Case Studies

Planning for Papua New Guinea's land and sea


This assessment used Marxan to underpin a systematic conservation planning approach in Papua New Guinea. The goal was to identify sets of areas that meet explicit targets aligned with international and national policies, particularly the Convention on Biological Diversity's Aichi target 11 which aims to protect 17% of terrestrial ecosystems.  

It is worth noting that the assessment focused on biological diversity (e.g., through inclusion of habitats (terrestrial ecosystems and benthic habitats), climate refuges, and rare and range restricted species distributions). While other features such as geological diversity and cultural diversity are aspects of diversity worth conserving, the assessment was constrained by available data. Geological and cultural diversity were captured, where possible, through the expert workshops. However, a more comprehensive assessment of these aspects of diversity would include mapped features across PNG.


A key advancement was the use of Marxan with Connectivity to identify priorities across land and sea taking into account asymmetric landsea connections.

Who were the partners?

Papua New Guinea Conservation and Environment Protection Authority (CEPA), Global Environment Facility, United Nations Development Programme, The University of Queensland and The Nature Conservancy 


PNG2Implementation status

The assessment was completed between 2015 and 2017 but built on substantial planning efforts in the marine realm (2012-2014), and terrestrial realm (2009-2011).  This assessment identifies areas of conservation priority, however it does not dictate the types of activities within these sites. Translation of these mapped areas into conservation action is being undertaken by the Conservation and Environment Protection Authority (CEPA) in collaboration with relevant local partners (e.g. local communities and customary landowners to identify socially acceptable and locally relevant management arrangements). There are a range of conservation strategies that can be used to protect sites identified as conservation priorities within this assessment; these range from legal mechanisms to informal community based arrangements to management planning and activities. The primary objective of this assessment was to provide an updated set of conservation priorities by integrating Terrestrial and Marine Programme of Works on Protected Areas

(PoWPA) in PNG; this set of conservation priorities (see Figure 1) can be used as a roadmap for meeting conservation targets that fulfill PNG’s global conservation commitments (e.g. under the CBD Aichi 11 targets) as well as national targets (such as the Protected Areas

Policy). These areas were vetted by experts through a series of workshops and a subset of these priorities, ‘Areas of Interest’ (AOIs), were identified as areas critical for immediate conservation attention (Figure 2).  Communication products such as individual fact sheets describing the conservation values within these areas were produced to facilitate implementation of conservation programs within these areas.  They are the focus of current efforts in scoping conservation options and partnering with possible funders. 


A link to the report can be found here.

Contact details: 

Vanessa Adams, University of Tasmania. Email: This email address is being protected from spambots. You need JavaScript enabled to view it.

Achieving Balance

Brown Bear morguefile CCThe management plan was able to optimize the protection of environment, resources and cultural heritage. The area is home to endangered species such as the Grizzly Bear (pictured), caribou, and more.

User: Peel Watershed Planning Commission, Yukon Territory, Canada.

Marxan, ArcGIS and Zonation were used extensively in a spatial analysis designed to integrate the management of land, water and resources, including fish, wildlife and their habitats. First to take place was consultation with First Nations, other residents, stakeholder groups and experts to determine issues, interests, and considerations in the Peel Watershed Planning Region. Then conservation values and interests and their indicators were identified, their spatial distribution described and critical issues defined. Finally, the results of spatial analysis were distilled into sets of conservation priorities.

These conservation priorities were then compared and contrasted with other regional conservation initiatives, and their influence on the regional planning process was discussed.

Rezoning the reef & Pacific Island Conservation

GBReef morguefile CCMarxan was redeveloped in order to assist in the rezoning of the Great Barrier Reef, Australia, and was also used to quantify the tradeoffs between conservation and socio-economic factors in the Pacific Islands.

Users: Great Barrier Reef Marine Planning Authority, au, and Wallis, Alofi, and Futuna Islands Environmental Services online publication

An international standard is to conserve 20% of all habitats by 2012. When planning conservation in the small Pacific Islands, the context is more unique due to their small size and heavy reliance on fishing and resources from the coral reefs. Compromises/tradeoffs are expected then, for both conservation and socio-economic /fishing. Marxan was used to be able to, for the first time, quantify these tradeoffs, and work out the optimal balance for conservation in the Pacific.

National Park Extension

Zebra Morguegile CC

Marxan was used to assess the feasibility of expanding the Mt Zebra National Park (MZNP), South Africa.

User: SANParks, Mount Zebra National Park, Africa.

The expansion has created a massive reserve for zebra, elephants, buffalo, big cats and many more animals. It also helped to connect MZNP to other parks, forming a corridor for wildlife and at the same time protecting native grassland habitats.

Read the full story HERE

Planning for a conservation corridor in Maputaland

SF mapBackground

The Maputaland Centre of Endemism is a region in Eswatini (Swaziland), Mozambique and South Africa that is globally recognised for its conservation value. However, this biodiversity is threatened by the spread of agriculture and over-harvesting of natural resources, so the three range states are committed to developing a Transfrontier Conservation Area (TFCA) that will conserve this important region, while also creating jobs through ecotourism. The spatial prioritisation was used to support this process, guiding where new conservation areas should be established based on the distributions of 44 landcover types, 53 species and 14 ecological processes. The results have been used to block unsuitable developments in priority conservation areas, inform the development of a conservation corridor between Maputo Special Reserve in Mozambique and Tembe Elephant Park in South Africa, and to guide funding priorities by the Critical Ecosystem Partnership Fund.


This was a transfrontier conservation planning project that used habitat transformation risk as the cost layer, which acted as a metric of opportunity cost from subsistence agriculture.


Who were the partners?

Eswatini National Trust Commission, Administração Nacional das Áreas de Conservação in Mozambique and Ezemvelo KwaZulu-Natal Wildlife in South Africa


Implementation status

This work began in 2005 and continues to inform the design of conservation corridors, prioritize investments in conservation and guide land-use planning in the region.


Smith, RJ, Easton, J, Nhancale, BA, Armstrong, AJ, Culverwell, J, Dlamini, S, Goodman, PS, Loffler, L, Matthews, WS, Monadjem, A, Mulqueeny, CM, Ngwenya, P, Ntumi, CP, Soto, B and Leader-Williams, N (2008). Designing a transfrontier conservation landscape for the Maputaland centre of endemism using biodiversity, economic and threat data. Biological Conservation, 141, 2127-2138. 

TFCA map

Contact details:

Dr. Bob Smith – This email address is being protected from spambots. You need JavaScript enabled to view it.

Durrell Institute of Conservation and Ecology, University of Kent, Canterbury CT2 7NR, UK