Vaishali K. Choudhary
S.H.Mutha College Of Arts ,Commerse& Science.
Biological diversity or biodiversity is that part of nature which includes the differences in genes among the individuals of a species, the variety and richness of all the plant and animal species at different scales in space. Everything that lives in an ecosystem is part of the web of life, including humans. Maintaining a wide diversity of species in each ecosystem is necessary to preserve the web of life that sustains all living things. Any of the animals or plants is removed from the ecosystem, the food chain and food web will be affected and this will have serious effect on biodiversity. Therefore, it is very essential that the ecosystems are maintained properly, so that the biodiversities are not affected.
Keyword: biodiversity; hotspots; endemism; species richness; species diversity; protected areas.
Introduction: The term Biodiversity was first coined by Walter G. Rosen in 1986. The biosphere comprises of a complex collections of innumerable organisms, known as the Biodiversity, which constitute the vital life support for survival of human race. Biological diversity, abbreviated as biodiversity, represent the sum total of various life forms such as unicellular fungi, protozoa, bacteria, and multi cellular organisms such as plants, fishes, and mammals at various biological levels including gens, habitats.
What is biodiversity?
Biological diversity or biodiversity is that part of nature which includes the differences in genes among the individuals of a species, the variety and richness of all the plant and animal species at different scales in space, locally, in a region, in the country and the world, and various types of ecosystems, both terrestrial and aquatic, within a defined area. The word BIODIVERSITY originates from the Greek word BIOS = LIFE and Latin word DIVERSITAS = VARIETY or DIFFERENCE. The whole word BIO DIVERSITY generally therefore means: VARIETY OF LIFE
Why is biodiversity important?
Everything that lives in an ecosystem is part of the web of life, including humans. Each species of vegetation and each creature has a place on the earth and plays a vital role in the circle of life. Plant, animal, and insect species interact and depend upon one another for what each offers, such as food, shelter, oxygen, and soil enrichment. Maintaining a wide diversity of species in each ecosystem is necessary to preserve the web of life that sustains all living things.
Levels of biodiversity:
The three level of biodiversity are ecosystem diversity,genetic diversity and species diversity.
Ecosystem diversity: It is the effective number of different species that are represented in a collection of individuals diversity refers to the diversity of a place at the level of ecosystems.
Genetic diversity: The level of biodiversity refers to the total number of genetic characteristics in the genetic makeup of a species.
Species diversity:The number or variety of species in a particular region.
Biodiversity Hot Spots:
Biodiversity hotspots are the large regions containing exceptional concentrations of endemism and experiencing high rates of habitat loss. Biodiversity hotspots are a method to identify those regions of the world where attention is needed to address biodiversity loss.
A biodiversity hotspot is a biogeographic region with a significant reservoir of biodiversity that is under threat from humans. Areas which exhibit high species richness as well as endemism are termed as Hotspots of Biodiversity.Myers introduced this term, at that time 25 Hotspots were identified out of which 2 were in India. Later 9 were added more bringing a total to 34.About 40% terrestrial & 25 % vertebrate are endemic found in this hotspots. After tropical rain forests the second highest number endemic species are found in Mediterranean.. India have two Biodiversity Hotspots- East Himalayan Region and Western Ghat.
Threats to biodiversity
These hotspots are threatened by human activities. More than 1 billion people most whom are desperately poor people, live in these areas.
Loss of habitat:
The reasons for loss of habitat are continuous increase in human population and escalating demand for our natural resources. There is mass conversion of forested land to agriculture.Loss of habitat to grazing land, industries, roads and cities.Habitat loss leads to the formation of isolated, small, scattered populations. These small populations are increasingly vulnerable to inbreeding, which causes loss of gene pool, high infant mortality and susceptible to environmental changes, which all may lead to extinction of the species.
Animals are hunted for various body parts.Illegaltrade of skins, tusks, hair, horns.International market very active in Tibet, China forTiger skins, elephant tusks etc.
