Karteikarten
CONSERVATION ECOLOGY
Karten in diesem Stapel (49)
- 1What is conservation? What are it two main goals?“Conservation biology seeks to integrate
evolutionary theory with environmental reality to predict how an animal/population/species
will react to future/current changes,
• Investigate human impacts on biodiversity
• Develop approaches to prevent biodiversity loss - 2What are the two patterns of extinction in the global record?BACKGROUND EXTINCTION = patterns
are the long pattern of ecosystem
change that leads to some
species going extinct
MASS EXTINCTION patterns are
catastrophic spikes of extinction
associated with sudden
widespread ecosystem change - 3Who monitors biodiversity? What are the IUCN endangered-level criteria?*E INTERNATIONAL UNION
OF CONSERVATION - 4What is the 6th mass extinction?What we are thought to be in right now.
Some estimates for current rates of extinction
-1 species per hour
-27000 species per year
-100 to 10000 times the background rate
*Loss in biodiversity is well connected to human appearance and growth - 5Explain loss of genetic diversity within a species.*Even when species do not go extinct their populations get smaller
-reduction in effective population size
-Smaller populations loss exclusive alleles, reduced genetic diversity
=more likely to go extinct. - 6Explain ecosystem loss.Positive correlation between community diversity and ecosystem quality.
- 7What are the benefits from ecosystems?SERVICES= Previously only goods given value however Ecosystem services encompass all the processes through which natural ecosystems and their species help
sustain human life ( operate at such a large
complexity they
cannot be replicated) - 8What are the scales of services?Global scale = Carbon sequestration, climate change
Landscape scale = Water purification, erosion control
Community scale = Crop pollination, pest control
• Field, plot or individual person scale = Local nutrients, disease and pest
preventions - 9Why should be preserve biodiversity?Moral obligation
Enjoyment
Utilitarianism= Reservoir for new medicinal compounds. Reservoir for resistance genes. Ecosystem services (pollination of crops, fisheries,
oxygen, water purification, etc) - 10What are the 4 main threats to diversity?•Habitat loss or degradation (including pollution)
• Introduced species (including disease)
• Overexploitation (harvesting or hunting)
• Climate change - 11Explain habitat loss.largest threat = 98% of land transformed to agricultural, 73% of species endangered/extinct
-Deforestation = demand for building material, wood, rubber, palm oil, soy, beef. Displaces native humans and huge loss of species.
-Fragmentation = large continuous area is reduced and divided into two or more isolated patches. ^ local and global extinction. - 12Explain habitat degradation.*Pollution = land pollution release of chemicals leave vast areas unusable for most organisms. Air pollution has wild scale effects leading to complex alterations. Water pollution eutrophication and dead zones.
*Pesticides = e.g DDT bio-accumulation and bio-magnification ( pesticides become more concentrated up food chain) - 13Explain impact of introduced species. give examples of UK introduced species*Problematic = Displace native species. Have fewer predators/pathogens. Disrupt ecosystem function. Reduce overall diversity. Transmit disease
*UK INVASIVE SPP = Crayfish plague – Aphanomyces astaci, Asian hornet, a potential threat to UK pollinators. Many Plant Pathogens - 14Explain impacts of over exploitation.*Taking of wild plants/animals at rates that exceed the ability to replace them.
*Large organisms with slow reproductive rates are particularly susceptible.
• Aquatic and terrestrial systems are
both susceptible
*Overfishing = tuna populations in N atlanta down 80%, by catch kills non target animals 25% waste - 15Explain impacts of climate change.*Species distributions are limited = energetic costs, resource availability, fitness under optimal conditions
*If climate changes
-range shifts, plastic response, adaptation, extinction.
*E.g = bumblebees, warm oceans reshaping fisheries - 16Explain the mechanisms of extinction in a single population*Extinction is certain if, in the long term, the mortality and emigration rates> than the birth and immigration rate.
