waiting to be discovered.


• While the Great Barrier Reef is perhaps the most popular for coral reefs, the Galapagos hosts its own share of such reefs too. However, the El Nino event in 1982-83 is said to have wiped out about 90 % of shallow-water corals in the islands. To add to the problem, there were El Nino events in 1997-98, and 2015 too. However, towards the end of December 2017, a reef project carried a study in the region, and made a delightful discovery that corals were thriving in some of the remotest islands of the Galapagos.


• In a study involving sperm whales and spanning nearly three decades, researchers discovered that "two clans dominated the waters near the Galapagos decades ago, but whales from across the Pacific basin". For the discovery, the team studied distinctive communication clicks among sperm whales to track several cultural clans in the Pacific Ocean".


• In 2016, scientists discovered that two subspecies of the songbird vermilion flycatcher-found only on the Galapagos Islands-were actually two species, and gave them two different names too. While one of them Pyrocephalus nanus is commonly found in the region, the other Pyrocephalus dubius was last seen in 1987, and is, sadly, perhaps, extinct. The study used "molecular data from samples of museum specimens."

 

Picture Credit : Google

Centred on the North Pole, the almost perennially ice-covered Arctic is a polar region. It comprises the Arctic Ocean, and spans the U.S., Canada, Greenland, Iceland, Norway, Sweden, Finland, and Russia. The dominant biome (ecological area) of the Arctic is the tundra, which offers different kinds of landscapes from lowlands to mountains for plant and animal life. The tundra is characterised by low temperatures, high winds, and more than half a year without sunlight, resulting in a harsh climate. This means the biodiversity in the region is low, and only those plant and animal species that can adapt survive.

Wildlife

Due to its geographical location, the Arctic does not boast a variety of native trees, birds, animals, etc. But, it does make up for this with huge numbers in terms of population and uniqueness. The region is home to around 2.000 species of plants, including grasses and flowering plants. But they have a very short window to grow-about two months in summer. Some of the resident and migrant birds here include ravens, owls, ptarmigans, ducks, swans, plovers, curlews, falcons, hawks, gulls, buntings, fulmars, kittiwakes, terns and geese. The mammals in the region include the polar bear, seals, caribou, Arctic wolf, Arctic fox, Arctic hare, Arctic squirrel, musk ox, and rodents such as lemmings and voles. Due to the low temperatures, there are hardly any reptiles or amphibians in the tundra.

Threats

• Over the last three decades, the Arctic has warmed at about twice the rate as the rest of the world. This phenomenon has been called Arctic amplification. In essence, the Arctic is the fastest warming region globally. Scientists are of the view that this is a signal of human-induced climate change. The impact of the warming has been telling. Both floating sea ice in the Arctic Ocean and snow cover on land are decreasing. Meanwhile, many of the regions glaciers are retreating. Permafrost-the permanent frozen ground in many places within the Arctic is thawing.


• In addition to thinning ice and warming waters, the region has been witnessing long longer summers and shorter winters. This has an impact of the lifecycle of the vegetation and the animals of the region. For instance, polar bears depend on sea ice to hunt. But thinning ice means that much less access to food. There have been instances of polar bears entering residential localities in search of food. In the long-term, the lack of access to food would mean weaker cubs, and eventual extinction of local populations.


• The Arctic plays a vital role in keeping the world's climate balanced, and changes here will have an impact not across just the Northern Hemisphere, but across the globe. For instance, the Arctic's vast white ice cover sends back some of the sun's rays into space, keeping overall temperatures across the world even. So, when this ice cover shrinks, it absorbs more rays, leading to higher temperatures, and this vicious cycle will keep continuing.


• Among the other threats to the region are air pollution (black carbon from diesel engines can settle on the snow): industrial activities (mining and drilling can damage the fragile tundra habitats): and invasive and migrating species (the depletion of food sources and hosting of parasites, etc.).

 

Picture Credit : Google

Covering several African countries and an area of more than 90 lakh sq.km., the Sahara Desert is the world's largest hot desert. Also the largest non-Polar desert, it is bordered by the Atlantic Ocean, the Mediterranean Sea, the Red Sea, and the Niger River. Though a desert, only a part of the region is marked predominantly by sand sheets and dunes, while shallow basins, gravel-rich plains and rocky plateaus make up a huge part of the remaining areas. The region is home to more than two million people and nurtures a variety of plants and wildlife.

Wildlife

The mammals found in the region include the fennec fox, jerboa (a rodent), critically endangered addax (antelope), domesticated camels. gazelles, jackals, hyenas, baboons, and hedgehogs. Amphibians and reptiles include frogs, toads, crocodiles, lizards, snakes, chameleons, and skinks. Among the over 300 resident and migratory bird species found in the Sahara desert are the ostrich, buzzards, kestrels, falcons, kites, eagles, vultures, hawks, harriers, bustards, crakes, coots, geese, grebes, shelducks, ducks, pochards, bitterns, egrets, herons, teals, storks, cormorants, plovers. sandpipers, gulls, terns, sandgrouses, pigeons, doves, cuckoos, owls, nightjars, swifts, bee-eaters, larks, warblers, flycatchers, wheatears, wagtails, pipits, buntings, and sparrows.

