Download module 4 4.2.1 maintaining biodiversity student version

Module 4 - 4.2.1 Maintaining
Biodiversity
By Ms Cullen
What human activities do you
think reduce biodiversity?
Brainstorm
How is climate change affecting
biodiversity?
• Adaptation – most species are adapted to
survive a particular climate
• Migration – Hornets previously only found in
Southern England are now found in the
Midlands.
• Extinction – Panama 1998
How is climate change affecting
agriculture?
• How will increased levels of CO2 and increased
temperatures affect crop yield?
• How will increased transpiration rates &
changes in precipitation affect crops?
• How will rising sea levels affect agriculture?
• Will it matter that we have selectively bred
many of our crops and livestock?
• What could be the result of extreme weather
systems?
How is climate change affecting
disease?
• As new crops are grown in new areas they
could encounter new pests and diseases.
• As areas become warmer and wetter some
diseases may spread eg the anopheles
mosquito which is the host for the disease
malaria may well migrate.
• Warm, wet conditions can also increase the
spread of fungal diseases.
• An increased spread of diseases could lead to
a reduction in biodiversity.
Why do you think we need to
conserve species?
Brainstorm
Economic reasons
Ecosystems perform processes that are valuable
to humans –
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Ecological Reasons
Organisms have complex relationships with
their environments. The loss of just one
species can have a major effect –
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Aesthetic Reasons
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Ethical Reasons
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What is a keystone species?
A keystone species is a species that has a
disproportionately large effect on its
environment relative to its abundance.
They fit into 3 categories:
1. Predators eg sea otters which maintain sea
kelp forests by consuming sea urchins.
What is a keystone species?
2. Mutualists eg the cassowary in New Guinea
and Australia, many seeds will not germinate
until they have been through their gut!
3. Engineers eg elephants which destroy trees,
making room for more plant species and
dispersing seeds in their dung. Also the prairie
dog in North America – find out why!
So now we know why we should
conserve species............
.........how do we do it?
In situ conservation of endangered
species
• Generally this is the best method of
conservation, preserving a species where it
naturally lives.
• This involves protecting the habitat eg nature
reserves or national parks. In these areas
habitats can be protected by restricting urban
& industrial development and farming.
• Or preventing human activity from
endangering the species further eg people
who live, work and holiday in the habitat.
In situ conservation of endangered
species
• A Marine Conservation Zone (MCZ) is a type of
marine nature reserve in the UK.
• They are established under law since 2009 and are
areas designated with the aim to protect nationally
important, rare or threatened habitats and species.
• About 20% of UK waters now have some protection.
• Local ones include; Poole rocks, South Dorset and
The Needles on the IOW.
In situ conservation of endangered
species
• Controlling or preventing the introduction of
other species that may threaten local species
diversity.
• Protecting habitats eg coppicing woodland,
maintaining water levels in wetland areas.
• Restoring damaged areas eg after an oil spill.
• Promoting particular species by providing
nesting sites or protecting food sources.
• Giving legal protection to endangered species
(eg CITES)
Disadvantages of in situ
conservation
• The disadvantages are that often the
endangered species lives in an area where
humans are also struggling for survival and
this can cause conflict between the needs of
local human populations and the threatened
species.
• Perhaps the best way to overcome this is by
getting local people involved in conservation
projects eg giving people jobs within the
conservation project.
Disadvantages of in situ
conservation
• Every time an in situ
conservation programme
takes place it is important to
assess the potential affects
of that programme on other
species. eg a large elephant
population can damage
vegetation, which can reduce
the stability of the habitat
for other species.
Disadvantages of in situ conservation
• In some cases the difficulties are so
great that it is unlikely that in situ
conservation will be successful.
• This is particularly true when there is so
little suitable habitat left to maintain a
viable population of the endangered
species – sometimes this is temporary in
the case of the scimitar-horned Oryx,
but unfortunately in some cases it may
be more permanent – for example tigers
may be impossible to conserve in situ as
a result of hunting and habitat loss.
ex situ conservation of endangered species
• While the most efficient and effective means of conserving biodiversity is the
management of biological communities in situ, many species require additional
support.
• Working with ex situ populations, directly manages populations of endangered
species through cooperative captive breeding programmes, providing technical
support to build wider capacity for this work and undertaking research to
inform population management.
