14 Hot Spots of Biodiversity

Prof. Daizy Batish

Biodiversity hotspots are areas that support natural ecosystems that are largely intact and where native species and communities associated with these ecosystems are well represented. They are also areas with a high diversity of locally endemic species, which are species that are not found or are rarely found outside the hotspot.

The concept of biodiversity hotspots was given by Norman Myers in two articles

‘’The Environmentalist’’ (1988 & 1990). In 1988 he first identified ten tropical forest ’’hotspots’’ characterized both by exceptional levels of plant endemism and by serious levels of habitat loss.

In 1990, Myers added a further eight hotspots, including four Mediterranean type ecosystems.

Conservation International (CI) adopted Myers’ hotspots as its institutional blueprint in 1989, and in 1996, the organization made the decision to undertake a reassessment of the hotspots concept. Three years later an extensive global review was undertaken, which introduced quantitative thresholds for the designation of biodiversity hotspots.

According to CI, to qualify as a hotspot a region must meet two strict criteria:

It must contain at least 1,500 species of vascular plants (> 0.5% of the world’s total) as endemics.
It has to have lost at least 70% of its original habitat OR It must have 30% or less of its original natural vegetation

In 1999, CI identified 25 biodiversity hotspots in the book “Hotspots: Earth’s Biologically Richest and Most Endangered Terrestrial Ecoregions”. Collectively, these areas held as endemics about 44% of the world’s plants and 35% of terrestrial vertebrates in an area that formerly covered only 11.8% of the planet’s land surface. The habitat extent of this land area had been reduced by 87.8% of its original extent, such that this wealth of biodiversity was restricted to only 1.4% of Earth’s land surface. In 2005 CI published an updated titled “Hotspots Revisited: Earth’s Biologically Richest and Most Endangered Terrestrial Ecoregions”.

Global Biodiversity Hotspots: World

Currently, there are 35 Biodiversity Hotspots.Overall, These hotspots once covered 15.7 percent of the Earth’s land surface. In all, 86 percent of the hotspots’ habitat has already been destroyed, such that the intact remnants of the hotspots now cover only 2.3 percent of the Earth’s land surface. The biodiversity hotspots hold especially high numbers of endemic species. Each hotspot faces extreme threats and has already lost at least 70% of its original natural vegetation. Over 50% of the world’s plant species and 42% of all terrestrial vertebrate species are endemic to the 35 biodiversity hotspots.

I. Africa

A total of 08 Hotspots in African continent hold a diversity of plant and animal life, many of which are found nowhere else on Earth.

1. Cape Floristic Region

2. Coastal Forests of Eastern Africa

3. Eastern Afromontane

4. Guinean Forests of West Africa

5. Horn of Africa

6. Madagascar and the Indian Ocean Islands

7. Maputaland-Pondoland-Albany

8. Succulent Karoo

II. Asia-Pacific

Composed of large land areas as well as islands dotting the Pacific seas, these 14 Hotspots represent important biodiversity.

1. East Melanesian Islands

2. Himalaya

3. Indo-Burma

4. Japan

5. Mountains of Southwest China

6. New Caledonia

7. New Zealand

8. Philippines

9. Polynesia-Micronesia

10. Southwest Australia

11. Forests of Eastern Australia (new)

12. Sundaland

13. Wallacea

14. Western Ghats and Sri Lanka

III. Europe and Central Asia

From the Mediterranean Basin to the Mountains of Central Asia, these four Hotspots are unique in their diversity.

1. Caucasus

2. Irano-Anatolian

3. Mediterranean Basin

4. Mountains of Central Asia

IV. North and Central America

North and Central America play host to thousands of acres of important habitat.

1. California Floristic Province

2. Caribbean Islands

3. Madrean Pine-Oak Woodlands

4. Mesoamerica

V. South America

From Brazil’s Cerrado to the Tropical Andes, South America has some of the richest and most diverse life on Earth.