Dust storms

Dust storms happen often over dry regions, especially deserts. Usually, tiny grains of sand carried by the wind return to the ground in a matter of hours. But the really tiny ones can remain in the air for a very long time and even be carried thousands of kilometres away through the wind. And that is what happens at the Sahara every year. The dust storms carry minute sand particles as far as the Caribbean, the U.S. and the Amazon region. It can lead to haze, affect the climate, and cause several health issues to humans - from skin problems to asthma. But the dust storm is not without its benefits either. The tiny particles of sand are loaded with nutrients that feed the Amazon. Loaded with phosphorus, potassium, and calcium, the particles fertilise the aquatic and terrestrial ecosystems there.

Did you know?

• Expectedly, climate change is one of the worst threats facing the Sahara. Though it has a harsh terrain and seems inhospitable, the desert has a very fragile ecosystem. Which means, even a slight change-say, an unusual amount of rain during just one season - can drastically alter and affect the balance in the region. This change in the environment would affect the wildlife too.


• The region has the ideal conditions to generate solar energy. "Each square metre receives, on average, between 2.000 and 3.000 kilowatt hours of solar energy per year, according to NASA estimates." According to Forbes, "We could power the entire world by harnessing solar energy from 1% of The Sahara". And, Morocco has gotten on with it, thanks to the Noor Complex Solar Power Plant set up in the region. But the question is, is it viable? One of the disadvantages of having solar panels in a place as hot as the Sahara is that when the panels get too hot, their efficiency drops. Only time will tell how feasible this project is.


• Within the Sahara, the number of domestic animals around waterholes is high. During years with good rainfall, the number of livestock increases. Which means, these animals could deplete water and wild vegetation varieties and deny the wild animals a chance at survival.


• Among a number of human activities that threaten the Sahara are development projects and the cutting down of whatever little green cover is present for firewood. This affects perennial vegetation, alters the ecosystem, and eventually increases the area of barren land.

 

Picture Credit : Google

Extending from the Atlantic Ocean in the east to the Andes mountains in the west the Amazon rainforest runs through eight countries in South America - Brazil, Bolivia, Peru, Ecuador, Colombia, Venezuela, Guyana, and Suriname. It is the world's largest rainforest, spanning over five million sq.km., and covering almost half of the continent. Considered one of the most biodiverse places in the world, the rainforest is home to millions of species of animals, birds, insects, and plants, and also to a large number of tribes. The rainforest has a structured layer of trees growing towards the sun, soaring over 100 feet, and below them, two or three levels of shade-dependent trees, all thriving harmoniously and welcoming a variety of wildlife. In addition to the rainforest, the Amazon Basin offers a range of ecosystems such as floodplain forests, savannahs and rivers. A large part of these forests is drained by the Amazon River Small wonder the rainforest is often referred to as the Earth's lungs!

Wildlife

Due to varied ecosystems, most of them nurtured by the rivers, the region teems with wildlife. But the presence of large land-dwelling mammals is relatively less (though now rare, one of the most noted big cats here is the jaguar). As if to make up for this, the number of tree-dwelling species is high, and includes a large number of bats, sloths, marmosets, tamarins, and other monkey species. Tapirs, deer, and water buffalo, and rodents such as porcupine, squirrels, and rats have made the region their home. The reptile varieties found here include iguanas and boas, the most noted being anacondas, the largest living snakes. Over 2.500 species of fish, including cat fish and piranhas, are found in the area, in addition to the more than 8,000 species of insects from ants, flies, wasps, and bees to scorpions, spiders, bugs, butterflies, and cicadas. Alligators, turtles, manatees, dolphins can be seen in the area's waters. The variety of birds found in the region is also high, and includes water birds such as herons, cormorants, spoonbills, and ibises. The forest also nurtures different types of eagles, hawks, woodpeckers, kingfishers, parakeets, macaws, toucans, quails, tinamous, and nightjars, among others.

Threats

Forest fires in the region do happen fairly regularly. However, over the last few years, the area it covers and the intensity with which it happens has been a cause of deep concern, and has been getting global attention. While forest fire is a natural phenomenon, there has been much speculation that in many instances if they were human-made, as part of deforestation, another grave concern in the region. Especially in Brazil, where the Amazon has its widest cover, deforestation has been growing at an alarming rate over the last few years. And, when the COVID-19 pandemic hit the region, deforestation just got worse. According to a BBC report, "Deforestation jumped 55% in the first four months of 2020 compared with the same period last year, as people have taken advantage of the crisis to carry out illegal clearances." In addition, logging and illegal mining too have been on the rise, and scientists warn that at such a rate, the region could hit a point of no return. Meaning, at some point in the near future, the world's largest rainforest may no longer function the way it has been doing all along.

 

Picture Credit : Google