A wetland supports rare bird species, stores floodwater and attracts paying visitors.
Distinguish between an ecological, an economic and an ethical justification for preserving this wetland.
A degraded wetland was restored in 2020. Table 1 shows selected ecological and economic indicators before and after restoration.
Indicators for the restored wetland
| Indicator | 2019 before restoration | 2024 after restoration | Units |
|---|---|---|---|
| Native bird species | 24 | 36 | species |
| Carbon stored in vegetation and soil | 18 000 | 31 000 | tonnes of carbon |
| Annual flood damage to nearby properties | 2.6 | 0.8 | million US dollars |
| Annual visitor spending in local area | 0.4 | 1.3 | million US dollars |
Calculate the percentage increase in the number of native bird species between 2019 and 2024.
Identify one economic benefit of wetland restoration shown in Table 1.
Explain, using Table 1, why both ecological and economic justifications may be used to support preservation of the wetland.
A threatened bird is bred in a zoo. Captive-bred birds are later released into a protected area where nesting sites are managed and the cause of the original decline is reduced.
Identify one ex situ measure and one in situ measure used in this programme.
Outline why this mixed conservation approach may be more effective than captive breeding alone.
A pharmaceutical company seeks access to a plant genetic resource and associated knowledge held by a local community.
Outline how the Nagoya Protocol may apply to this situation.
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Figure 1 shows alternative designs for protecting the same total area of woodland.

Identify the design expected to have the lowest proportion of edge habitat.
Outline one benefit and one possible ecological risk of the wildlife corridor in design D.
State one biological characteristic of a target species that should be considered when deciding the width of the corridor.
A degraded wetland landscape contains fenced former ranches and several locally extinct large-animal species.
Outline two rewilding measures that could regenerate natural processes in this landscape.
State one national-level and one international-level measure that could support the project.
The fictional Marula Delta contains mangrove forest, mudflats and fishing settlements. A proposal would convert part of the delta into commercial shrimp ponds.


Using Figure 1(b), calculate the difference between the total estimated annual monetary benefits of conserving the delta and converting part of it to shrimp ponds.
Distinguish between the ecological and economic justifications for conserving the mangroves, using evidence from the figures.
Explain two reasons why the monetary estimates in Figure 1(b) do not represent the total value of the delta.
Evaluate the proposal to convert 400 ha of the delta to shrimp ponds.
The fictional Nembi forest supports a threatened ground-dwelling mammal. The species avoids farmland and requires shaded forest for dispersal.


Calculate the percentage reduction in mammal detections from interior forest to edge forest.
Explain why design A is likely to contain more suitable habitat for the target species than design B.
Analyse one benefit and one possible limitation of the corridors in design D.
Justify which reserve design should be selected to conserve the target species.
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A conservation programme was established for the island ground parrot, a threatened species. Figure 1 shows changes in its captive and wild populations. Management actions are annotated on the figure.

Calculate the overall change in the wild adult population from 2015 to 2025.
Describe two trends in the captive and wild populations between 2020 and 2025.
Explain why the programme is an example of a mixed conservation approach.
Two alternative designs, A and B, have been proposed for a forest reserve intended to protect an interior-nesting bird. Figure 2 shows the designs and results from existing forest fragments with similar characteristics.

Calculate the boundary-length-to-area ratio for each reserve design. Give the ratios in .
Suggest why Design A supports more breeding pairs than Design B.
Suggest one benefit and two possible limitations of the proposed wildlife corridor in Design A.
Agriculture and livestock fencing were removed from a degraded wet grassland in 2018. Native grazing animals were reintroduced in 2019. Figure 3 shows selected indicators of regeneration.
Selected indicators of wet-grassland regeneration, 2016–2025.
| Year | Native vegetation cover / % | Native species recorded / number | Active-management input / staff hours |
|---|---|---|---|
| 2016 | 24% | 33 | 4100 |
| 2017 | 23% | 32 | 4150 |
| 2018 | 22% | 31 | 4200 |
| 2019 | 25% | 32 | 3900 |
| 2020 | 29% | 34 | 3500 |
| 2021 | 33% | 37 | 3100 |
| 2022 | 37% | 39 | 2700 |
| 2023 | 42% | 41 | 2300 |
| 2024 | 45% | 43 | 2000 |
| 2025 | 48% | 45 | 1800 |
Calculate the percentage increase in native vegetation cover between 2018 and 2025.
Describe the relationship between native species number and active-management input after 2018.
Explain how the trends support the claim that rewilding is making the ecosystem more self-sustaining.
A government proposes a strictly protected reserve on land traditionally used by a rural community. An alternative proposal allows community-managed sustainable harvesting in a buffer zone while retaining a strictly protected core.
Explain how an ecocentric and an anthropocentric perspective may lead to different preferences between the two proposals.
Outline two ways environmental justice could be incorporated into the reserve's establishment.
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A wetland is supported by an international convention, managed by a national conservation agency and assisted by an environmental NGO.
Explain one reason why the national conservation agency may have greater direct influence than the NGO.
Outline one advantage and one limitation of the international convention's involvement.
A rewilding proposal would convert marginal farmland into connected native habitat and reintroduce large herbivores and predators.
Explain one ecological benefit of the proposal.
Explain one land-use limitation of the proposal.
A forest-restoration project reports that it planted its target number of trees within budget.
Outline the three levels at which the success of this project should be assessed.
A protected forest introduces permit-controlled wildlife tourism. Part of the permit revenue is allocated to ranger patrols and nearby community enterprises.
Explain how this ecotourism scheme could create a reinforcing relationship between the community and biodiversity conservation.
Outline two limitations that could prevent the scheme from supporting both local well-being and biodiversity.
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In 2015, cattle ranching ended in the fictional Estrella Wetlands. Fences were removed, channels were reconnected and two locally extinct native herbivores were reintroduced in 2018.