1. Atlantic Forest

2. Cerrado

3. Chilean Winter Rainfall-Valdivian Forests

4. Tumbes-Chocó-Magdalena

5. Tropical Andes

Hottest hotspots

Some hot spots are much richer than others in terms of their numbers of endemics. The analysis so far has considered five key factors: numbers of endemics and endemic species/area ratios for both plants and vertebrates, and habitat loss. These factors do not carry equal weight, so they cannot be combined into a single quantitative ranking. For comparative purposes in qualitative fashion, Hear is a list of eight ‘hottest hotspots’, which appear at least three times in the top ten listings for each factor.

1. Madagascar

2. Philippines

3. Sundaland

4. Brazil’s Atlantic forests

5. Caribbean island

6. Indo – Burma region

7. Western Ghats & Srilanka

8. Eastern arc & coastal forests of Tanzania/Kenya

The leaders are Madagascar, the Philippines and Sundaland, appearing for all five factors, followed by Brazil’s Atlantic Forest and the Caribbean, appearing for four. Three of these hotspots, Madagascar, the Philippines and the Caribbean, have small areas, which further highlights their importance.

The map shows 34 biodiversity hotspots. These are the areas which are suffering biodiversity loss and where attention is needed. Originally Norman Myers gave the twenty-five biodiversity hotspots (green, coded as 1-25) and later nine hotspots (blue, 26-34) added by Mittermeier.

http://www.drishtiias.com/upsc-exam-gs-resources-BIODIVERSITY-HOTSPOT

Megadiverse countries

The concept of megadiversity is based on the total number of species in a country and the degree of endemism at the species level and at higher taxonomic levels. The World Conservation Monitoring Centre recognized 17 megadiverse countries in July 2000 including:

This group of countries has less than 10% of the global surface, but support more than 70% of the biological diversity on earth.
The concept was first developed by Russell Mittermeier in 1988, as a way to prioritize conservation action. Based on an analysis of primate conservation priorities, he found that four countries accounted for two-thirds of all primate species. The analysis was then expanded to include other mammals, birds, reptiles, amphibians, plants and selected groups of insects.
This countries representing majority of tropical rainforests, coral reefs and other priority systems. The results of the assessment were published in the Megadiversity: Earth’s biologically wealthiest nations (Mittermeier, Gil and Mittermeier eds. 1997. Cemex, Mexico).

Global Biodiversity Hotspots: Asia-Pacific

1. East Melanesian Islands

Once largely intact, the 1,600 East Melanesian Islands are now a hotspot due, sadly, to accelerating levels of habitat loss.

2. Himalaya

The Himalaya Hotspot is home to the world’s highest mountains, including Mt. Everest.

3. Indo-Burma

Encompassing more than 2 million km² of tropical Asia, Indo-Burma is still revealing its biological treasures.

4. Japan

The islands that make up the Japanese Archipelago stretch from the humid subtropics in the south to the boreal zone in the north, resulting in a wide variety of climates and ecosystems.

5. Mountains of Southwest China

With dramatic variations in climate and topography, the Mountains of Southwest China support a wide array of habitats including the most endemic-rich temperate flora in the world.

6. New Caledonia

An island the size of New Jersey in the South Pacific Ocean, New Caledonia is the home of no less than five endemic plant families.

7. New Zealand

A mountainous archipelago once dominated by temperate rainforests, New Zealand harbors extraordinary levels of endemic species.

8. Philippines

More than 7,100 islands fall within the borders of the Philippines hotspot, identified as one of the world’s biologically richest countries.

9. Polynesia-Micronesia

Comprising 4,500 islands stretched across the southern Pacific Ocean, the Polynesia-Micronesia hotspot is the epicenter of the current global extinction crisis.

10. Southwest Australia

The forest, woodlands, shrublands, and heath of Southwest Australia are characterized by high endemism among plants and reptiles.

11. Forests of Eastern Australia

Forests of East Australia Hotspot consists of a discontinuous coastal stretch along the Australian states of Queensland and New South Wales, extending inland and further west, although it includes the New England Tablelands and the Great Dividing Range. This region contains more than 1500 endemic vascular plants.

12. Sundaland

The spectacular flora and fauna of the Sundaland Hotspot are succumbing to the explosive growth of industrial forestry in these islands.