• Studies of populations in captivity can yield important information to support
broader conservation goals. Ex situ research focuses on key species and
principles of population management to meet broader conservation goals. This
includes understanding the influence of both large (population level) and small
scale (husbandry) management decisions on the success of captive breeding
programmes and the ability to maintain these small populations over time.
Disadvantages of ex situ
conservation
• Only a small number of individuals can be
cared for.
• Can be difficult and expensive to create and
maintain a suitable environment for breeding.
• Ex situ is less successful than in situ
conservation, some species do not breed
successfully in captivity or can not adapt to
their new environment.
Advantages of ex situ conservation
• The environment can be controlled, therefore
factors like predation and hunting can be
more easily controlled.
• Can be used as a method to reintroduce a
species that has become extinct in an area.
http://www.youtube.com/watch?v=I-7wLdKjf2Y
The Role of Botanic Gardens
• These are important in the conservation of
endangered plant species.
• Seeds or cuttings can be collected from the wild and
then used to build a population of plants. These can
then in the future be used to repopulate their natural
habitats.
• The Millenium Seed Bank project began in 2000, its
aim is to collect and store 10% of the world’s plant
species, so that even if they become extinct in the
future, there will still be seeds available which can be
grown into new plants.
The Role of Botanic Gardens
• If possible seeds are collected from several
different sites, as this ensures a range of genetic
variation.
• Some seeds are easy to store but some need
special conditions, others can not be stored as
seeds and will have to be kept as adult plants.
• Stored seeds will have to be grown into plants so
that new seeds can be collected, as most seeds
will not survive for too many years.
• Botanical gardens are also important for
research, display and education.
The importance of genetic
biodiversity
• Within a species there is a very little variation
within their DNA.
• All individuals within a species share the same
genes, but may have different versions of the
same genes, known as alleles.
• The more alleles there are in a populations of
a species, the greater their gene pool and the
more genetically biodiverse that population is.
• Species with greater genetic biodiversity are
more likely to adapt and survive.
Remember Evolution occurs via
Natural selection:
• Variation with individuals.
• Selection Pressures eg predation, competition, disease.
• Best adapted individuals survive, breed and pass on
beneficial alleles.
• This results in a greater proportion of the next
generation having the beneficial allele.
• They in turn survive, breed and pass on the beneficial
allele.
• The frequency of the beneficial allele within the gene
pool will increase.
• This process is called natural selection.
Factors which increase number of
alleles will increase genetic
biodiversity
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Factors which decrease number of alleles
will decrease genetic biodiversity
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Measuring genetic biodiversity –
Genetic Polymorphism
• Alleles of the same gene are found in the
same position or loci on a chromosome.
• Polymorphism is when a locus has 2 or more
alleles – blood groups is an example of this; IA,
IB and IO are all possible alleles.
• If you work out how many chromosomes in an
organism have more than one possible allele
(ie polymorphism) this will give a measure of
genetic diversity.
Measuring genetic biodiversity –
Genetic Polymorphism
• This can be done using the following formula:
Proportion of polymorphic gene loci =
number of polymorphic gene loci
total number of loci
• These calculation are used to monitor the
genetic diversity of populations over time and
are particularly important for monitoring
genetic diversity in breeding programmes in
zoos, which are closely managed to maximise
genetic diversity.
Measuring genetic biodiversity –
Genetic Polymorphism
Example:
If 100 genes in a population are sampled and 34
are polymorphic then proportion of
polymorphic gene loci =
34/100 = 0.34
This may be expressed as a % in this case 34%
The higher the proportion of polymorphic gene
loci the more biodiverse the population.
Look at the worked example on P.277 of
Kerboodle.
So how can we conserve
biodiversity?
International cooperation
CITES
• Convention in International Trade in
Endangered Species of Wild Flora and fauna.
• Set up in 1973, 145 countries signed an
agreement which controls the trade in
endangered species and products from them.
• More countries have joined since.
http://www.cites.org/
CITES
Species are assigned to one of three appendicies:
- Appendix I species that are considered to be most
endangered and threatened with extinction, therefore trade is
prohibited (exceptions may be made for captive breeding
programmes).
- Appendix II these species are not necessarily threatened with
extinction, but may become so if trade is not controlled. Trade
is only granted if an export permit is provided by the country
from which the organism is taken.
- Appendix III includes species where there is regulated trade.
Permits are required to import and export these species and
they are more likely to be granted then species in Appendix II.
CITES
• These species lists are constantly reviewed and
increasing.
• CITES also works to raise awareness of threats to
biodiversity through education.