*Mechanisms act by affecting the migration, mortality and birth rates. 3 main mechanisms
- Demographic uncertainty - Environmental uncertainty - Loss of genetic diversity
*Population size is critical to survival. - 17What are the genetic factors affecting a small population?•Genetic Drift
• Founder Effects
• Bottleneck Effects
• Inbreeding depression - 18Explain the bottleneck effect.*Bottleneck effects are due to a sudden reduction in populations size due to change in the environment
- resulting gene pool may no longer be reflective of the original gene pool
-If the population remains small, it may be further affected by genetic drift - 19Explain genetic drift.*Change in frequency of an allele in a population due to random sampling
-The effects are significant in small populations
-Genetic drift tends to increase the likelihood that alleles are loss, reducing genetic variation within population - 20What is the equation for effective population size.Ne = (4Nf x Nm) / (Nf + Nm)
Effective population size is the number of individuals in a population who contribute offspring to the next generation. - 21What is the founder effect?*Founder effects occur when a few individuals become isolated from the larger population to form a new one
-Allele frequencies in the small founder population can be different from those in the larger parent population - 22What is inbreeding depression?*The relative reduction in fitness of
inbred progeny in comparison to an equivalent outbred progeny.
-A reduction in the number of mating individuals increases inbreeding increasing the expression of deleterious traits (previously concealed), causing fitness reduction. - 23What is an extinction vortex?*Small populations are prone to loss of genetic diversity via inbreeding and genetic drift which leads to smaller populations and an extinction vortex
-loss of genetic variation needed to enable
evolution of responses to environmental change = Small populations and low genetic diversity always lead to extinction - 24Outline the case study of the prairie chicken.*Sudden bottle neck due to habitat destruction. = Surviving birds had low genetic variation and only 50% eggs hatched
*Scientists imported genetic variation by transplanting birds from larger populations
= The declining population rebounded, confirming the importance of genetic variation - 25What is meant by Minimum Viable Population?Minimum population size at which a species can sustain its numbers. The MVP depends on factors that affect a populations
chances of survival over a particular time, such as how many individuals might be killed in an accident or
environmental catastrophe
*A meaningful MVP requires determination of the effective population size which is based on the population’s breeding potential. - 26What ecological factors affect population persistence?*Unequal sex ratios,
* Population fluctuations (prey-predators)
*Whether or not generations overlap,
*Age structure - 27What are allee effects?*The Allee effect is a phenomenon in biology characterised by a correlation between population size or density and the mean individual fitness
-mate limitations, cooperative defence, cooperative feeding - 28What categories of species are vulnerable to extinction Species that only occur in threatened habitat types,
Species that are economically valuable to humans,
Species that do not have any/much experience of disturbance,
Species that have evolved in isolation within a limited community without human
contact,
Species that lack long distance dispersal mechanisms,
Species requiring large home ranges
Short-lived species,
Species with a low adult survival rate,
Species with low genetic variability,
Species with a low intrinsic growth rate, - 29What is a metapopulation? What does survival depend on?*A metapopulation is a group of populations that are separated by space but consist of the same species. (more populations better than one if size not compromised)
*Survival depends on
-Local population survival (as before)
-Unoccupied suitable habitat at suitable distances
-Sufficient migration - 30How does landscape structure affect species survival?*Patch size = affects movement between populations, average distance migrated decreases with ^ patch size. As patch size increased migration increased
*Habitat corridors = increase population success as allows gene flow - 31What is population viability analysis?Assesses the combined impact on extinction of *Deterministic factors = habitat loss, exploitation, pollution
*Stochastic events = demographic (natural fluctuations in r independent of environment) environmental (fluctuations in r due to environment) genetic stochastic, catastrophes - 32Analysis of Grizzly bear populations.Early long term study using population viability approach conducted in Yellowstone National Park (Shaffer, 1978)
• Models predicted that a population of 100 bears would have a 95% chance of surviving about 200 years if habitat was
sustainable
• Nowadays grizzly census population is about 400, but Ne is only about 100
because of low genetic diversity
• Introducing 2 bears/decade will maintain genetic variation - 33What is the 50/500 rule?*Proposed by Franken (1980) and Soule &
Wilcox (1980)
*suggests that a minimum population size of 50 was necessary to combat inbreeding and a minimum of 500 individuals was needed to reduce genetic drift
*Land argued that demographic stochastic is more important as by time populations are small enough for genetic diversity to matter they are doomed - 34What are the two perspective of management biology?POPULATION APPROACH = conserve individual species. More common in the past but still embedded, Individual knock-on effects & fluffy!
