Group ________________Name _____________
ICA 3 LANDSCAPE ECOLOGY + CONSERVATION BIOLOGY 2
1. What is landscape ecology? Study of relationship between spatial pattern and
ecological processes over a range of scales.
2. What are components of landscape structure?
A. size B. shape C. composition D. number E. position of patches
3. What ecological processes are affected by landscape structure?
A. flow of energy B. flow of matter C. movement of species
D. small population dynamics/genetics E. species interactions/community dynamics
4. What is meant by “The landscape is highly fragmented”.
A formerly continuous landscape has been cut into small pieces of the former habitat
each embedded in a new matrix.
What is meant by “edge effects”? Responses (usually negative) of
individuals/populations to conditions created from edges being created via
fragmentation.
5. Figure 1. Describe and explain the results. Cowbird parasitism of other species’ nests
decreased with increased distance from agricultural edge. The cowbirds prefer
disturbed open habitats and avoid deep interior of forest.
6. Figure 2. What is the question being addressed? Does fragmentation increase
biomass loss in edges relative to interior?
What is the result? From 0-4 yr post-fragmentation, % biomass lost increased in
edge plots and then stabilized. The control data are missing – from interior plots.
What data are missing before a conclusion can be reached?
7. Construct a sentence that incorporates: patch, mosaic, matrix.
Patches embedded in a contrasting matrix create a mosaic.
8. What is a problem for the owl because of habitat heterogeneity?
To migrate between suitable habitat patches requires passage across unfavorable
habitat. Subpopulations are separated and can’t expand.
9. Figure 3. Describe these population responses to habitat patchiness:
Metapopulation model: Movement occurs between subpopulations; quality of matrix
doesn’t affect movement, but arrangement of and distance between patches may.
Source-sink model: Source populations in high-quality patches produce excess
offspring, which disperse to less productive sink populations in less suitable habitat.
Landscape model: Same as metapopulation model, but affected by mosaic of different
habitat types that affect movement between patches.
10. What is a metapopulation? Set of discrete subpopulations divided by unsuitable
habitat with varying amounts of migration between patches.
11. What factors determine if a matrix is a barrier to movement?
A. Distance between subpopulations
B. Nature of intervening matrix habitat
C. Mobility of species
12. Figure 4.How is ‘genetic structure’ of a population affected by habitat heterogeneity?
Genetic differences arise between subpopulations due to lack of movement between
them.
13. Figure 5. On what factors does metapopulation dynamics depend?
A. birth and death within each subpopulation
B. migration between patches
C. colonization to form new subpopulations
D. extinction of existing subpopulations
What is the role of ‘connectivity’? It is a measure of the ability to move between
patches and maintaining cohesion of population.
14. Figure 6. Summarize two major results.
A. Area of island is greater for occupied then unoccupied patches.
B. Patch isolation covers a wide range of distances for unoccupied patches,
but no occupied patches occur more than 1.5 km from another patch.
15. What are ways in which randomness is expressed for small populations?
A. catastrophe strikes
B. the environment varies
C. stochastic (random sampling) processes occur; each can cause extinction.
16. Figure 7. Summarize two major results.
A. Probability of extinction increases with decreasing initial population size.
B. Probability of extinction increases over time.
17. Figure 8. Summarize two main results and provide a reason for each result.
A. Larger populations were less likely to become extinct.
B. More closely spaced populations were less likely to go extinct.
What traits enable a population to rescue a small population from extinction?
Being nearby; being large with an excess of offspring that are mobile.
18. What is the ‘rescue effect’? Immigration from a large to a small subpopulation
that keeps a declining subpopulation from inbreeding and/or going extinct.
Figure 9. How does it relate to a ‘source-sink’ landscape model
The large subpopulation is the source with excess offspring that move to the small
sink population.
CONSERVATION BIOLOGY 2
1. Distinguish between:
population-level: concerned with single-species preservation
habitat-level conservation: concerned with entire areas with diverse habitats and
hence high biodiverstiy
2. What are two traits of ‘biodiversity hotspots?
A. High number of species
B. High number of endemic species
What is an ‘endemic’ species? restricted to small geographic area (e.g. island)
3. What is the ‘evil quartet’ that causes species extinctions?
A. habitat destruction/fragmentation B. introduced species
C. overkill (overexploitation
D. chains of extinction
4. Figure 10. Summarize the main result. Animals are more likely to be absent from
small than large woodlots.
5. What problems does fragmentation cause?
A. reduced total area
B. reduced habitat heterogeneity
C. reduced connectivity
D. greater inter-fragment distance
E. can’t migrate with changing climate F. reduced interior/edge ratio (edge effects)
6. What principles govern Preserve Design: Large expanse of uniform habitat
A. Larger is better than smaller.
B. One large area is better than several small that sum to same size
C. Add corridors or ‘stepping stones’
D. Circular is better than elongate; circles have higher interior/edge ratio
7. Figure 11. Summarize the major result and explain it.
As size of island increases, proportion occupied increases.
8. SLOSS: Why is a larger preserve better than a smaller one?
A. Support more species by reducing chance of stochastic extinction.
B. Promote genetic diversity.
C. Bigger populations against disturbance.
D. Avoid ‘edge effects’.
E. Offer freedom to migrate without going outside of normal habitat.
9. Figure 12. Summarize two major results.
A. No movement occurs between patches with no corridors.
B. Movement decreases with increasing distance between patches with corridors.
10. What are advantages of corridors?
A. Increase immigration (increase # species; provide ‘rescue effect’; add genetic
diversity)
B. Increase foraging area for widespread species
C. Provide cover for escape from predator when moving.
D. Provide alternative refuges from large disturbances
E. Provide mix of habitats for species requiring them.
What are their disadvantages?
A. Risk the spread of disease, weeds, invasive species between patches
B. Disrupt local adaptations and cause outbreeding depression
11. What principles govern Preserve Design: Diverse habitat
A. Several small in different habitats better than one large in uniform habitat.
B. Plan for migration
How can migration be enhanced? Use corridors/stepping stones; bridge roads
and pipelines that impede movement.
12. What factors need to be considered to ensure good community structure in a
preserve?
A. Maintain top-down control of trophic abundances
B. Cascade effects may occur.
C. Can have chain of extinctions if species are highly inter-dependent
D. Preserve keystone species that maintain diversity/stability.
E. Vegetation structural (and plant species) diversity increases species diversity of
animals.
F. High diversity of plant species assures year-round supply of food for
greatest diversity of animals.
G. Maintain minimum viable population sizes (>500 individuals).