• A disadvantage of CITES is the illegal trade that
occurs due to the species fetching high prices.
• When it is announced that a species will go on the
list, during the time between the announcement and
the law being passed trade in that species will often
increase rapidly.
IUCN Red List
• The International Union for the Conservation of
Nature and Natural Resources.
• The IUCN Red List of Threatened Species™ provides
taxonomic, conservation status and distribution
information on plants and animals that have been
globally evaluated using the IUCN redlist categories.
• The main purpose of the IUCN Red List is to
catalogue and highlight those plants and animals
that are facing a higher risk of global extinction (i.e.
those listed as Critically Endangered, Endangered
and Vulnerable).
http://www.iucnredlist.org/
IUCN Red List
The IUCN Red List also includes information on:
• plants and animals that are categorized as
Extinct or Extinct in the Wild
• species that cannot be evaluated because of
insufficient information (i.e., are Data
Deficient)
• plants and animals that are either close to
meeting the threatened thresholds or that
would be threatened were it not for an
ongoing species-specific conservation
programme (i.e., are Near Threatened).
Rio Convention on Biodiversity
• In 1992 world leaders attended the Earth
Summit in Rio de Janeiro, Brazil, to discuss the
sustainable uses of the Earth’s resources.
• Out of this meeting came the Convention on
Biological Diversity (CBD), which was signed by
157 countries agreeing to protect their
countries biodiversity.
• In 2007 their were 190 countries signed up.
http://www.un.org/geninfo/bp/enviro.html
Impact of the Rio Summit in the UK
• In 1994 the Department of the Environment set out
an action plan to maintain biodiversity in the UK.
• The plan included objectives for conserving species
and their habitats.
• Local Biodiversity Action Plans were drawn up for all
parts of UK and these are constantly revised.
• SSSIs (Sites of Special Scientific Interest) were
identified and protected either as a result of the
species present there or habitats that they provide.
Impact of the Rio Summit in the UK
• Recently, it has been realised that all areas
need to be protected.
• Grants are given to farmers to maintain
hedges, create ponds or leave a margin
around arable fields.
• Industries are encouraged to create and
maintain ‘wild’ areas on their sites.
• Gardens are an important havens for wildlife.
Impact of the Rio Summit in the UK
• On 4th - 6th June 2012, the UN Conference on
Sustainable Development (UNCSD) or 'Rio+20' took
place in Rio de Janeiro.
• It is also referred to as the Rio+20 Earth Summit, due
to the initial conference held in Rio in 1992.
• The objectives of the Summit were: to secure
renewed political commitment to sustainable
development; to assess progress towards goals for
sustainable development and to address new
challenges.
• The Summit also focused on the green economy and
sustainable development.
Local Conservation
Countryside Stewardship Scheme
(CSS)
The UK government provides financial incentives
for farmers, woodland owners, foresters and
other land managers to look after their
environment through activities such as:
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conserving and restoring wildlife habitats
flood risk management
woodland creation and management
reducing widespread water pollution from agriculture
keeping the character of the countryside
preserving features important to the history of the rural landscape
encouraging educational access
EIA
• Environmental Impact Assessment (EIA) has to
be submitted every time a new development
is planned eg housing, roads, sewage works
etc
• An EIA also has to be submitted if significant
alterations are to be made to existing
developments.
• EIAs provide a full assessment of the effect of
a development on the species present in the
area.
EIA
• Environmental Consultants will carry out EIAs.
• If there are any species present that are
protected eg great crested newts or bats, or if
the development is thought to harm the
biodiversity, then the developer must put in
place measures to prevent this.
• This can be very expensive and the developer
is liable for it, therefore it is in the developers
interest to employ consultants who have a
record of not finding too many potential
problems!
Heathrow Terminal 5 EIA
During the construction
of Terminal 5 at
Heathrow an
environmental impact
assessment (EIA) was
carried out and as a
result the ‘twin rivers’,
Longford and Duke of
Northumberland’s
rivers, which run across
the site were diverted.
Case Studies
Research one of the following conservation projects , the organisations involved, whether it is in
situ or ex situ and the success of it. Why is it important to conserve these species? Include
references.
• Scimitar-horned oryx
• Great bustard
www.marwell.org.uk
http://www.rspb.org.uk/ourwork/conservation/projects/greatbustard.asp
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African Elephant
Polar Bears
Orangutans
Mountain Gorilla
http://www.panda.org/what_we_do/endangered_species/