5 THREATS TO BIODIVERSITY By: Candice Waddle ES 225: Tashi Land Module 2 – Homework “The Arts” Resources Listed in the Notes

What is Biodiversity? A measure of the variety of kinds of organisms present in an ecosystem.

Threat 1: Habitat Loss The IUCN estimates that about 80 percent to 90 percent of threatened species are under threat because of habitat loss or fragmentation.  Habitat loss occurs when human activities result in the conversion of natural ecosystems to human-dominated systems.  The resulting changes eliminate or reduce the numbers of species that were a part of the original ecosystem.

Threat 2: Overexploitation According to the IUCN, overexploitation is responsible for over 30% of endangered species of animals and about 8% of plants.  Overexploitation occurs when humans harvest organisms faster than the organisms are able to reproduce.  Overexploitation has driven some organisms to extinction and threatens many others.

Threat 3: Introduction of Exotic Species The IUCN estimates that about 30 percent of birds and 15 percent of plants are threatened because they are unable to successfully compete against invasive exotic species.  Globalization is responsible for spreading thousands of invasive alien species around the world.  These species are not only the second greatest threat to native biodiversity but can also be harmful to human health.

Threat 4: Predator and Pest Organisms  The systematic killing of certain organisms because they interfere with human activities also results in reduced biodiversity.  Many large predators have been locally exterminated because they preyed on the domestic animals that humans use for food.

Threat 5: Climate Change 30 percent of amphibian species are threatened because of the effects of climate change.  The role of climate change on the survival of species has become an issue. Many species exist near the limit of their physiological tolerance.  Three groups of organisms are greatly affected by climate change: amphibians, corals, and arctic species.

What’s Being Done to Preserve Biodiversity  The main step being taken is to simply educate people on the problem, organisms, and species.  Legal Protection  Monitor biological diversity.  Establish a system of protected areas.  Identify components of biological diversity important for its conservation.  Working on sustainable management of wildlife and fish populations.

Do Your Part!! Help Preserve Biodiversity Thank You for Watching.