Mammalian Biodiversity: How to save the icons of biodiversity?

Debananda S Ningthoujam *

Prelude

Mammals are charismatic animals and are known as icons of biodiversity. But mammals as a group are now in a precarious condition. 1 in 4 mammals are currently threatened with extinction. 1141 mammalian species out of a total of 5487 species reported by IUCN are now considered threatened to various degrees.

What are mammals?

Mammals are a class of vertebrates who suckle their young ones. There are about 1200 genera, 153 families and 29 orders and 5400 species of mammals. The class mammals are divided into 2 subclasses: the Protheria and the Theria, which includes the Placentals and live-bearing marsupials.

Most mammals belong to the placental group. The three largest orders are rodentia (mice, rats, and beavers etc.), Chiroptera (bats), and Soricomorpha (shrews, moles and solenodons etc.). Indonesia has the maximum number of mammals estimated at 670 species. South America, Africa, and South East Asia have the most diverse groups of mammals.

Habitats

Mammals thrive in several types of habitats. The major mammalian habitats are:
Terrestrial mammals

• Forests(about 4000 species)
• Savannahs(> 900 species)
• Grasslands(about 1200 species)
• Shrub lands(1500 species)
• Arid and semi-arid lands(~400 species)
• Caves and subterranean habitats (400 species)
• Artificial terrestrial habitats (about 1500 species)

Aquatic mammals

• Artificial freshwater(450 species)
• Marine neritic(50 species)
• Marine oceanic(110 species)
• Intertidal zones(100 species)
• Coastal/supratidal zones(70 species)
• Artificial marine habitats(100 species)

No mammals have been found in deep benthic zones.

What do mammals eat?

Mammals have to consume a large amount of food to maintain their body temperatures. Food differs from genus to genus. Some mammals are herbivores, some carnivores, and while some others such as humans are omnivores. Some of the major types of mammalian food are:

• Insects: pangolins, anteaters etc.
• Fruits: bats etc
• Meat: whales, dolphins, dogs, tigers, lions etc.
• Plants: cows, horses, panda, beavers, sloths etc
• Meat and vegetables: men, some types of bears etc.

Threats to mammalian diversity

• Habitat loss: more than 2000 species are affected by habitat loss and degradation
• Overhunting: about 1000 species are affected mostly in Asia
• Accidental mortality
• Pollution
• Noise pollution
• Invasive alien species(IAS)
• Catch-nets and ocean vessels
• Oil spills
• Forest wild fires
• Diseases
• Natural disasters
• Climate change
• Miscellaneous causes

Destruction and degradation of habitats due to burgeoning human population is a prime driver for decline in mammalian populations worldwide. Industrial development, cash crops or monocultures, wetland draining, mining and road construction pose serious threats to mammalian biodiversity. Mammals are seriously threatened by overhunting especially in Asia.

Marine mammals are increasingly threatened with catch-nets, fishing vessels, ocean liners, oil spills and noise pollution etc. Many mammals also suffer from serious diseases which are aggravated by the worsening climate change. We need to take up immediate measures to mitigate the threats and enhance the welfare of the mammals-terrestrial as well as marine.

Why conserve mammals?

Why save mammals in the wild? Can't we keep them in the zoos? There are myriad reasons for conserving mammalian biodiversity in the wild.

Some of the major motivations are due to the fact that they provide many ecosystem services that include:

• Nutrient cycling
• Disease control
• Seed dispersal
• pollination
• Scavengers
• Food chain links: mammals are critical links in the food chains of several ecosystems as they act as predators and prey.

Besides the above reasons, there are moral and aesthetic reasons for conserving mammals. They have the same right to exist on this planet as we humans. Also many mammals such as tigers and lions are symbols of majesty, grace, and charisma. We need to preserve them so that the future generation will inherit a biodiverse planet from us.

How to conserve mammalian diversity?

Some of the short-term programs may include:

• Creation of conservation parks
• Provision of funds
• Technology transfer
• Ecological economic accounting
• Protection of indigenous peoples' interests so that they are encouraged to protect mammals
• Monitoring of environmental assets
• Checking of deforestation
• Protection of habitats
• Creation of urban green patches & Backyard gardens
• Making governments and common people aware of importance of bird conservation
• Taking pro-active steps to control climate change

Coda

Recently the Yangtze River dolphin, also known as baiji to Chinese, has become extinct. A beautiful creature is thus gone for ever. Many other charismatic mammals such as mammoth and sabre-toothed tiger got extinct long ago. Several more are poised between survival and extinction. Which side of this fine balance will mammals ultimately go depend on the human beings and human activities.

Let's save the icons of biodiversity before time runs out. Because if all our mammalian friends become extinct, it will not he long before Homo sapiens also go extinct!

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* Debananda S Ningthoujam wrote this article for The Huieyen Lanpao (English Edition)
The author teaches biochemistry in Manipur University and researches on biodiversity and biotechnology areas especially microbial biodiversity and biotechnology. He also writes popular science articles on scientific biography and science, environment & biodiversity issues. This article was webcasted on August 06, 2010.

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