Figure 3(b): Annual indicators of wetland regeneration, 2013–2024.
| Year | Intervention | Native plant richness / species | Connected habitat / % | Breeding waterbird pairs |
|---|---|---|---|---|
| 2013 | — | 21 | 36 | 60 |
| 2014 | — | 22 | 38 | 64 |
| 2015 | Ranching ended | 22 | 39 | 65 |
| 2016 | — | 24 | 43 | 72 |
| 2017 | — | 26 | 47 | 81 |
| 2018 | Herbivores introduced | 28 | 52 | 91 |
| 2019 | — | 30 | 57 | 101 |
| 2020 | — | 32 | 62 | 112 |
| 2021 | — | 34 | 66 | 121 |
| 2022 | — | 36 | 70 | 130 |
| 2023 | — | 38 | 73 | 137 |
| 2024 | — | 39 | 76 | 142 |
Using Figure 3(b), calculate the percentage increase in the number of breeding waterbird pairs between 2014 and 2024.
Identify two rewilding methods used at the Estrella Wetlands.
Explain how reintroducing native herbivores could contribute to the regeneration shown in Figure 3(b).
Suggest two additional measurements that would help determine whether the wetlands are becoming self-sustaining.
Evaluate the evidence that the Estrella project has successfully regenerated natural processes.
The wild population of the fictional Luma tortoise declined because of egg collection, invasive rats and loss of coastal scrub. A recovery programme began in 2016.


Distinguish between one ex situ and one in situ measure shown in Figure 4(a).
Describe the changes in the wild tortoise population and nest success after the programme began.
Explain why captive breeding alone would be unlikely to secure the long-term recovery of the Luma tortoise.
Outline how CITES could support the programme and one limitation of its role.
Discuss whether the mixed conservation approach has been successful.
Three organizations participated in conserving the transboundary fictional Orana Marshes.
Comparison of the three organizations involved in conserving the Orana Marshes.
| Organization | Organization type | Authority and reach | Likely response | Funding | Public and field role |
|---|---|---|---|---|---|
| Wetlands Accord Secretariat | International organization | High diplomatic reach; cross-border coordination; no direct enforcement | Slow | Medium; stable | Limited public media |
| National Marsh Agency | Governmental agency | Applies drainage ban; employs state rangers | Medium | High; election-dependent | Formal public communication |
| MarshLife Alliance | NGO | Cannot pass or enforce laws | Rapid | Medium; donation-dependent | Very active social and news media; strong volunteer network; flexible field teams |

