Loss of Biodiversity
Loss of Biodiversity
Alteration and loss of the habitats: the transformation of the natural areas determines not only the loss of the vegetable species, but also a decrease in the animal species associated to them
Introduction of exotic species and genetically modified organisms: species originating from a particular area, introduced into new natural environments can lead to different forms of imbalance in the ecological equilibrium. Refer to, “Introduction of exotic species and genetically modified organisms”.
Pollution: human activity influences the natural environment producing negative, direct or indirect, effects that alter the flow of energy, the chemical and physical constitution of the environment and abundance of the species;
Climate change: for example, heating of the Earth’s surface affects biodiversity because it endangers all the species that adapted to the cold due to the latitude (the Polar species) or the altitude (mountain species).
Overexploitation of resources: when the activities connected with capturing and harvesting (hunting, fishing, farming) a renewable natural resource in a particular area is excessively intense, the resource itself may become exhausted, as for example, is the case of sardines, herrings, cod, tuna and many other species that man captures without leaving enough time for the organisms to reproduce.
Biodiversity Loss : Reasons
Man has begun to overuse or misuse most of these natural ecosystems
Due to mindless and unsustainable resource use, once productive forest and grasslands have been turned into deserts, and wastelands have increased all over the world
Rapid industrialization, urbanization, and growth in population have resulted in massive deforestation and consequential habitat loss around the world
For instance, mangroves have been cleared for fuel-wood and prawn farming, which has led to a decrease in the habitat essential for breeding of marine fish
Scientists have estimated that human activities are likely to eliminate approximately10 million species by the year 2050. It is also estimated that at the present rate of extinction about 25 percent of the world’s species will undergo extinction fairly rapidly
Poaching of wildlife
Poaching of wildlife for trade and commercial activities has been on the rise for the last many decades
Example : whales and many African large mammal, Asian tigers, etc. Most extinction over the past several hundred years is mainly due to overharvesting for food, fashion, and profit
Illicit trade in wildlife in current times is driving many species of wild animals and plants to extinction. Elephants are poached for ivory; tigers and leopards for their skin; pangolins for meat and scales; and rare timber is targeted for hardwood furniture.
The global illegal wildlife trade is estimated to be between $7 billion and $23 billion in illicit revenue annually. It is now considered the most lucrative global crime after drugs, humans, and arms
The Sustainable Development Goals has laid down specific targets to combat poaching and trafficking of protected species.
Man-wildlife conflict refers to the interaction between wild animals and people and the consequential negative impact on both of them.
World Wide Fund for Nature (WWF) defines this conflict as “any interaction between humans and wildlife that results in a negative impact on human social, economic, or cultural life, on the conservation of wildlife population, or on the environment.”
Although man-wildlife conflict is as old as human civilization, in modern times the degree of conflict has been on the rise due to high rise in human population in the past several centuries.
Since human populations expand into wild animal habitats, natural wildlife territory is displaced. Reduction in the availability of natural prey/food sources leads to wild animals seeking alternate sources.
Habitat loss also results from man’s introduction of species from one area into another, disturbing the balance in existing communities.
In the process, the purposely or accidentally introduced organisms (Eupatorium, Lantana, Hyacinth, Congress grass or Parthenium) have led to the extinction of many local species.
Invasive Alien Species
Overharvesting of plants for Pharma Industry
Overharvesting of fishes, corals, wood
Water Pollution, Thermal Pollution, Plastic waste, Ocean Dumping and oil spills are various types of pollution that have direct impact on the biodiversity and is responsible for its loss
IUCN Category of Species
Extinct (EX):Species not definitely located in the wild during the past fifty years but which may survive in cultivation. ‘Extinct in the wild’
Endangered (EN): Species in danger of extinction (within a few decades) and whose survival is unlikely if the causal factors continue to operate. 50% decline in the last 10 years. Critically Endangered (CR) if 50% decline in the last 10 years.
Vulnerable (VU): Taxa likely to move into the endangered category in near future. 50% decline in last 20 years
Rare (R): Taxa with small populations that are not endangered or vulnerable at present but are at risk are included under this category
Indeterminate (I): Species considered definitely to be endangered, vulnerable or rare but for which information is insufficient to categorically assign them to any of these three categories