Nature can recover 

Scientists at ZSL have used long-term space satellite data to monitor and evaluate the impacts of more than 20 years of nature restoration efforts at the Knepp Estate in the UK. The results are remarkable.

A key feature of the work at ZSL is the employment of Nature-based Solutions – an approach which both adapt to and mitigates the impacts of climate change while providing benefits for both people and biodiversity.

These solutions, which include protecting ecosystems such as tropical forests, seagrasses and mangroves; restoring sea beds and peatlands; the rewilding of degraded landscapes; and urban greening, are high-impact, and provide multiple benefits to people and wildlife. ZSL’s aim is to ensure that biodiversity recovery is at the heart of nature-based solutions.

In April 2022, ZSL conservation scientists led on ground-breaking research using satellites to understand the impacts of rewilding efforts over two decades at a famous UK site. The long-standing rewilding project at the Knepp Estate in England has seen key species and native vegetation returned, and has been monitored for the first time from space, showing remarkable ecosystem recovery.

Scientists at ZSL have used long-term satellite data to monitor and evaluate the impacts of more than 20 years of nature restoration efforts. The research gathered satellite data and imagery such as those available from Google Earth to track changes in trees and shrubs from 2001 to 2020 across the 1,400-hectare site. After scouring years of earth observations across seasons, the team pieced together a picture of definitive nature recovery at the site, with results showing that rewilding efforts have led to a 40% increase in areas with trees, and six times more shrubs than before the project started.

The Knepp Estate had been used for several decades for intensive agriculture, but after this was deemed unprofitable, the owners turned it into a conservation site. Since this time, the estate has become home to a diversity of returning wild species, including rare turtle doves, nightingales, peregrine falcons and purple emperor butterflies.

Knepp estate

Rewilding – the process of rebuilding a functioning and self-sustaining ecosystem by restoring natural processes and food webs – is increasingly seen as an important tool to help repair damage to natural ecosystems, which are the foundations of all life on earth.

Satellite data showed that nature has bounced back particularly well in the south side of the Estate where fields were left for long periods before the introduction of herbivore species such as Exmoor ponies and fallow deer. This space exhibited the most significant change in land cover between 2001 and 2020, with the area dramatically switching from brown ‘ploughed’ fields and grassland to shrubs, woody vegetation and trees.

Conservationists who led the study say that these changes would have boosted important ecosystem functions including food sources, habitats, water and soil retention. Lead author and ZSL researcher Henrike Schulte to Bühne said: “This study is the first of its kind to assess the impacts of rewilding on wider ecosystem functions over several decades and at scale, in the UK. The Knepp Estate is becoming a lush and thriving natural habitat, and by using freely available satellite data, we have deepened our understanding of the impacts made by rewilding efforts.”

Measuring the impacts of long-term rewilding projects has thus far been a challenge. This study is the first in the UK to use satellite images to assess the long-term impacts of rewilding as a strategy for a nature positive future.

Knepp estate

Schulte to Bühne added: “Earth observation tools have been vital in helping us to understand more about rewilding and how it’s working. We hope that our work has proven how successful it is, and will be used to assess the impact of other rewilding projects in the future.”

The findings also showed a significant increase in green vegetation, which the researchers believe cannot be entirely explained by rewilding efforts. They suggest these changes could also be attributed to the impacts of warming conditions in South England due to climate change. As climate change is causing broad and damaging shifts in nature, this will need to be monitored closely, and satellite imagery could help.

Senior author and climate change and biodiversity expert at ZSL, Dr Nathalie Pettorelli said: “Restoring nature in the context of rapid environmental change is challenging. To inform conservation action, we need a range of reliable tools that help us assess and predict the impacts of our efforts in the context of rapid changes in climatic conditions; as this study has shown, satellite data are, in that respect, extremely useful.”

By James Wren is the ZSL Executive Director of Fundraising and Engagement. ZSL is working to put nature at the heart of  decision making,  prioritise  biodiversity  loss and  ensure global leaders and policy makers recognise  its interconnections with climate change. You can support ZSL’s global science and conservation work by donating at     



Flying into trouble? 

