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ESS TOPIC 3 - Coggle Diagram
ESS TOPIC 3
Topic 3.4: Conservation of biodiversity
Habitat-based conservation:
Designing protected areas:
How large should it be?
One large or many smaller?
How many individuals need to be protected?
What is the best shape?
How close should reserves be to one another?
Should they be joined by corridors?
In-situ:
+ves: not moving animals
-ves: at risk of poaching etc
Ex-situ:
+ves: protection
-ves:
Species based conservation:
Botanical gardens and seed banks
Kew Gardens (in London) is the largest botanical garden in the world; it contains 25000 plant species (10% of the world’s total)
Seed banks are where seeds are stored, frozen and dry, for many years.
Global Seed Vault in Svalbard – secured seed bank, to act as an insurance against loss of other seed banks. No power needed
Strengths:
Preserves the genetic code of various plant species
Insurance policy against extinction
Can interbreed/hybridize seeds with heirloom varieties
Weaknesses:
How reliable is storage over long term?
Impossible to preserve every species on earth
Keystone species:
Critical role in maintaining the structure of the ecosystem it lives in.
Disappearance of this species could cause the disappearance of many others.
If conservation is to be successful these species must be identified.
Often engineers (e.g. beavers) that create habitats or small predators (e.g. sea otters) that keep herbivore numbers low enough that producers can survive.
Captive breeding and zoos:
The leaders of countries often showed their power by keeping a variety of exotic beasts, known as Royal menageries.
Heads of state would gift each other animals.
First zoos were when these were opened to the public
Since then zoos and aquaria have had to justify their existence.
This usually takes the form of captive breeding and funding conservation alongside education
Weaknesses:
Animals lose natural instincts
Can severely restricts/ limits gene pool
Difficult to re-introduce to the wild
Animal has become dependent on humans for survival
Habitat may have been destroyed or altered beyond animals ability to adapt to it
may not be accepted into social hierarchy of wild populations
Strengths:
Serves as a living store of animal DNA
High level monitoring and control (more than possible in the wild)
Prevents total extinction of species
Flagship species:
Charismatic, recognisable and popular.
Not necessarily ecologically important.
But attract funding for areas that need conservation efforts.
Umbrella species
Disadvantages of naming flagship species:
Takes priority over others (even if it is not the most in need).
If they become extinct the message is we have failed.
They may be in conflict with the local peoples, e.g. man-eating tigers
CITES:
The Convention on International Trade in Endangered Species of Wild Fauna and Flora.
An agreement between governments to address the problem of wildlife trade.
Governments must sign up voluntarily and create their own national laws.
Has generally been very effective, however little incentive for governments to comply
Animals are classified according to how threatened they are by international trade.
Appendix I – cannot be traded internationally as they are threatened with extinction.
Appendix II – international trade but within strict regulations ensuring its sustainability.
Appendix III – included at the request of a country which needs the cooperation of other countries to help prevent illegal exploitation
Strengths:
Voluntary
Locally enforceable where the poaching/trade may be happening
Reduces trade in animal parts
Good examples of monitoring species' status
Weaknesses:
If not enforced, ni change in species' status reality
no international body to enforce on national territory
Voluntary
Conservation Milestones
1992 – Rio Earth Summit – Agenda 21 (sustainable development agenda):
Conservation of biological variation
Sustainable use of its components
Equitable sharing of the benefits arising out of the utilisation of genetic resources
2000 – UN Millennium Summit: Millennium Development Goals. World leaders agreed on set of time bound and measurable goals. Many issues including poverty/hunger/gender equality.
2005 – World Summit, New York. Outlined global priorities and recommended each country prepare a national strategy for the conservation of natural resources
2013 – Rio+20. How to build a green economy. Resulted in non-binding paper “The future we want”
Political Influence:
IGO and NGO:
Some countries have more power than others.
Biodiversity is not equally spread among all countries.
Countries can be fined/shunned for breaking international rules
NGO:
Varies greatly depending on reputation
Often relies on disruptive/embarrassment techniques to cause change
Financial resources:
IGO and GO:
Potentially very large budgets. (Highly variable)
Funded by national budgets (taxes)
NGO:
Manage publicly owned lands.
Private donations.
