Human Induced Population Decline Flashcards
What are the 5 ways humans induce population decline?
H: Habitat loss and Fragmentation
I: Invasive / Exotic Species
P: Pollution
P: People
O: Over-Exploitation
What is the Traditional View of Fragmentation and Fragmented Landscapes?
- Gap Formation
- Gap Enlargement
- Conversion of landscape matrix to anthropogenic habitat
What does HDE stand for?
Human Dominated Ecosystems
How does fragmentation of a landscape normally occur in MB?
Road construction or township grid systems
How are Gap Enlargements normally occurring in MB?
Edges are straight and unnatural and expansion of road systems.
What are Shredded Habitats?
- Remaining habitat in ribbons
- Small islands (untouched)
What are some impacts of linear features on a landscape? (7)
- Creates meta population
- Provides corridors for range of expansion of native and invasive species.
- Reduces availability of land base
- Population Sink
- Interfere with Breeding
- Displace Forest Interior Species
- Provide Increased Access to Humans and other Predators
What does increased density of people in rural landscapes lead to?
- Increased density of roads, buildings, and fences.
- Light pollution
- Domestication of wildlife
What are some impacts of Urbanization?
- Increased mortalities
- Fragmentation of habitat
-Wildlife loss
What does urbanization lead to? (3)
- Increase # of generalist species
- Loss of species
- Human Dominated Ecosystems (HDE)
True or False: Today, only half of the world’s original forest cover remains.
True.
What is an Alien / Exotic / Non-native species?
Organisms that have been deliberately or accidentally relocated by humans outside their natural, past or present distribution.
True or False: Exotic species are always invasive.
False, not always.
Define an invasive species:
The ability to spread and prosper in areas where the species has not occurred before and whose introduction or spread threatens the environment, economy, or society, including human health.
Define a Biological Invasion:
The spread of alien organisms into areas where they do not naturally occur.
Define a Naturalized Exotic:
Introduced species that have become established and are maintained by natural reproduction (not necessarily invasive).
What makes a species invasive? (3)
- High reproduction rates
- Disperse easily
- Lack of natural enemies
What makes a plant species invasive? (4)
- Early maturation
- Rapid growth
- Seed dormancy
- Parasitize other plants
Why should alien species be managed?
Because all areas on the globe with similar climates will contain a homogenized population of species.
What are an example of an exotic species?
Zebra Mussles