Climate change is happening at a frightful pace, driving ecosystems well beyond their limits and our collective failure to act is  having  disastrous consequences. Our ever-changing climate is lessening nature’s ability to survive, let alone thrive, increasing the risk of extinction of habitats and wildlife across the world. But there is hope. We know that when given the chance, nature and habitats can recover and even flourish.  

A recent ZSL-led study shows how our latest knowledge of climate change threats must be better connected with conservation action if we are to successfully protect at-risk species – in this instance, seabirds.

Seabirds such as kittiwakes and puffins are being put at higher risk from a disconnection between conservation efforts on the ground, and research on climate change threats. However, ZSL’s new study shows that better integration of the two is possible to safeguard biodiversity.

Seabirds represent one of the most threatened groups of birds in the world with almost half of all species in decline. They are threatened by climate change, with extreme weather events such as heatwaves and powerful storms, and changes in food availability in response to changing climatic conditions, putting increasing pressure on the birds.

Climate change threats, highlighted by European seabird conservation groups, are often poorly understood, and there are several threats highlighted by researchers and conservation groups without clear conservation actions in response. In fact, this study showed that almost a third (29%) of possible conservation interventions aimed at reducing the impacts of climate change, are linked to conflicting evidence or a lack of information to make solid conclusions about how effective they are.

Leading conservation experts working on the study, including ZSL, Cambridge University, BirdLife International, RSPB and the IUCN Climate Change Specialist Group, say that stronger integration is possible and propose a framework to link research and management that could also be applied to other species too.

Lead author and ZSL post-doctoral fellow, Henry Hakkinen said: “There is a real opportunity here to identify missing information and marry existing research on the risks of climate change with effective conservation and wildlife management.”

“Through our work we have identified several climate change threats and conservation actions which are well understood. Seabirds in Europe are heavily researched and receive quite a lot of conservation attention. They are also heavily impacted by climate change, so are a good species group to start with. These gaps urgently need addressing if we want to work out how we can best help seabirds adapt to climate change and survive.”

Sea birds, source ZSL

A series of surveys were sent to more than 180 seabird conservation practitioners across Western Europe. The team identified major knowledge gaps and began tallying up some of the ways in which conservation action could address some of the major threats posed to the species by climate change.

For example, 45% of those surveyed said that disease risk from climate change was a serious threat to seabird populations, but the study unveiled that more needed to be done to monitor the effectiveness of conservation tools available to practitioners to address this. Hand rearing and vaccinations are suggested tools that could help with the issue.

Threats from temperature extremes, storms and habitat alteration due to climate change can have a detrimental effect on seabirds, leading, for example, to reduced food availability and fewer nesting sites. Artificial nests, translocations and protective barriers for nests were proposed as possible solutions. However, while some of these interventions are known to be effective, important knowledge gaps remain.

Our understanding of and the testing of practical responses for protecting biodiversity are lagging behind the rate of climate change. This must change if we are to make substantive improvements and seabirds are an urgent example.

We need action evidence-based approaches and to make decisions based on the best available evidence to safeguard biodiversity. Bridging climate change research and conservation action has never been more important.

Frameworks which link pressures on the environment, their effect on biodiversity and ways society can respond, are often used in global policy making to translate research to action. This paper suggests that the ‘pressure-state-response framework’ could be applied to specific groups of species or ecosystems to identify existing gaps between research and conservation solutions for wildlife most at risk.

Sea birds

ZSL Senior Research Fellow and senior author, Dr Nathalie Pettorelli said: “We need to get better at connecting climate change research and evidence of intervention effectiveness if we are to optimise opportunities to safeguard a future for the species most at risk. Our study provides an easily transferable approach for identifying missing information and areas where connections between research and management need to be tightened to improve conservation outcomes.”

As we prepare for the long-awaited COP15 conference this year, joined up thinking is more important than ever.

ZSL  is working to put nature at the heart of  decision making,  prioritise  biodiversity  loss and  recognise  its interconnections with other environmental issues such as climate change.

You can support ZSL global science and conservation work by donating at


James Wren is the ZSL Executive Director of Fundraising and Engagement. 





A new year, a new start


A new year signifies a time for change for many. 2021 ended with global congresses making firm commitments to the planet – 2022 is now the time to make that change.

