1. Plagues and Swarms
Invasive Species Ecology

2. Invasive Species
Invasive species are defined as non-native exotic organisms whose introduction to new areas may result in harmful effects on human and environmental health and economic costs
Invasive species are one of the most important threats to biodiversity
Approximately 50,000 invasive species in the USA
Nearly 5,000 plant species
10,000 person hours in Smoky Mountain National Park (
Emerald Ash Borer
Water Hyacinth
Emerald Ash Borer
Zebra Mussel
European Starling

3. Invasion Ecology: General Questions
- How are species able to dominate the habitats they invade? - What impacts do invasive species have on species diversity and ecosystem processes? - What determines the invasibility of habitats?

4. Invasive species impacts
Based on a 2005 Lexington, Kentucky, street tree survey- it is estimated that there are more than 10,000 ash trees in the Urban Service Area (LFUCG 2007).
The ash component of Louisville Kentucky's tree population is 17%.
buprestid

5. Asian carp

6. Invasive species impacts (critters)
European wild rabbit (Oryctolagus coniculus)
Invasive in Australia
Causes damage to the environment and agricultural operations
Difficult to control because native predators now rely on the feral rabbit as a food resource

7. Invasive species impacts (critters)
Brown Tree Snake (Boiga irregularis)
Native in Australia and Indonesia
Invasive in Hawai’i
Preys on native lizards and birds
Causes major power outages because it climbs on electrical wires

8. Invasive species impacts (critters)
Zebra Mussel (Dreissena polymorpha)
Native in Europe and Asia

9. Invasive species impacts (critters)
Zebra Mussel (Dreissena polymorpha)
Native in Europe and Asia

10. Invasive species impacts (critters)
Zebra Mussel (Dreissena polymorpha)
Native in Europe and Asia

11. Invasive species impacts (critters)
Zebra Mussel (Dreissena polymorpha)
Native in Europe and Asia
Extremly successful in filter feeding
Decrease food available for other aquatic organisms
Makes the water clear
Increase in aquatic plant production and blue-green algae
Clogs drainage pipes
Approx. $5 billion in damages to the Great Lakes

12. Invasive species impacts (critters)
Rusty Crayfish (Orconectes rusticus)

13. Invasive species impacts (plants)
Tree-of-heaven (Ailanthus altissima)
Native to China
Allelochemical properties and a distinct small
Invasive throughout the USA
Oak-hickory and Maple-birch forests
Early successional species

14. Invasive species impacts (critters)
Amur honeysuckle (Lonicera maackii)
Native to China and surrounding Asian region
Introduced to the USA in 1896 (Luken, J. O. and J. W. Thieret 1995)
Flower of L. maackii
Photos: Ryan W. McEwan
Fruit of L. maackii

16. Invasive species impacts (critters)
Amur honeysuckle (Lonicera maackii)
Native to China and surrounding Asian region
Introduced to the USA in 1896 (Luken, J. O. and J. W. Thieret 1995)
Suite of invasive characteristics (Gorchov and Trisel 2003; Hutchinson and Vankat 1997; McEwan et al. 2009)
Successful in disturbed and edge habitats
Black Oak Park in summer

17. Invasive species impacts (critters)
Amur honeysuckle (Lonicera maackii)
Native to China and surrounding Asian region
Introduced to the USA in 1896 (Luken, J. O. and J. W. Thieret 1995)
Suite of invasive characteristics (Gorchov and Trisel 2003; Hutchinson and Vankat 1997; McEwan et al. 2009)
Successful in disturbed and edge habitats
Has a long growing season
Allelopathic capabilities
Herbs (Dorning and Cipollini 2006; Cipollini et al. 2008)
Insects (Cipollini et al. 2008; McEwan et al. 2009)

18. Invasive species impacts (insects)
Asian Longhorned Beetle (Anophlophora glabripennis)
Native to China, Japan, and Korea
Invasive in NY, NJ, and PA
Larva eat away at woody tissue of many types of hardwood trees
Estimated costs of approx $3.5 billion USD/year

19. Invasive species impacts (insects)
Emerald Ash Borer (Agrilus planipennis)
Native to eastern Russia, China, Japan, and Korea
Specialist invasive
Invasive throughout the northern parts of the Midwest and East coast of the USA and Canada
Larva eat at the woody tissue of Ash trees

20. Invasive species impacts (fungi)
At the end of the 1800s:
- American chestnut was found throughout much of the Eastern Deciduous Forest.
Chestnut was among the largest of eastern trees.
Pure stands were common
(> 80 % Basal Area in some stands)
Range of American chestnut
From: Paillet and Rutter (1989)

21. Photos from The Canadian Chestnut Council:
- In 1904, chestnuts in the New York area began exhibiting a previously unknown canker.
- This disease, caused by the fungal pathogen Cryphonectria parasitica, spread throughout the native range of the American chestnut.
- By 1960, chestnut had been rendered functionally extinct as a canopy tree throughout its native range.