Can be funded by companies, governments or political parties (however some explicitly refuse this)
Diplomatic constraints:
IGO and GO:
Considerable - often hindered by political disagreement (different cultural opinions and motives)
Decisions can be politically driven rather than by best conservation strategy. E.g. voting in the IWC
NGO:
Generally unaffected by political constraints
Can even include illegal activity.
Driven by what is best for conservation – can lead to extreme actions
Speed of response
IGO and GO:
Considered and slow (bureaucratic)
May go against public opinion so many views need to be considered
NGO:
Can be rapid.
Member only join if they share opinions, so little deliberation.
Little consideration of the status quo
Use of media
IGO and GO:
Works alongside official media outlets
Statements written by officers and clerks
NGO:
Graphic/shocking footage to gain media attention.
Mobilise public protests to attract attention.
Effective use of social media to spread message.
Sabotage events with high media coverage
Conservation organisations:
IGOs, GOs, NGOs
Intergovernmental organisations
E.g the UN, IPCC
Governmental organisations
E.g Environment agency
Non-governmental organisations
E.g. Friends of the Earth
Ethical arguments:
Usually very broad.
Rely on people believing these species have an intrinsic value or taking a utilitarian approach.
Intrinsic value – the value a species has within its own right (as opposed to the value it can give).
Utilitarianism – taking the best moral action that maximises happiness/minimises suffering to sentient entities.
Why conserve biodiversity?
Economic
Ecological
Social
Aesthetic
Ethical
Topic 3.3: Threats to Biodiversity
Factors that makes species extinct:
Narrow geographical range: The Golden Lion Tamarin( Case studies)
Small population size (low genetic diversity): Low genetic diversity
Less variation so less resilient to change
Low population densities and large territories: Reduces chance of individuals meeting for reproduction.
Requires very large area to support few organisms
Few populations: If there is only one population of a species then that is their only chance of survival
A large body:
Usually large range, low population densities and need lots of food.
Compete with humans for food.
Hunting trophies.
Danger to humans
Low reproductive potential: Reproducing slowly and infrequently means populations take a long time to recover.
Albatrosses produce one egg per pair per year and take several years to become fecund
Seasonal migrants:
Long hazardous journeys.
Reliant on multiple habitats.
Many salmon species swim upriver to spawn
Poor dispersers:
Species that cannot easily move to new habitats.
Plants rely on seed dispersal meaning they can die out before it can move.
Non-flying animals.
Flightless birds of New Zealand
Specialised feeders or niche requirements: Single food source can be destroyed, meaning you have no food.
Koala bear and eucalyptus
Edible to humans and herding together: Overhunting or harvesting can eradicate species very quickly, especially if the species lives in large groups.
In around 40 (or so) years 60million bison were hunted to just a few hundred
Island organisms:
Tend to be small
Islands have a high degree of endemic species (only found in that location)
Low genetic diversity
At risk of introduction of non-native species
Prominent predator
The IUCN Red List:
Extinct (EX) – beyond reasonable doubt that the species is no longer extant.
Extinct in the wild (EW) – survives only in captivity, cultivation and/or outside native range, as presumed after exhaustive surveys.
Critically endangered (CR) – in a particularly and extremely critical state.
Endangered (EN) – very high risk of extinction in the wild, meets any of criteria A to E for Endangered.
Vulnerable (VU) – meets one of the 5 red list criteria and thus considered to be at high risk of unnatural (human-caused) extinction without further human intervention.
Near threatened (NT) – close to being endangered in the near future.
Least concern (LC) – unlikely to become endangered or extinct in the near future.
Data deficient (DD)
Not evaluated (NE)
Factors that lead to the loss of biodiversity:
Habitat destruction:
Invasive species
Pollution
Overharvesting and hunting
Factors that maintain biodiversity:
Complexity of ecosystem – complex food webs.
Stage of succession – later stages stable.
Limiting factors – abiotic factors.
Inertia – ability to withstand disruptive force
Extinction rates:
Due to our lack of knowledge of how many species there actually are it makes it very hard to estimate extinction rates.
100 species per million species per year.
1000 times the background rate.
3 species per hour.
Humans are responsible
Estimates vary hugely:
Estimates vary from 7 to up to 100 million.
Mathematical models used to calculate these values.
However, we really cannot estimate how bad we are at counting certain groups.