In November, as world leaders joined together to make a pledge to a new global agreement, international conservation charity ZSL published an analysis conducted of palm oil producers, which found that 93% have not assessed climate risk, despite the industry contributing significantly to the world’s greenhouse gas emissions.  

Last year we witnessed more natural disasters and observed more species sadly moving closer to the brink of existence, 2022 must be the time that we come together, reduce greenhouse gas emissions and support planet Earth – something ZSL is working tirelessly to do.   

The analysis of 100  producers, processors and traders of palm oil  found that only  seven  companies had conducted and published an assessment of the risks posed to their business by climate change, meaning only 7% of companies are transparent about their operations and finances are likely to be impacted the climate.   

Compiled by ZSL’s SPOTT team – an initiative developed by ZSL to incentivise transparency of reporting and the implementation of best practice – the results show just how slow the palm oil sector has been to act. This comes despite the industry being described as “highly exposed to global and local climate transitions” in a recent report by  Orbitas, due to  the industry’s  high export volume, reliance on land and use of emissions-intensive fertilisers and diesel fuels.  

Oil Palm sappling field, Uganda

Using the scenario  of  global average temperature  rising  1.5°C above pre-industrial levels,  demand will  soon outpace supply  due to population growth and increasing demand for bio energy.  This will push palm oil prices and land value up, increasing pressure on producers to intensify production and putting the environment at even greater risk – unless producers move swiftly towards sustainable low carbon techniques.  

“Unsustainable palm oil production is one of the biggest contributors to habitat loss in the tropics as it involves clearing and burning forests and peatland to make way for palm oil plantations,” says Eleanor Spencer, ZSL’s Sustainable Business Specialist for Asia. “The process of deforestation also contributes to the acceleration of climate change, as does the draining of carbon-rich peat which, once drained, release the stored carbon into the atmosphere. This way of production significantly contributes to global greenhouse gas emissions, and risks accelerating biodiversity loss and contributing to climate-related issues faced by consumers across the world.”   

There is little doubt that the unsustainable expansion of oil palm plantations in Indonesia has played a leading role in the destruction of vast areas of rich tropical forest, which has one of the highest rates of deforestation in the world. This is of enormous conservation concern as these forests are home to threatened species, from the Sumatran tiger to the rhinoceros hornbill, many of which are unique to Indonesia. 

Sumatran Rainforest, by David Johnston ZSL

The urgency of the climate crisis has never been clearer or more widely acknowledged. It’s time for change and we cannot continue if this is at the cost of vital natural ecosystems like Indonesia’s. It is vital that the industry moves forward in a sustainable way.  

To enable change, ZSL developed by an online platform supporting sustainable commodity production and trade, Sustainability Policy Transparency Toolkit (SPOTT). By tracking transparency, SPOTT incentivises the implementation of best practices.  SPOTT assesses commodity producers and traders on the public disclosure of their policies, operations and commitments related to environmental, social and governance (ESG) issues. SPOTT scores companies annually against sector-specific indicators to benchmark their progress over time. Investors,  buyers  and other key influencers can use SPOTT assessments to inform stakeholder engagement, manage risk, and increase industry transparency. 

It’s essential that we empower change and work together towards effective outcomes including reducing global CO2 levels.  Economies worldwide need to come together and make the shift to a sustainable, low-carbon future, we may have to face the fact these dazzling and diverse habitats could be lost. 

Palm Oil and Rubber Plantations Sumatra, by David Johnston ZSL

Together, with radical measures and nature-based solutions we have an opportunity to change the future of our planet. ZSL’s pioneering work around the world shows that nature can return and thrive given the right combination of help. Our vision for the future, a world where wildlife thrives, is underpinned by the Sustainable Development Goals and is led by the power and insight of our world leading science, boots on the ground field conservation and practical experience of caring for endangered animals in our Zoos.  Vitally, our conservation interventions are low-cost and high impact.   

As individuals we have the ability to make change, but we need your help.  At this crucial moment for our planet, I invite each of you to make a transformative change for the future of our shared planet.   We must all put nature at the heart of our decision making.   

Visit to learn more about how you can support us as we create a world where wildlife thrives.    




James Wren is the ZSL Executive Director of Fundraising and Engagement. 


Top photo: Conservation riparian and oil palm in Sumatra, by Calley Beamish, all photos by ZSL



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