13. Wallacea

The flora and fauna of Wallacea are so varied that every island in this hotspot needs secure protected areas to preserve the region’s biodiversity.

14. Western Ghats and Sri Lanka

Faced with tremendous population pressure, the forests of the Western Ghats and Sri Lanka have been dramatically impacted by the demands for timber and agricultural land.

Protecting and maintaining biodiversity hotspots

Hotspots are not formally recognised or governed areas. However, the identification of an area as a biodiversity hotspot increases the likelihood of conservation investment. In addition, other designations for biodiversity conservation are likely to be present within these broad areas which may have more formal management structures. For example, the average protected area coverage of hotspots, based on IUCN Protected Area Management Categories I-VI, is 12% of their original extent.

Hotspot conservation initiatives

Only a small percentage of the total land area within bio-diversity hotspots is now protected. Several international organizations are working in many ways to conserve bio-diversity hotspots.

The Critical Ecosystem Partnership Fund (CEPF) is an alliance among seven non-governmental and private-sector organizations (including Conservation International). It is a global program provides grants to organizations around the world that are working to help protect biodiversity hotspots. Biodiversity hotspots are also used by major foundations and the Global Environment Facility (GEF) to target investments in global conservation.

The World Wide Fund for Nature has derived a system called the “Global 200 Ecoregions”, the aim of which is to select priority Ecoregions for conservation within each of 14 terrestrial, 3 freshwater, and 4 marine habitat types. They are chosen for their species richness, endemism, taxonomic uniqueness, unusual ecological or evolutionary phenomena, and global rarity. All biodiversity hotspots contain at least one Global 200 Ecoregion.
Birdlife International has identified 218 “Endemic Bird Areas”(EBAs)each of which hold two or more bird species found nowhere else. Birdlife International has identified more than 11,000 Important Bird Areas all over the world.
Plant life International coordinates several the world aiming to identify Important Plant Areas.
Alliance for Zero Extinction is an initiative of a large number of scientific organizations and conservation groups who co-operate to focus on the most threatened endemic species of the world. They have identified 595 sites, including a large number of Birdlife’s Important Bird Areas.
The National Geographic Society has prepared a world map of the hotspots and ArcView shape-file and metadata for the Biodiversity Hotspots including details of the individual endangered fauna in each hotspot, which is available from Conservation International.

Biodiversity Hotspots of India

Just 17 of the world’s 200 or so countries contain 70% of its biodiversity, earning them the title “megadiverse.” India is one of these megadiverse countries with only 2.4% of world land area & 4% of fresh water, yet accounts for 7.3% of recorded species making it 3rd most mega diverse country (after Brazil & Costa Rica) with highest concentration of species in Agasthymalai Hills in Western Ghats.

Group	Number	% of world species
Mammals	350	7.6%
Birds	1224	12.6%
Amphibians	197	4.4%
Reptiles	408	6.2%
Fishes	2546	11.7%
Flowering plants	15000	6%

http://conceptedu.blogspot.in/2013/03/biodiversityhotspots-in-india-india.html

Major hotspots of endemic and genetic diversity of India.

1.Himalaya: Includes the entire Indian Himalayan region (and that falling in Pakistan, Tibet, Nepal, Bhutan, China and Myanmar)

2.Indo-Burma: Includes entire North-eastern India, except Assam and Andaman group of Islands (and Myanmar, Thailand, Vietnam, Laos, Cambodia and southern China)

3. Sundalands: Includes Nicobar group of Islands (and Indonesia, Malaysia, Singapore, Brunei, Philippines)

4.Western Ghats and Sri Lanka: Includes entire Western Ghats (and Sri Lanka)

(Source : http://www.bsienvis.nic.in/Database/Biodiversity-Hotspots-in-India_20500.aspx)

1. Himalaya

This region encompassing Bhutan, north eastern India, and southern, central, and eastern Nepal.
The abrupt rise of the Himalayan Mountains from less than 500 meters to more than 8,000 meters results in a diversity of ecosystems that range from alluvial grasslands and subtropical broad leaf forests along the foothills to temperate broad leaf forests in the mid hills, mixed conifer and conifer forests in the higher hills, and alpine meadows above the tree line.