ECOSYSTEM/LANDSCAPE APPROACH = Greater emphasis in current and recent conservation biology. Can’t save one without all & land use as a service. Unwieldy harder to evaluate - 35What is an umbrella species?When habitat is preserved to meet the needs of an ‘umbrella species’, it helps preserve habitat for many
other species.
- Large species with huge area requirements
-Pretty ones to win public affection
-Keystone species - 36Explain species focused management.•Confirm the population is in decline
• Study the species’ natural history
• Develop hypotheses for all possible causes of decline
• Test hypotheses in order of likelihood (informal)
• Apply the results of the diagnosis to manage for recovery - 37What is captive breeding?*Objective is to breed in captivity to release when conditions are appropriate for wild survival
*The object is to preserve plants and germplasm that can be distributed when needed = Kew Gardens holds nearly 10% of the world’s known flora, disproportionately threatened species
= long term survival - 38What are protected areas?Biodiversity hot spots are relatively small areas that have a great concentration of endemic species and many endangered or
threatened species
• Biodiversity hot spots are often choices for nature reserves , but identifying them may be challenging
• Designated hot spots are often biased toward saving vertebrates and plants
• Hot spots will change with climate!!!! - 39Larger reserves vs Smaller reserves?• Large reserves support larger, far-ranging animals with lowdensity populations that require extensive habitats
• Smaller reserves may be easier to achieve and may slow disease spread in weak populations
• Easier to manage small reserves
• Disturbance is functional! Reserves must accommodate it and this makes larger reserves more preferred. - 40What qualities make a better reserve?*Large reserves better than smaller ones
*Single large reserve better than many small
*Reserves closer together better than reserves far apart
*Circular reserves better than thin ones
*Connected by corridor are the best. - 41What are zoned reserves?Zoned reserve models recognize that conservation often involves working in landscapes that are largely human dominated
• A zoned reserve includes relatively undisturbed areas and the modified areas around them (buffer
zones)
• Long term protection of habitats depends on the economic health of the society in which it is embedded
• Marine reserves off limits to fishing - 42What benefits do marine reserves show?Marine reserves are behind.
However they show improvements inside their boundaries
-increased abundance of species
-larger individuals
-greater diversity
and outside
-spill over from reserves to non reserves. - 43What is the Lundy Marine reserve?Britain's first marine protected area - reef habitats and associated species
*Rapid increase in abundance and size of lobsters
*Spill over of lobsters into adjacent area - 44What are treaties?Cannot effectively dictate, but countries have agreements. These can be powerful tools in the conservation biology kit.
• CITES prepared in 1973 – bans trade and transport of endangered plants and animals or products derived from them
• Convention on Biological Diversity (CBD), from Rio conference in 1992, aims to:
• Conserve biodiversity
• Use biodiversity sustainably
• Ensure fair distribution of its benefits
• Has led to national and regional biodiversity action plans (BAPS in UK) - 45When should we interfere? Outline the small population approach and the declining population approach.SPA= Populations should be protected once they are too small. Usually associated with a genetic approach
DPA = Populations should be protected once they are consistently declining in size. Usually associated with an ecological approach - 46What are biodiversity hotspots?30% of all bird species are located in hot spots (~ 2% of Earth’s Land surface);
16% of all plant species are located in 18 hot spots (~0.5%)
• No coincidence of hot spots for different groups of organisms
• Focus on maximizing endemic or generalists? - 47What is a conflict of interest?The approach required to protect a species might conflict with an
alternative profitable use of land
- spotted own protection conflicts with use of land for timber
-Lower snake river dam to be removed to protect salmon - 48What are the scenarios considered by MEA?
- 49What scenarios show improvement?*Global orchestration = improvement in provisioning
*Order from strength = no improvement
*Adapting mosaic = improvement in all
*Techno garden = improvement in provisioning and regulating
Informationen
- Beschreibung
- Ecology and evolution 2 Karteikarten am CONSERVATION ECOLOGY, erstellt von Yasmin Beer am 20/05/2018.
- Erstellt von
- Yasmin Beer
- Aufrufe
- 1
- Bewertung