Global Warming and Climate Change:
As temperatures increased in recent decades, certain species began breeding and migrating earlier than expected. Other studies found that the geographical range of numerous species had shifted pole ward or moved to a higher elevation, indicating that some plants and animals are occupying areas that were previously too cold for survival.Decline in breeding populations is observed.
Categories of the species under threat:
There are 9 clearly defined categories into which every species in the world (excluding :micro-organisms) can be classified.
EXTINCT (EX) :A species is Extinct when there is no reasonable doubt that the last individual has died. No reasonable record for last 50 years.e.g Indian Cheetah
EXTINCT IN THE WILD (EW) :A species is Extinct in the Wild when it is known only to survive in cultivation, in captivity or as a naturalized population (or populations) well outside the past range. e.g Mulberry Silk moth
CRITICALLY ENDANGERED (CR): This includes species, which are facing an extremely high risk of extinction in the wild in the immediate future. The population of such species is very low and the threats to its habitats are very high. E.g. Asiatic Lion.
ENDANGERED (EN) :It includes species that are not critically endangered but are in danger of extinction if the threats to its survival continue operating. Also, species whose numbers have been reduced to a critical level or whose habitats have been so drastically reduced are deemed to be in immediate danger of extinction. E.g. Tiger.
VULNERABLE (VU): It includes species that are not endangered but are likely to move into the endangered category in the near future if the threats to its survival continue operating. It also includes species whose populations are still abundant but are under threat from severe adverse factors throughout their range. E.g. Giant Clam.
NEAR THREATENED (NT):Species is Near Threatened when it has been evaluated against the criteria but does not qualify for Critically Endangered, Endangered or Vulnerable now, but is close to qualifying for or is likely to qualify for one of these categories in the near future. E.g. Nicobar pigeon.
Rare:This includes species with small populations in the world that are not at present endangered or vulnerable, but are at risk. These species are usually restricted within specific geographical areas or habitats or are thinly scattered over a more extensive range. E.g. Himalayan rafflesia.
NOT EVALUATED (NE) :Aspecies is Not Evaluated when it is has not yet been evaluated against the criteria.
LEAST CONCERN (LC):Aspecies is Least Concern when it has been evaluated against the criteria and does not qualify for Critically Endangered, Endangered, Vulnerable or Near Threatened. Widespread and abundant taxa are included in this category.
DATA DEFICIENT (DD):A species is Data Deficient when there is inadequate information to make a direct, or indirect, assessment of its risk of extinction based on its distribution and/or population status
Mumbai’s wildlife inhabitants that are surviving alongside the city’s rapid development
As we have seen that the biodiversity hotspots are threatened by human activities. But still there are many places where people are trying to conserve the biodiversity. Mumbai, the financial hub of Maharashtra, is also infamously known as the concrete jungle due to rampant development, much at the cost of environment. Here’s a consolidated list of locations that harbour the city’s flora and fauna categorised as birds, flamingos, snakes, butterflies, mangroves, flowers and bats. The good news is that most of these locations are accessible to the public and one can go out and spot these by themselves.
SPECIES: Rose-ringed Parakeet, Common Myna, Oriental White-eye, Oriental Magpie-robin, Eurasian Wryneck, Red-vented Bulbul, Common Tailorbird and Indian Grey Hornbill.
SPECIES: Pied Starling, Red-whiskered Bulbul, Black Drongo, Indian Peafowl, Cattle Egret, Indian Robin, Black Redstart and Green Bee-eater.
Maharashtra Nature Park (MNP)
SPECIES: Black-winged Stilt, Purple-rumped Sunbird, Spotted Owlet, Great Egret.
Bhandup Pumping Station
SPECIES: Eurasian Spoonbill, Grey Heron, White-cheeked Bulbul, Indian Silverbill, Greater Coucal, Grey Francolin, Indian Spotbill, Western Reef Egret, Common Kingfisher and Red Avadavat.
