Conservation Bio Midterm Flashcards
Why is their a need for Conservation Biology?
- We’re experiencing an unprecedented loss of biodiversity
- The current (sixth) extinction event is undeniably being caused by a rapid increase in human abundance
- The current extinction event threatens humans
Compare Conservation Biology and Ecological Restoration
Conservation Biology: addresses the biology of species, communities, and ecosystems that are perturbed (directy/indirectly) by human activities or other agents
Ecological Restoration: The practice of assisting the recovery of an ecosystem that has been degraded, damaged, or destroyed
What are the three types of diversity that Conservation Bio deals with conserving?
- Genetic diversity
- Species diversity
- Ecosystem diversity
Which type of biodiversity do most discussions focus on?
Species diversity
What are some reasons for caring about biodiversity?
Ecological reasons (2)
1. Biodiversity increases stability
2. Biodiversity is important to many ecosystem services (for which human-made substitutes are either not available or affordable)
Financial reasons
1. Each species entail potential solutions to human needs (medical uses)
Cultural reasons
1. Belief that all species are entitled to life
2. E.O. Wilson –> humans have an innate connection to all life –> biophilia
What are the goals (3) of Conservation Biology?
- Document the amount/distribution of biodiversity
- Conduct research that focuses on topics like the importance of biodiversity
- Develop practical techniques to:
i. Prevent species extinctions
ii. Maintain genetic diversity and evolutionary processes
iii. Protect/restore ecosystems and their functions
What are some characteristics of Conservation Biology?
- A reactive science (crisis discipline)
- An inexact science
i. provides probablistic answers
ii. answers that err on the side of caution - A value-laden science (rigorous)
- A science with an evolutionary time scale
- A science of eternal vigilance
- A synthetic science (several individual disciplines)
What are some methods for protecting biodiversity?
- Advocacy
- Legislation (SARA)
- Executive order
- Financial incentives
- Management
The Canadian SARA and US ESA protect specific organisms, what are the advantages/disadvantages of this?
Advantage: SARA and ESA mandate that critical habitat be identified/protected, so conservation for a single species can benefit others
Disadvantage: Protecting entire ecosystems is critical to the longterm success of conservation
What three categories fall under the focal-species approach?
- Umbrella species - species that require large areas of habitat, so protecting it will protect others
- Flagship species - a charismatic large vertebrate that can garner public support for conservation
- Keystone species - species that have a large impact on the functioning of the ecosystem (relative to their body size??)
Why does ER focus on restoring native species diversity?
- It plays a large role in supporting ecosystem functions
- It is relatively easy to measure
What are the three levels/scales of species diversity?
- Alpha diversity - diversity in ONE site/ecosystem
- Beta diversity - usually measured for two sites
- Gamma diversity - landscape-scale diversity, or diversity across all sites in a region
What are the two fundamental components of diversity?
Species richness and evenness
What are the three most commonly used diversity measures?
- Simpson’s Index of Diversity
- Shannon-Wiener Index of Diversity
- Pielou’s Evenness Index
What types of indeces are Simpson’s and Shannon-Wiener? What are they best used for?
Simpson’s –> Type II index, which is most sensitive to changes in abundance species
Shannon-Wiener –> Type 1 index, most sensitive to changes in rare species
What is an example of a community similarity index?
Jaccard Index of Community Similarity, compares species composition between communities.
What types of diversity should ER focus on?
ER should focus on maximizing Beta and Gamma diversity, so high priority sites for ER are those with low community similarity
Which objectives should be monitored for ER?
- Those that are easy to measure
- Those that are strongly linked to ecological health
- Where relevant, those of greatest importance to stakeholders/funders
What are some variables (indicators) that are correlated with ecosystem health?
- Diversity of native species
- Abundance of native focal species
- Presence/abundance of overabundant species
- Water quality
- Hydrologic processes
- Soil characteristics
- Toxicants
- Pollutant-intolerant inverts (EPT)
To gauge success of restoration sites, you should compare current values of indicators to what? (3)
- Control sites
- Reference sites
- Baseline data
What three factors make selecting a reference site difficult?
1.Un-impacted sites can vary greatly in terms of succession
2. Un-impacted sites vary greatly within a ‘natural range of variability’
3. The pervasiveness of human impacts means that finding truly un-impacted sites is difficult
What is a way to minimize complications in selecting appropriate reference site?
- Select a reference site as close as possible to the restoration site (fewer differences in conditions)
Compare simple random sampling and systematic sampling, how would you navigate the drawbacks of each?
Simple random sampling - every possible sampling unit has an equal likelihood of being selected (Not biased but poor coverage)
Systematic sampling - sampling units are selected at regular intervals (Biased if used alone, coverage is as good as you make it)
Most sampling entails using a combination of these sampling designs
What is stratified sampling?
Dividing the sampling area into strata, among which the population is known to differ, and then sampling seperately within each stratum
What are four commonly used measures of abundance?
- Presence/not detected
- Relative abundance
- Density
- Total abundance
For effective monitoring, what key items should be included in your monitoring plan?
- Identify what objectives will be monitored
- Baseline data (control/reference sites, reference conditions)
- Monitoring locations (where will this occur)
- Techniques and materials used
- If using sampling, which items would you describe? (sampling unit, sampling size, etc.)
- Schedule of monitoring for each indicator variable
What are the six threats to biodiversity?
- Overharvest
- Introduced species
- Habitat degradation
- Indirect effects/secondary extinctions
- Pollution
- Rising CO2 levels
Compare fishing DOWN the food web with fishing THROUGH the food web
Fishing down the food web - Fisheries depleting large predatory fish, then shifting focus to increasingly smaller fish/inverts
Fishing through the food web - Fisheries adding low tropich level species to their harvests w/o reducing catches of upper trophic levels
How can invasive species alter their adopted community?
- By preying on native species
- By outcompeting native species for resources
- By altering native physical conditions, or ecological processes
What are the three forms of habitat degradation? Why is it important to distinguish between them?
- Habitat loss
- Habitat fragmentation
- Habitat alteration
It’s important to distinguish between these forms as they can have different effects on species/ecosystem processes
What is an example of an indirect effect/secondary extinction?
Trapping leading to declines in beavers which are keystone species, resulting in many changes to wetlands across NA
What does the term ‘coextinction’ mean?
Originally referred to the extinction of a parasite after extinction of its host.
Now more generally describes the decline/extinction of one species affecting others
Compare biomagnification with bioaccumulation
Biomagnification: concentrations of toxicants increase with trophic level (concern for species at higher trophic levels e.g., killer whales)
Bioaccumulation: concentrations of toxicants increase within a trophic level
Why is it difficult to understand where toxic thresholds occur in animal?
- We lack controlled dosing experiments
- Effects of a toxicant can vary due to age, sex, and condition
- Effects of a toxicant can vary due to other toxicants
How is it that some contaminants are spread to seemingly pristine areas?
Air and water currents
