Four ways humans are threatening species
1. Habitat loss
2. Species introductions
3. Overharvesting
4. Illegal wildlife trading
greenhouse effect and global warming
increase in surface temperature caused by heat trapping gases in Earth's atmosphere; carbon dioxide absorbs radiation and re radiates it back towards Earth blocking heat escape
CO2 levels and average global temperatures
CO2 levels block heat from escaping, making temperatures go up
Degree increase in next century
1.8-4.0 degrees Celsius
What evidence are scientists seeing of global warming besides an increase in temperature? (species)
butterfly habitats North, animals mating a few days earlier, migration routes shifting
introduced species
species brought to an area where it did not previously occur
Invasive species
spreads wildly causing harm to the environment, human health, or economy
Rabbits
24 rabbits introduced in 1859; became invasive, overpopulation
Kudzu
A large leafed quick-growing vine of the Southeast
Burmese Python
these reptiles were both accidentally and intentionally introduced in the everglades in Fl. They are hard to find and kill, and they reproduce rapidly. They have huge appetites and they are competing with a keystone species, the alligator. (30,000+)
Overexploitation of cod
-over harvested Cod by fishing with draggers to get as many as they wanted
-There was a ban on fishing Cod for a while, The downfall was many people lost their jobs
Actions Canada took to put an end onto Cod fishing
1992 ban on fishing