Calculate the percentage decrease in annual illegal-drainage incidents between 2018 and 2024.
Compare the likely speed of response and political influence of the National Marsh Agency and MarshLife Alliance.
Analyse how the organizations may have complemented one another in producing the outcomes shown in the graph.
Evaluate the claim that the type of organization is the main factor determining conservation success in the Orana Marshes.
Three organizations participated in the conservation of the transboundary Luma Marshes. Table 2 compares their characteristics.
Comparison of organizations involved in conserving the Luma Marshes.
| Characteristic | Luma Wetlands Treaty Secretariat | Norland Conservation Agency | MarshLife Network |
|---|---|---|---|
| Organization type | International | Governmental | NGO |
| Median response time to reported habitat threat / months | 18 | 3 | 1 |
| Annual conservation resources / USD million | 24 | 110 | 8 |
| Direct power to enforce national environmental law | None | High | None |
| Media audience | Moderate international | Low national | High international |
| Main constraint | Diplomatic agreement among member states | Changing government budgets and priorities | Dependence on grants and voluntary cooperation |
| Main outcome | Coordinated monitoring standards across 4 countries | Prosecuted 63 illegal drainage cases | Restored 1400 hectares through landowner agreements |
Identify the organization with the shortest median response time.
Calculate how many times greater the annual conservation resources of the Norland Conservation Agency are than those of MarshLife Network.
Analyse why the three organizations may differ in their effectiveness in conserving the Luma Marshes.
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Distinguish between aesthetic, ecological, economic and ethical justifications for preserving biodiversity.
Explain why assigning a monetary value to biodiversity may assist conservation decision-making but cannot represent its total value.
Using named examples, evaluate whether habitat-based conservation is more effective than species-based conservation in preventing biodiversity loss.
Figure 2 represents changes following the restoration of native vegetation in a degraded ecosystem.

Explain how the positive feedback shown in Figure 2 could lead to an alternative biodiversity-rich stable state.
A rewilding organization reports that a reintroduced herbivore increased in abundance during the five years after release. It concludes that the entire ecosystem has recovered.
Outline four additional features of secondary data that should be examined before accepting this conclusion.
Native woodland was restored in the fictional Varda Valley from 2012. In 2016, native fruit-eating birds were reintroduced at Site R, where native tree cover had exceeded a proposed threshold.


State the year in which Site R first exceeded the proposed tree-cover threshold.
Calculate the percentage increase in native tree cover at Site R between 2016 and 2024.
Explain why the process shown in Figure 6(b) is a positive feedback loop.
Analyse the evidence that Site R crossed into an alternative biodiversity-rich stable state.
Explain why biodiversity at Site R would not be expected to increase without limit.
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Gorilla-viewing tourism operates in Mgahinga Gorilla National Park, Uganda. Visitor groups are accompanied by guides and viewing time is limited. Part of the permit revenue is allocated to conservation and nearby communities.

Annual gorilla-viewing permits sold and recorded illegal-entry incidents in Mgahinga Gorilla National Park.
| Year / year | Permits sold / number | Illegal-entry incidents / number |
|---|---|---|
| 2016 | 8 000 | 74 |
| 2017 | 8 900 | 68 |
| 2018 | 10 200 | 59 |
| 2019 | 11 500 | 51 |
| 2020 | 2 700 | 68 |
| 2021 | 6 500 | 54 |
| 2022 | 9 700 | 43 |
| 2023 | 12 400 | 34 |
| 2024 | 14 200 | 29 |
2024 gorilla-viewing tourism revenue allocation and local economic indicators in Mgahinga Gorilla National Park.
| Measure / category | 2024 value / stated unit |
|---|---|
| Total permit revenue | USD 9.2 million |
| Park protection and monitoring | of permit revenue |
| National tourism administration | of permit revenue |
| Community projects | of permit revenue |
| Local guide and porter wages | of permit revenue |
| Other operating costs | of permit revenue |
| Local tourism-related jobs | 310 people |
| Accommodation capacity externally owned | externally owned |
Calculate the amount of 2024 permit revenue allocated to community projects.
Describe the relationship between permits sold and illegal-entry incidents from 2016 to 2024.
Explain how ecotourism could create a reinforcing relationship between local communities and biodiversity conservation.
Analyse two limitations of gorilla-viewing tourism as a conservation strategy.
To what extent does the evidence support ecotourism as an effective and socially equitable conservation strategy at Mgahinga Gorilla National Park?
Native vegetation was restored in part of a degraded valley. Figure 4 shows a proposed feedback mechanism, and Figure 5 shows the observed change in native plant biomass.


