Species at Risk and their Habitats
Biodiversity The variety of life in a particular ecosystem
Species Richness The number of species in an area
What is a Species at Risk? A plant or animal that is at risk of extinction because of threats caused by humans such as building golf courses roads cultivating native prairie.
Some species in Canada have already disappeared Plains Grizzly Bear Black-footed Ferret
Levels of Risk Special Concern a species that may become threatened because of certain biological characteristics and identified threats Polar bear Red-headed woodpecker
Threatened a species that may become endangered unless factors reducing its survival are not changed wood bison humpback whale
Endangered at imminent threat of extirpation or extinction Swift fox Northern Cricket frog
Extirpated gone from the wild in Canada, but not other parts of the world Atlantic Walrus Paddlefish (from Northwest Atlantic) (from all of Canada)
Extinct no longer exist anywhere Sea mink Great Auk
Habitat Changes affect all species in the area. For species that are already at risk, these changes can have strong negative effects from which the species may not be able to recover. Can you name some habitat changes that occur naturally?
Natural Habitat Changes Fire – naturally created by lightening strikes
Natural Habitat Changes Storms and other weather events – hurricanes, tornadoes, wind, hail, drought Storms and other weather events – hurricanes, tornadoes, wind, hail, drought
Natural Habitat Changes Animals – some animals modify their habitat to make it more suitable for them but less suitable for other animals (eg. beavers, prairie dogs)
Natural habitat changes are usually temporary and reversible. a natural process within the ecosystem. Species that live in these habitats have often evolved with these natural changes and adapted to them.
Human-caused Habitat Changes Resource Extraction = logging, mining and farming Can destroy the habitat of many species
Human-caused Habitat Changes Pollution can have far-reaching effects such as acid rain and changes in the chemistry of lakes and rivers
Human-caused habitat changes often cause long-term effects that are permanent. Species are often negatively affected by these sudden, unexpected changes to which they often cannot adapt.
Invasive Species A non-native species whose intentional or accidental introduction negatively impacts the natural environment
Examples in Ontario Starlings brought from England in hopes they would control insect pests (original 100 now up to 200 million) which have caused a decline in the songbirds. Asian Carp Sea lamprey Zebra mussels Silent invaders https://www.google.ca/search?q=silent+invaders&oq=silent+invaders&aqs=chrome..69i59j69i57j0l4.10684j0j7&sourceid=chrome&ie=UTF-8
Types of Impact: Ecological decline of native species, change ecosystem Dynamics Economic may damage crops, disease, etc Tourism species loss, reduced water quality Health disease causing organisms, pesticides to control invasive species
Controlling Introduced Species: Chemical control pesticides Mechanical control physical barriers or removal Biological control intentionally introduced species to control invasive species