Biogeography 2 Flashcards
1
Q
Martín (2009)
A
- Are the IUCN standard home-range thresholds a good indicator
- Area of whole of Canaries is below range threshold for IUCN, all endemics are endangered, money has to go into monitoring, robs species that are actually endangered
- Need to distinguish between species that need action to prevent extinction and those that could be at risk simply because of their rarity but not current in decline
- Number of locations inhabited depends on minimum distance between locations
2
Q
Rabinowitz (1981)
A
- 7 forms of rarity
- Habitat breadth, geographic range, abundance
3
Q
Lennon et al (2001)
A
- The geographical structure of bird distribution
- Areas of species richness change with changing scales, cannot be divorced from one another
4
Q
Mckinney (2002)
A
- Do human activities increase species richness
- Do human activity induced alien species outnumbered extinct/threatened native species resulting in higher diversity at scale of US states?
- yes for plants. The higher the human density the more plants there are
- humans bring in plants for different purposes
- no for freshwater fishes
5
Q
Pautosso (2007)
A
- Scale dependence of the correlation between human pop and richness
- Human presence is generally negatively related to species richness locally, but the relationship is positive at coarse scales
- the broad-scale positive correlation between human presence and species richness suggests that people have preferentially settled and generally flourished in areas of high biodiversity and/or have contributed to it with species introductions and habitat diversification. The scale dependency of the correlation between people and biodiversity’s presence emphasizes the importance of the preservation of green areas in densely populated regions.
6
Q
Whittaker et al (2005)
A
- Conservation biogeography assessment and prospect
- species occupying large ranges tend to be more abundant throughout those ranges than range-restricted species
- A crucial distinction is that between (a) the geographical extent of a study system, being the space over which observations are made, e.g. a hillside, a state, a continent; and (b) the grain (focus) of the data, being the contiguous area over which a single observation is made, or at which data are aggregated for analysis, e.g. a light trap, 1 ha plot, or latitude–longitude grid cell
7
Q
Crooks & Soulé (1999)
A
- Mesopredator release
- Mammalian carnivores much more susceptible to extinction in fragmented habitats
- This can lead to rise of smaller carnivores (mesopredator release) that prey on birds, causing sever decline in bird numbers
- This is particularly devastating when the mesopredators are domestic cats
8
Q
Ladle (2009)
A
- Forecasting extinctions
- Extinction predictions important, but overestimating leads to ‘greenwashing’ accusations and underestimation leads to apathy
- All models have assumptions, need careful consideration of application
- Still provide useful information
- Different types of extinction have different agencies within conservation, ie. Local versus global extinction
9
Q
Laurance (2007)
A
- Have we overstated the tropical biodiversity crisis?
- Have been arguments that the rise of urban centers and the decline of rural areas of living will slow deforestation in the tropics and that the extinction crisis has been overstated
- Laurance argues this hypothesis understates the extinction crisis and that politician could latch onto this theory, so it must be seriously evaluated
10
Q
Lindenmayer and Fischer (2006)
A
- Tackling the habitat fragmentation panchreston
- ‘Habitat fragmentation’ used in so many varying instances that it has become a meaningless term
- Clearer themes might solve the panchreston problem, such as land cover and habitat and connectivity
11
Q
Triantis et al. (2010)
A
- Used historical deforestation data from the Azores to calculate an ecologicaly adjusted species area curve
- This SAC suggested that the extinction debt of the Azores was much higher than previously thought and urged swift conservation action (50% of arthropods)
- Corrects for inaccurate SAC’s
12
Q
Bloom et al. (2011)
A
- 40 year study of Red-shouldered hawks
- Most moved no more than 100k
- 3 were vagrants that moved 300-800k
- Opportunity for random colonizations
13
Q
Lindbladh et al. (2008)
A
-Fagus expansion seems to be coupled with anthropogenic disturbance circa 1600
14
Q
Henderson & Whittaker (1997)
A
- Galapagos
- Attractiveness to humans best predictor for invasive potential
- Cultivated species may tend to be more invasive, possibly because of their dissimilarity to native species
15
Q
Castro et al. (2007)
A
- Transit towards floristic homogenization on oceanic islands
- Exotic invasions and a low extinction rate of natives is making some oceanic island go through a very slow homogenization process
- The number of plant species doubled from 263 in pre-European flora to 531 species currently
- The frequency of plant species shared by two or more islands is higher in the post-European floras than prior to European contact, and the level of floristic similarity between islands increased slightly.
