1. Chapter 3.3 How Introduced Species Affect Ecosystems
Lamprey in great lakes, costs millions in fisheries
Bullfrog
Himalayan blackberry
Scotch Broom
Starlings

2. Road map for today Go over and mark WB pages 46-49 Warm up game
Native vs. non-native
species
Invasive species and
their impacts (4)
Workbook pages
52-55

3. What’s happening here?

4. Warm-up game: Name That (Invasive) Species
Himalayan blackberries

5. Warm-up game: Name That (Invasive) Species
Scotch Broom

6. Warm-up game: Name That (Invasive) Species
Giant hogweed

7. “A public health hazard, hogweed's clear, watery sap has toxins that cause photo-dermatitis. Skin contact followed by exposure to sunlight produces painful, burning blisters that may develop into purplish or blackened scars.”
-Noxious weeds, King County, Washington

8. Warm-up game: Name That (Invasive) Species
Norway Rat

9. Warm-up game: Name That (Invasive) Species
Indian and South Pacific Oceans = native habitat
Video

11. Native species vs. non-native species
Native species are plants and animals that naturally inhabit an area
Introduced species new species of plants and animals introduced accidentally or on purpose
A.K.A. foreign species, non-native species, exotic species, or alien species
Many of these species are harmless, or sometimes even beneficial
Occurred due to immigration over past 400 years

12. Invasive species
Organisms that can take over the habitat of native species or invade their bodies, thus weakening immune system.

13. Invasive Species
Often have high reproductive rates, are aggressive competitors, and lack natural predators in new habitats
Have potential to dramatically change ecosystems through
Competition
Predation
Disease and parasitism
Habitat alteration

14. Impacts of invasive species
Competition: invasive species compete against native species for essential resources such as food and habitat
Predation: invasive species can have more impact on a prey population than native predators, as prey may not have adaptations to escape or fight them off
American Bullfrog

15. Impacts of invasive species
Disease and Parasitism: can weaken the immune response of an ecosystem’s native plants and animals, influencing humans
Allows opportunity for less dominant species to outcompete other species
European Starling
outcompetes western bluebirds
for nesting habitat
Norway Rat
Eats ground-nesting
sea birds’ eggs

16. Impact of Invasive Species
Habitat alteration: make a natural habitat unsuitable for native species by changing its structure or composition
E.g., scotch broom acidifies soil
Change light level
Decrease dissolved O2
Change soil chemistry
Increase soil erosion

17. West Nile Virus
Introduced to U.S. in 1999, started causing deaths in birds and illness in humans in NY
Carried by mosquito
How is this related to invasive species?

18. Pick two Silent Invaders http://www.youtube.com/watch?v=9JQ6oHjpeqU
Spit
Death Scent
Silent Invaders (2:58)
Spit (1:52)
Death scent (1:39)

19. Habitat alteration
Eurasian Milfoil first ID’d in Okanagan Lake in 1970.
Forms wide, dense mats at lake surfaces
Cuts off sunlight
Interferes with boaters/swimmers
Can grow from fragments  spreads!!!

20. Saving an Ecosystem Under Siege
Often requires human intervention to save established ecosystems
Garry Oak Ecosystem Recovery Team (GOERT) is trying to save several areas because Garry Oak trees:
Are a Keystone Species
May be better suited for future than Douglas fir forests
Scotch broom, and English ivy are biggest threats

21. Garry Oak Forests
95% of the original ecosystem has been lost to urban development
The remaining 5% is threatened by invasive species.

22. Cleaning up the fragments of the chapter
Native species
Non-native species
Invasive species
Impacts of invasive species (4)
Workbook pages
Next class…Ch3 review!
Coming up… Ch 3 Celebration
of Learning! 