Biodiversity

The Himalayan hotspot has nearly 163 globally threatened species (both flora and fauna) including the One-horned Rhinoceros [Vulnerable], the Wild Asian Water buffalo [Endangered].
There are an estimated 10,000 species of plants in the Himalayas, of which one-third are endemic and found nowhere else in the world.
The area has long been recognized as a rich centre of primitive flowering plants and is popularly known as the ‘Çradle of Speciation’.
S pecies of several families of monocotyledons, Orchidaceae, Zingiberaceae and Arecaceae are found in the area. Gymnorperms and Pteridophytes (ferns) are also well represented here.
The area is also rich in wild relatives of plants of economic significance e.g. rice, banana, citrus, ginger, chilli, jute and sugarcane.
It is also regarded as the centre of origin and diversification of five palms of commercial importance, namely coconut, arecanut, palmyra palm, sugar palm and wild date palm. Tea (Thea sinensis) has been cultivated in this region for the last 4,000 years. Many wild and allied species of tea, the leaves of which are used as a substitute for tea, are found in the North East, in their natural habitats.
The Taxol plant (Taxus wallichiana) is sparsely distributed in the region and is listed under the red data category due to its overexploitation for extraction of a drug effectively used against cancer.
A few threatened endemic bird species such as the Himalayan Quail, Cheer pheasant, Western tragopan are found here, along with some of Asia’s largest and most endangered birds such as the Himalayan vulture and White-bellied heron.
Mammals like the Golden langur, The Himalayan tahr, the pygmy hog, Lang-urs, Asiatic wild dogs, sloth bears, Gaurs, Muntjac, Sambar, Snow leopard, Black bear, Blue sheep, Takin, the Gangetic dolphin, wild water buffalo, swamp deer call the Himalayan ranged their home.

2. Indo-Burma

Species diversity and endemism

Taxonomic Group	Species	Endemic Species	Endemism (%)
Plants	13,500	7,000	51.9
Mammals	433	73	16.9
Birds	1,266	64	5.1
Reptiles	522	204	39.1
Amphibians	286	154	53.8
Freshwater Fishes	1,262	553	43.8

http://bsienvis.nic.in/files/Biodiversity%20Hotspots%20in%20India.pdf

The Indo-Burma region encompasses several countries. It is spread out from Eastern Bangladesh to Malaysia and includes North-Eastern India south of Brahmaputra river,Myanmar, the southern part of China’s Yunnan province, Lao People’s Democratic Republic, Cambodia, Vietnam and Thailand.
The Indo-Burma region is spread over 2 million sq. km of tropical Asia.Since this hotspot is spread over such a large area and across several major landforms, there is a wide diversity of climate and habitat patterns in this region.

Biodiversity

Much of this region has been deteriorating rapidly in the past few decades.
This region is home to several primate species such as monkeys, langurs and gibbons with populations numbering only in the hundreds.
Many of the species, especially some freshwater turtle species, are endemic.
Almost 1,300 bird species exist in this region including the threatened white-eared night-heron [Endangered], the grey-crowned crocias [Endangered], and the orange-necked partridge [Near Threatened].
It is estimated that there are about 13,500 plant species in this hotspot, with over half of them endemic. A wide array of orchid and ginger species (there are more than 1,000 orchid species in Thailand alone) and many tropical hardwood trees, including commercially valuable dipterocarp species and teak (Tectona grandis).

3. Western Ghats and Sri Lanka

http://bsienvis.nic.in/files/Biodiversity%20Hotspots%20in%20India.pdf

Species diversity and endemism

Taxonomic Group	Species	Endemic Species	Endemism (%)
Plants	5,916	3,049	51.5
Mammals	140	18	12.9
Birds	458	35	7.6
Reptiles	267	174	65.2
Amphibians	178	130	73.0
Freshwater Fishes	191	139	72.8

http://bsienvis.nic.in/files/Biodiversity%20Hotspots%20in%20India.pdf

Western Ghats, also known as the “Sahyadri Hills” encompasses the mountain forests in the southwestern parts of India and highlands of southwestern Sri Lanka.
These regions have moist deciduous forest and rain forest. The region shows high species diversity as well as high levels of endemism.
Sri Lanka, which lies to the south of India, is also a country rich in species diversity. It has been connected with India through several past glaciation events by a land bridge almost 140kn wide
The entire extent of hotspot was originally about 1,82,500 square kms, but due to tremendous population pressure, now only 12,445 square Km or 6.8% is in pristine condition.

