Conservation strategies split into three families: protect the species, protect the habitat, or do both at once. Almost every exam question on this topic is really asking you to sort a real project into one of those three boxes and then judge how well it works.
📚 What you need to know
Conservation strategies are the methods used to protect and preserve biodiversity.
Species-based conservation targets individual species, usually endangered ones, and often uses ex situ methods.
Ex situ = conservation action taken outside the natural habitat: botanic gardens, zoos, seed banks, captive breeding.
Habitat-based conservation protects and restores whole habitats, using in situ methods: national parks, reserves, sanctuaries.
Mixed approaches combine the two, usually by using a flagship or keystone species to justify protecting a whole ecosystem.
CITES controls international trade in endangered species; the CBD is the UN treaty that ties national biodiversity policy together.
You need at least one named example for ex situ and one for in situ. Exams ask for them by name.
Ex situ and in situ: the words that carry the marks
These two Latin phrases are worth learning exactly, because they are the difference between a full-mark definition and a vague one.
Learn these word for wordEx situ = conservation carried out away from the species’ natural habitat. In situ = conservation carried out within the species’ natural habitat.
A quick sorting test: if you could put the conservation work in a building, it is ex situ. If it only works where the species already lives, it is in situ.
Species-based conservation (mostly ex situ)
This approach picks a species, usually one that is endangered, and works directly on it. It is the approach you use when a population is too small or too threatened to survive on its own in the wild.
Botanic gardens
Botanic gardens grow a wide range of plants for science, education and display. They keep plant species alive outside their natural habitats, give endangered plants a safe place to grow, and support research. Kew Gardens in London holds over 30 000 plant species.
Zoos and captive breeding
Captive breeding means breeding animals in controlled conditions such as zoos, aquariums or wildlife sanctuaries. The point is to build the population back up and, ideally, reintroduce animals to the wild. The San Diego Zoo runs breeding programmes for species including the California condor.
Zoos also do two things people forget: they raise public awareness, and they raise money that funds conservation work elsewhere.
Seed banks
Seed banks store seeds from many plant species to preserve genetic diversity. They are a backup copy in case the wild plants are lost. The Svalbard Global Seed Vault in Norway stores seeds sent in from around the world.
CITES
CITES is the Convention on International Trade in Endangered Species of Wild Fauna and Flora. It is an international agreement that makes sure trade in wild animals and plants does not threaten their survival, working through a licensing system that regulates and monitors trade. It has helped protect elephants, rhinos and tigers.
CITES is easy marks if you remember what it actually does: it controls trade. It does not protect habitat, it does not stop domestic hunting, and it only works as well as member states enforce it.
Strengths of ex situ
Works when the wild habitat has already gone or is too dangerous.
Conditions are controlled, so survival rates can be high.
Allows research, education and genetic management.
Seed banks are cheap to run per species stored.
Weaknesses of ex situ
Expensive per animal, and only a few species can be covered.
Small captive populations lose genetic diversity over time.
Animals can lose the behaviours they need in the wild.
Pointless if there is no habitat left to release them into.
Habitat-based conservation (in situ)
This approach protects and restores the habitat so the species living there can look after themselves. It is usually cheaper per species protected, because one protected area shelters thousands of species at once.
National parks
National parks protect large areas of natural habitat, keeping whole ecosystems intact along with the species in them. They also create opportunities for research, tourism and education. Yellowstone National Park in the USA protects a wide range of ecosystems and species, including grizzly bears and wolves.
Reserves and sanctuaries
Wildlife reserves and sanctuaries are areas set aside to protect particular species and their habitats. They often involve local communities directly and allow some sustainable use of resources. The Maasai Mara National Reserve in Kenya protects lions, elephants and wildebeest, among many others.
Why in situ usually wins. Protecting habitat keeps the ecological processes running — predation, pollination, nutrient cycling. Ex situ keeps individuals alive but not the system they belong to.
Mixed approaches: using one species to save many
A mixed approach combines species-based and habitat-based strategies. Usually it works by picking one species that people care about, and using it to justify protecting the whole ecosystem around it.
Flagship species
Flagship species are charismatic, well known and popular with the public — elephants, pandas, tigers. They are chosen because they raise awareness and support, not because they are ecologically special. Protect the flagship species properly and you end up protecting its habitat and everything else living in it.
