Biodiversity

HIPPO H – Habitat Destruction I – Introduced Species P- Pollution P- Population Growth O – Over-consumption

Habitat Destruction - #1 threat to biodiversity Agriculture Urban development Forestry Mining Environmental pollution

Impact of Introducing a New (invasive) Species Transplanted populations grow exponentially in a new area Non-native species out-compete native species Lack of competitors and predators Reduce biodiversity

Introduced (invasive) Species Brown Tree Snake arrives in Guam (stowaway on a cargo plane) and drove several local bird species to extinction. No competitors, predators, or parasites to slow the increasing population of snakes.

Impact on indigenous species when exotic (invasive) species are introduced Names (exotic/native?) 2. Where - happening and from 3. Why (intentional or accidential?) 4. Answer the question Hawaiian islands were becoming infested with rats, so Mongoose, from Asia (also found in Africa and some places in Europe) were introduced to control the rat population. Mongoose are agile and cunning carnivores that prey on insects, snakes, lizards, chickens, and rodents. What happens when the rats are gone??

Pollution Oil spills Water Cycle transports pollutants (pesticides used on land end up in water) Pollutants in atmosphere (burning fossil fuels releases sulfur and nitrogen oxides- thousands of miles away, falls to earth as acid rain). Water may be unsuitable for fish and other wildlife.

Biological Magnification Chemical pesticides (toxins) become concentrated as they pass through the food chain.

Population Growth- human activities cause rising levels of greenhouse gases Greenhouse Effect Sunlight hits the Earth’s surface and is converted to heat energy that is radiated back into the atmosphere. Some heat escapes into space and some is trapped in the atmosphere by greenhouse gases (carbon dioxide, methane, water vapor) Leads to global warming

Over-consumption Overexploitation of wildlife by harvesting at rates that exceed the ability of populations to rebound. Rare trees are harvested for valuable wood Tigers, whales, American bison, Galapagos tortoises: numbers reduced by commercial harvesting, poaching, or sport hunting Gorillas and chimpanzees: killed for bush meat (exported worldwide)