Biodiversity

The wide variation of rainfall patterns in the Western Ghats, coupled with the region’s complex geography, produces a great variety of vegetation types.
Some prominent genera and families are represented by large numbers of endemic species, such as Impatiens with 76 of 86 species endemic, Dipterocarpus with 12 of 13 species endemic, and Calamus with 23 of 25 species endemic. Of the 490 tree species recorded from low- and midelevation forests, 308 species are endemic. The only gymnosperm tree, Podocarpus (= Nageia) wallichianus, is also endemic. Of the 267 species of orchids, 130 are endemic.
There are over 6000 vascular plants belonging to over 2500 genera in this hotspot, of which over 3000 are endemic. Much of the world’s spices such as black pepper and cardamom have their origins in the Western Ghats. Nearly 235 species of endemic flowering plants are considered endangered.
Similarly, plant diversity and endemism in Sri Lanka are quite high, with 3,210 flowering plant species in 1,052 genera, of which 916 species and 18 genera are endemic. Amazingly, all but one of the island’s more than 55 dipterocarp species is found nowhere else in the world. In addition, the island’s ferns (although not recently assessed) are estimated to number about 350 species. Approximately 433 plant species, and at least five genera, are confined to Sri Lanka and the Western Ghats combined.
Rare fauna of the region include –Asian elephant, Niligiri tahr, Nilgiri langur, Flying squirrel, Indian tigers, lion tailed macaque [All Endangered], Indian Giant squirrel [Least Concern], etc
The highest concentration of species in the Western Ghats is believed to be the Agasthyamalai Hills in the extreme south. The region also harbors over 450 bird species, about 140 mammalian species, 260 reptiles and 175 amphibians. Over 60% of the reptiles and amphibians are completely endemic to the hotspot.
Remarkable as this diversity is, it is severely threatened today. The vegetation in this hotspot originally extended over 190,000 square kms. Today, its been reduced to just 43,000 sq. km. In Sri Lanka, only 1.5% of the original forest cover still remains

4. Sundaland

http://bsienvis.nic.in/files/Biodiversity%20Hotspots%20in%20India.pdf

Species diversity and endemism

Taxonomic Group	Species	Endemic Species	Endemism (%)
Plants	25,000	15,000	60.0
Mammals	380	172	45.3

Birds	769	142	18.5
Reptiles	452	243	53.8
Amphibians	244	196	80.3
Freshwater Fishes	950	350	36.8

http://bsienvis.nic.in/files/Biodiversity%20Hotspots%20in%20India.pdf

Sundaland is one of the biologically richest hotspots on Earth. The United Nations declared the islands a World BiosphereReserve in 2013.
It is a region in South-East Asia that covers the western part of the Indo-Malayan archipelago. It includes Thailand, Malaysia, Singapore, Brunei and Indonesia. India is represented by the Nicobar Islands.
The islands have a rich terrestrial and marine ecosystem that includes mangroves, coral reefs and sea grass beds.
It has about 25,000 species of vascular plants, 15,000 (60%) of which are found nowhere else. One plant family, the Scyphostegiaceae, is confined to the hotspot and is represented by a single tree species, Scyphostegia borneensis from Borneo.
Notable plants in the hotspot include members of the genus Rafflesia, represented by 16 species with very large flowers. One of these, Rafflesia arnoldii, has the largest flowers in the world, measuring up to one meter in diameter.
The marine biodiversity includes several species such as whales, dolphis, dugong, turtles, crocodiles, fishes, prawns, lobsters, corals and sea shells.
The primary threat to this biodiversity comes from over exploitation of marine resources. In addition, the forests on the island also need to be protected

Hope spots

A hope spot is an area of ocean that merits special protection because of its wildlife and significant underwater habitats.
Andaman and Nicobar & Lakshadweep Islands have been named as the new “hope spots” by IUCN & oceanographer Sylvia Earle of Mission Blue, an organization involved in the study of oceans.
Andamans & Nicobar Island has some of world’s unique species of birds and plants. In the case of Lakshadweep, the coral reefs are quite sensitive to the ocean environment and that needs protection.