The mountain gorilla (Gorilla beringei beringei) is a good example. It lives in the Virunga Mountains, spanning Rwanda, Uganda and the Democratic Republic of Congo, and has been threatened by habitat destruction, poaching and conflict. Conservation organisations that focused on gorillas ended up protecting the plants and animals that share that forest.
Flagship species are chosen for their appeal to people. Keystone species are chosen for their effect on the ecosystem. A mixed approach often uses one to protect the other.
Case study
Chengdu Research Base of Giant Panda Breeding, China
A textbook mixed approach: species-based work and habitat-based work running side by side.
Captive breeding: a breeding programme to increase the giant panda population.
Habitat restoration: restoring and expanding the bamboo forest the pandas depend on.
Education and awareness: tours, exhibits and programmes that build public support.
Research and collaboration: work on panda biology with international partners.
Facilities: breeding centres, a veterinary hospital, naturalistic enclosures and research laboratories.
Results: panda numbers up, genetic diversity managed through careful breeding, panda habitat restored, and the wider ecosystem protected alongside the flagship species.
The Convention on Biological Diversity
The CBD is a United Nations treaty aimed at promoting sustainable development and conserving biodiversity. It was signed at the Earth Summit in Rio de Janeiro, Brazil, in 1992.
🧩 What the CBD sets out to do
Conserve biodiversity using a range of different conservation methods.
Ensure the sustainable use of biological resources.
Identify and protect marine areas beyond national jurisdictions.
Through the Nagoya Protocol, make sure the benefits from using genetic resources are shared fairly.
Countries that signed agreed to design and run national biodiversity strategies, and to keep cooperating internationally through further meetings.
The Nagoya Protocol is the bit students skip, and it is the bit that shows understanding. It exists because companies were taking genetic material from biodiverse countries, patenting products from it, and sending none of the profit back.
EXAM QUESTION
Distinguish between ex situ and in situ conservation, using an example of each. [4]
Definition 1
Ex situ conservation takes place outside the species’ natural habitat;
e.g. the Svalbard Global Seed Vault stores seeds from plant species around the world.Definition 2
In situ conservation takes place within the species’ natural habitat;
e.g. Yellowstone National Park protects whole ecosystems along with grizzly bears and wolves.Two definitions + two named examples
EXAM QUESTION
Evaluate the use of zoos as a conservation strategy. [7]
“Evaluate” means both sides, then a judgement. Do not just list what zoos do.
For
Captive breeding can rebuild populations that would not survive in the wild (California condor at San Diego Zoo); zoos educate the public, fund field projects and support research.
Against
Very expensive per animal; small captive populations lose genetic diversity; captive-bred animals may lack survival behaviours; ethical objections to keeping wild animals confined.
JudgementUseful as a last resort and as a support to in situ work, but useless on its own if the habitat is gone – so best used as part of a mixed approach.Both sides + a clear conclusion
💡 Exam tip
Learn the two definitions exactly. “Outside the natural habitat” and “within the natural habitat” are the mark-scheme words.
Carry four named examples: Kew, Svalbard, San Diego Zoo (ex situ); Yellowstone, Maasai Mara (in situ). Chengdu covers mixed.
CITES = trade. CBD = treaty and national strategies. Do not swap them.
For “evaluate” questions, always finish with a judgement sentence that actually takes a position.
Link mixed approaches to flagship or keystone species — that is the syllabus wording.
Remember the date for the CBD: 1992, Rio. Small detail, easy mark.
⚠ Common mix-up
Ex situ is not “in a zoo” only. Seed banks, botanic gardens and aquariums all count.
A national park is not automatically well protected. The label only helps if it is funded and enforced.
Flagship is not keystone. Flagship = popular. Keystone = ecologically critical.
CITES does not ban all trade. It licenses and monitors it, with different rules for different appendices.
Captive breeding is not the same as reintroduction. Breeding is step one; releasing into a suitable habitat is a separate, harder step.
Writing “conservation is good” without naming a strategy scores nothing. The examiner wants the method.
Up next: Designing and Managing Protected Areas — once you have decided to protect a habitat, size, shape and edges decide whether it actually works.
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