Lack of financial resources
How many species are there? Estimates vary greatly but a conservative estimate is 7 million (excluding bacteria)
Topic 3.2: Origins of Biodiversity
Mass extinctions:
Tectonic plate movement.
Super-volcanic eruption.
Climatic changes (drought and ice ages).
Meteorite impact.
Speciation – the formation of new species via the process of evolution:
New species arise when populations of a species become isolated and evolve differently from other populations.
Natural selection contributes to the evolution of biodiversity over time:
Evolution does not occur over one generation.
This is why many find it hard to accept evolution.
It takes many generations for large changes to be seen.
Natural selection occurs through the following mechanisms:
Mutation creates variation
Unfavourable mutations selected against
Reproduction and mutation occur
Favourable mutations more likely to survive and reproduce
In order for evolution to occur three things are necessary:
Variation – every individual is unique, you have unique set of DNA which means that you differ from others of the same species.
Natural Selection – various factors make certain individuals fitter. This means they have more chance of having offspring.
Heredity – the characteristics that made you fitter need to be coded in your DNA, and need to passed onto your offspring
What is the point?
Biologically your purpose (and the purpose of all living things) is to pass your DNA onto the next generation.
So the more offspring you have the more DNA you have passed on.
We measure this as Darwinian fitness or just fitness.
So the fitter you are the more offspring you have
Topic 3.1: Introduction to biodiversity
Hot spots:
Biodiversity hotspot – a region with a high level of biodiversity that is under threat from human activities.
Tend to be near tropics
There are regions in most biomes
70% loss already
1500 endemic plant species
Critics say that hotspots:
Focus on vascular plants and ignore animals.
Do not represent total species diversity or richness.
Focus on places that have already lost habitat, not those that are losing it.
Do not consider genetic diversity.
Do not consider the value of services: e.g. water resources.
Diversity Indices
Simpson’s Diversity Index
When comparing similar communities low diversity could indicate pollution, eutrophication or recent colonization.
Important to repeat investigations over a period of time:
Is biodiversity increasing or decreasing.
Are conservation efforts needed?
Biodiversity: The variety of forms of life on Earth
Genetic diversity: Range of genetic material present in a species or population
Species diversity:
Product of two variables:
Species richness (number of species)
Species evenness (relative proportions)
Habitat diversity: The range of different habitats in an ecosystem.
E.g. Fresh Water, Woodland, Grassland, Hills..
Case Studies:
DANUM VALLEY CONSERVATION AREA (DVCA):
Malaysian Borneo
Was under major threat from commercial logging, until the late 1980’s
There was a collaboration in research between Yayasan Sabah (logging company) and the Royal Society in the UK
Success:
Corridors to other conservation areas within the island, allowed for the movement of animals
Hotels, ecotourism, both helped the local economy
Employment and educational opportunities for local community
High international profile and key research held over long period of time, one of the most important conservation areas in the world
Refuge for many endangered species, eg: Sumatran Rhino
Failures:
Oil palm plantations near protected area could discourage ecotourism, as tourists are not keen on seeing the plants close to protected area
Presence of people near protected area could encourage poaching or illegal logging activity
Conflict between aims of commercial industry and aims of conservation project
Change in leadership may lead to changes in aims
ELEPHANT BIRD OF MADAGASCAR: (EXTINCT)
Extinct
Endemic to the island of Madagascar
The arrival of humans lead to their extinction (1,000 years ago)
The forest the birds relied on was cleared and burnt, 80% of natural vegetation was lost, the eggs of the birds were also eaten by humans
Ecological role was herbivore
The loss of the species has left more vegetation for other species such as lemurs
GOLDEN LION TAMARIN MONKEY: (ENDANGERED)
Critically Endangered
Conservation status has been improved by intervention
Under threat because:
90% of their original forest habitat in Brazil has been cut down
The remaining habitat is small and fragmented
The species is only found in one small area of Brazil, especially prone to extinction
Were killed as were believed to spread human diseases
Ecological role is omnivore, they eat fruits, insects and small lizards
Loss of species would mean the following:
Seed dispersal of plants that have fruits eaten by the monkeys would be affected
Species at lower trophic levels would become more numerous
Shortened food chains would produce changes in other trophic levels and produce imbalances in the forest food web.
Being restored through captive breeding programmes and wildlife reserves