Powai Lake and IIT campus
SPECIES: Indian Pond Heron, Little Egret, Little Cormorant, Purple Swamphen, Black Kite, Coppersmith Barbet and Shikra.
Karnala Bird Sanctuary
SPECIES: 5 species of sunbirds-Purple, Crimson-backed, Loten, Purple-rumped, and Vigors’s Sunbird, species of drongos like Black, Greater Racket-tailed, Ashy, White-bellied and Bronzed Drongo; Golden-fronted Leafbird, Rufous Woodpecker, Grey-fronted Green-pigeon, Ultramarine Flycatcher, Grey-headed Canary Flycatcher, Shama, Malabar Whistling Thrush, Orange-headed Ground Thrush, Indian Pitta and Sulpher-bellied Warbler.
Palm Beach Road
SPECIES: Greater Flamingo, Lesser Flamingo, Painted Stork, Booted Eagle, Osprey, Caspian Tern, Broad-billed Sandpiper, Dunlin, Curlew Sandpiper, Lesser Whitethroat, Common Greenshank, Green Sandpiper and Wood Sandpiper.
SPECIES: Brown-headed Gull and Black-headed Gulls, during the boat ride birds like Greater Black-headed Gull, Heuglin’s Gull, Gull-billed Tern, Caspian Tern Little Term, Common Sandpier, Eurasian Curlew, Whimbrel, Leser and Greater Sandplover, Terek Sandpiper, Ruddy Turnstone, Common Redshank, Black-tailed Godwit, White-bellied Sea Eagle, Little Stint, Orange Minivet, Black-rumpedFlameback, Paradise Flycatcher, Tickell’s Blue Flycatcher, and Common Chiffchaff.
Mahalaxmi Race Course
SPECIES: Plain Prinia, Blyth’s Reed Warbler, White Wagtail, Pied Starling, Indian Roller, Golden Oriole, Long-tailed Shirke- and Common Stonechat.
Sanjay Gandhi National Park (SGNP)
SPECIES: Common Jezebel,Baronet, Yamfly, Monkey Puzzle, Blue Mormon, Common Leopard, Common Wanderer, Common Bluebottle, Glassy Tiger, Tawny Rajah, Psyche and Great Orange Tip.
SPECIES: Common Rose, Lime Butterfly, Common Sailer, DanaidEggfly, Common Crow and Common Palmfly.
Maharashtra Nature Park (MNP)
SPECIES: Black Rajah, Common Emigrant, Blue Oakleaf, Plum Judy, Chocolate Pansy, Red Pierrot and Tailed Jay.
SPECIES: Common Emigrant, Common Gull, Striped Tiger and Blue Tiger.
Mumbai and Navi Mumbai
Mangroves are the verdant coast guards of Mumbai and form an integral part of city’s biodiversity. Despite the concretisation, Mumbai and its outskirts still has this green cover in Versova, Lokhandwala, MaladMarve, Colaba, Mahul, Dahisar, Gorai, Navi Mumbai among others.
Mangroves and forests
SPECIES: Dog Faced water snake, Wart Snake (file Snake), Indian Rat Snake, Checkered Keelback, Buff Striped Keelback, Cobra among many others are found at various parts of the city. Dog Faced water snake and Wart Snake (file snake) are estuary snakes meaning, they are found close to mangrove areas across Mumbai. Other places to sight snakes in the city are SGNP, Aarey forests and MNP.
Biodiversity is our life. If the Biodiversity got lost at this rate then in near future, the survival of human being will be threatened. So, it is our moral duty to conserve Biodiversity as well our Environment. Long- term maintenance of species and their management requires co-operative efforts across entire landscapes. Biodiversity should be dealt with at scale of habitats or ecosystems rather than at species level.
References and websites:
- Mumbai university textbook of zoology.
2. http://www.dnaindia.com/mumbai/report-mumbai-s-biodiversity-hotspots-2244230 : Mumbai’s biodiversity hot spots by Pooja Patel.