Biodiversity importance of hotspots

The biodiversity importance of hotspots is due to the high vulnerability of habitats and high irreplaceability of species found within large geographic regions. This means that these areas and the species present within them are both under high levels of threat and of significant global value based on their uniqueness. Therefore, operations that occur within global biodiversity hotspots should follow rigorous biodiversity assessments to prevent further biodiversity loss within these areas. This is a global scale approach based on coarse scale ecoregions that therefore, has limited use for site-scale assessment and decision making. Biodiversity hotspots will include areas of high biodiversity importance as well as degraded land and urban areas and therefore more detailed assessments are needed to locate the actual distribution of biodiversity within these areas.

Social-cultural values of hotspots

Given the richness of hotspot ecosystems, hotspots are often areas which offer essential ecosystem services. It is estimated that biodiversity hotspots, despite comprising 2.3% of the Earth’s surface, account for 35% of the global ecosystem services. Furthermore, hotspots are home to 2.08 billion people which add significance to the ecosystem services that they provide. Biodiversity hotspots can include a variety of human land-uses, rural and urban, as well as protected areas under a range of possible governance types therefore many social and/or cultural values are likely to be present in some parts. This however is irrespective of the identification of the area as a biodiversity hotspot.

Reasons for biodiversity loss in hotspots

There are four main reasons why species are being threatened in these biodiversity hotspots

1.Habitat destruction: As recently as 30 years ago, most of the regions in these biodiversity hotspots were inaccessible and remote. Now, due to better infrastructure, contact of these areas with humans has increased. Activities such as logging of wood, increased agriculture, increased human habitation has led to destruction of forests and pollution of rivers. These factors are causing species ranges to reduce and habitats to become choppy. The government planned to establish habitat corridors, but these plans have not yet materialized in most areas. Activities such as mining, construction of large dams, highway construction has also caused significant destruction of habitats.

2.Resource mismanagement: Increased tourism without proper regulation has led to pollution and environmental degradation. Prime example are pilgrimage destinations like Rishikesh and hill stations like Dehradoon. These spots, once nestled in the pristine ranges of the Himalayas, are now dirty commercial destinations. Places like Dehradoon are even experiencing a construction boom so large that illegal immigrants from Bangladesh are also flocking there. Religious destinations in the Himalayas, where devotees flock in millions now, are also hot destinations for medicinal plant trade, which has threatened plant life in the area.

3.Poaching: Large mammals such as the tiger, rhinoceros and the elephant once faced the distinct possibility of complete extinction due to rampant hunting and poaching. However, efforts by conservationists since the 1970s has helped stabilize and grow these populations. Still, the trade in tiger hide, elephant tusks, tiger teeth, rhinoceros horn remains profitable and rampant.

4.Climate change: Although dire IPCC predictions of Himalayan glaciers melting by 2035 have been retracted, there is no doubt that several Himalayan glaciers are melting. In the Western Ghats, studies have shown that the deciduous and the evergreen forests of Karnataka are the most at risk. Climate change may significantly affect the temperatures, rainfalls and water tables in the Western Ghats, according to an assessment by the Government of India.

you can view video on Hot Spots of Biodiversity

References:

1. Books

Textbook of Environmental Studies for Undergraduate Courses By Erach Bharucha

Research paper

Chitale VS, Behera MD, Roy PS. 2015. Global biodiversity hotspots in India: significant yet under studied. Curr Sci. 108: 149–150.
Myers N, Mittermeier RA, Mittermeier CG, Da Fonseca GA, Kent J. 2000. Biodiversity hotspots for conservation priorities. Nature. 403: 853-858.

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