Identify two processes in Figure 4 through which animals reinforce native plant growth.
Calculate the difference in native plant biomass between the restored and unrestored sites in 2026.
Explain how the evidence supports the possible emergence of an alternative stable state at the restored site.
Secondary data were used to assess a rewilding project that began in 2017. Figure 6 compares the rewilded site with a similar untreated site.
Annual ecological monitoring data for the rewilded site (R) and untreated comparison site (C).
| Year | Event | Native richness () | Native richness () | Bird pairs () | Bird pairs () | Native cover () / % | Native cover () / % | Survey effort () / h | Survey effort () / h |
|---|---|---|---|---|---|---|---|---|---|
| 2016 | Baseline | 22 | 23 | 8 | 9 | 34 | 36 | 120 | 120 |
| 2017 | Rewilding begins | 23 | 23 | 9 | 9 | 36 | 36 | 135 | 120 |
| 2018 | — | 26 | 24 | 12 | 10 | 41 | 37 | 150 | 120 |
| 2019 | — | 29 | 25 | 16 | 11 | 47 | 38 | 165 | 120 |
| 2020 | Regional drought | 31 | 25 | 14 | 9 | 43 | 34 | 180 | 120 |
| 2021 | — | 32 | 26 | 18 | 10 | 55 | 38 | 195 | 120 |
| 2022 | — | 34 | 26 | 21 | 11 | 62 | 40 | 210 | 120 |
| 2023 | — | 37 | 27 | 23 | 11 | 65 | 41 | 225 | 120 |
| 2024 | — | 39 | 27 | 24 | 11 | 67 | 41 | 240 | 120 |
Calculate the difference in percentage increase in native species richness between the rewilded and comparison sites from 2016 to 2024.
Describe two pieces of evidence suggesting that the rewilding project improved ecological conditions.
Evaluate the strength of the evidence that rewilding caused the observed ecological changes.
Ecotourism was expanded around the fictional Mavuno Forest Reserve. Figure 7 shows questionnaire responses from three stakeholder groups. Figure 8 summarizes 2024 financial information and ecological changes between 2018 and 2024.
Calculate the amount of 2024 ecotourism revenue allocated to reserve conservation.
Compare the questionnaire responses of residents and visitors.
Analyse how the data demonstrate both benefits and limitations of ecotourism as a conservation strategy.
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Explain how the size and shape of a nature reserve can affect its conservation value.
Explain how zoning, wildlife corridors and active habitat management can increase the effectiveness of a protected area.
Using named examples, evaluate the effectiveness of protected areas in conserving biodiversity while meeting the needs of surrounding communities.
Outline four methods that may be used to regenerate natural processes through rewilding.
Explain how reintroducing a keystone species may make a degraded ecosystem more self-sustaining.
Using named examples, evaluate the contribution that rewilding can make to returning humanity towards a safe operating space within the biodiversity planetary boundary.
Distinguish between an international organization, a governmental organization and a non-governmental organization involved in biodiversity conservation, and state one limitation common to all three.
Explain how media use, speed of response, diplomatic constraints, financial resources and political influence may produce differences in the conservation effectiveness of these organizations.
Using named examples of international, governmental and non-governmental organizations, evaluate the claim that political influence is the most important factor determining their success in conserving biodiversity.
The fictional Alto Cervo rewilding project began in 2017 on former farmland. Project reports claim that the project has restored biodiversity and improved local livelihoods.
Ecological indicators at rewilded site R and comparison site C; rewilding began in 2017.
| Year | Species richness / species () | Species richness / species () | Native woody cover / % () | Native woody cover / % () | Eagle pairs / pairs () | Eagle pairs / pairs () |
|---|---|---|---|---|---|---|
| 2014 | 17 | 19 | 25 | 29 | 4 | 5 |
| 2015 | 17 | 19 | 26 | 29 | 4 | 5 |
| 2016 | 18 | 19 | 27 | 29 | 4 | 5 |
| 2017 | 19 | 19 | 31 | 30 | 5 | 5 |
| 2018 | 21 | 20 | 36 | 30 | 6 | 5 |
| 2019 | 23 | 20 | 42 | 31 | 7 | 5 |
| 2020 | 25 | 20 | 48 | 32 | 8 | 5 |
| 2021 | 27 | 20 | 52 | 32 | 9 | 5 |
| 2022 | 28 | 21 | 56 | 33 | 9 | 5 |
| 2023 | 30 | 21 | 59 | 33 | 10 | 5 |
| 2024 | 31 | 21 | 61 | 34 | 11 | 5 |


Calculate the percentage increase in native woody vegetation cover at site R between 2016 and 2024.
Analyse the evidence that rewilding caused ecological recovery at site R.
Compare the perceptions of local residents and visitors shown in Figure 7(c).
Explain two limitations of using the questionnaire results to assess the social success of the project.
Evaluate the overall success of the Alto Cervo project.
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Explain the relationship between positive feedback and the emergence of an alternative biodiversity-rich stable state following habitat restoration.
Explain why evidence of increasing abundance in one reintroduced species is insufficient to demonstrate that a rewilding project has produced an alternative biodiversity-rich stable state.
Using named examples, evaluate whether rewilding should be prioritized over food production on marginal agricultural land.
Outline the three levels at which the success of a conservation or regeneration project should be assessed, and state why assessment at all three levels is necessary.
Explain how ecological monitoring, secondary data and questionnaires could be combined to assess the success of an ecotourism-based conservation project.
Using a named protected area, evaluate ecotourism as a strategy for increasing both biodiversity and the well-being of local communities.