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What is the IUCN Green Status of Species? An Exciting New Era in Conservation with Prof. Akçakaya

The IUCN Red List—the world's biodiversity barometer—is set for a makeover! An exciting and optimistic Green List (now known as the Green Status of Species) is on the way! But what is it exactly and how will it work? If only we had an IUCN expert at hand to run you through it...

Rhinos brought back from extinction in Uganda at Ziwa Rhino Sanctuary 📸 Josh Robertson


Josh: "Wonderful to have you here Professor Resit Akçakaya, can you please tell us a little bit about yourself?"

Resit: "Thank you for having me, and for this opportunity to talk about this exciting new direction in biodiversity conservation.


I am a professor in the Department of Ecology and Evolution at Stony Brook University, which is on Long Island, New York. I teach ecology, do research in conservation biology, and mentor PhD students. In addition to being a university professor, I'm also a member of IUCN's Species Survival Commission."

Josh: "Just to familiarise our audience, who is the IUCN and what is the IUCN Red List?"

Resit: "IUCN is one of the world's oldest and largest international conservation organizations. It has several 'commissions', the largest of which is the Species Survival Commission (SSC), which is the world's largest network of conservation professionals. Almost all of the 9000+ members of SSC are volunteers, like myself. We primarily work in academia, government, and NGOs, and also contribute to the SSC. My own contribution is in the IUCN Red List programme. I chair a committee that develops guidelines about how species are assessed to be on the IUCN Red List; in other words, how to identify a species as being threatened with extinction.


IUCN Red List keeps track of the status of species in terms of how close they are to extinction.


Those that are close are called threatened species, and are separated into 3 categories: critically endangered, endangered, and vulnerable. But the Red List also includes information on species that are not threatened. Most importantly, it keeps track of how the status of species are changing over time. Some species become more threatened; whereas others improve over time, mainly because of conservation actions. Currently, over 100, 000 species are assessed on the IUCN Red List.

Another role I have in IUCN is as a member of the task force that developed a new system for assessing conservation success, which we had initially called the IUCN Green List."

Josh: "What is the IUCN Green List and how does it differ from the IUCN Red List?"

Resit: "First, let me mention that the green list is now officially called The IUCN Green Status of Species.


It has two basic aims: to measure the recovery of a species, and to measure the value and importance of conservation for the species.


These aims are different from, and complementary to, that of the Red List, which is to sort species according to their extinction risks. Permit me to explain the two aims of the Green Status of Species in a bit more detail.


The first goal is to measure species recovery. This is important, because we want species not just to avoid extinction, but to improve beyond that. We want them to recover to numbers and distribution they had before major human impacts caused them to decline.

Thousands of lesser flamingos at Lake Bogoria 📸 Martin Harvey


The second goal is to measure conservation impact; i.e., to calculate how important conservation is, has been, and will be, for the recovery of the species. We defined 4 metrics for this; collectively they quantify the importance and value of conservation for a species. One of them, for instance, is called Conservation Legacy. It measures how important past conservation has been for the species. Another is called Conservation Dependence, and it measures how important the ongoing conservation measures are for the species."

📸 IUCN

Josh: "How will the Green List, now known as the Green Status, work?"

Resit: "As in the case of the IUCN Red List, teams of experts will assess the Green Status of Species. Each species will be assigned to a category for each of the 4 metrics. For example, a species can be designated as having High Conservation Legacy and Medium Conservation Dependence. These categories will be displayed alongside the species' Red List category, which measures its extinction risk.


Thus, the Green Status is complimentary to the Red List. Together, the Red List and the Green Status will present a complete picture of the conservation status of each species, providing valuable information to policy makers, wildlife managers, and conservation practitioners."

Josh: "What is the Green score and how is it measured?"

Resit: "The Green score measures how close a species is to being fully recovered. The formula for the Green Score takes into account the numbers and the distribution of the species (i.e., how many individuals there were, and where) at a baseline date. It also considers the numbers at which the species would fulfil its functions in the ecosystem."

As apex predators, sharks are key to healthy oceans 📸 Tomas Kotouc

Josh: "The Green Status of Species evaluates how past conservation efforts have contributed to the current status of species – at what date will the baseline of a species status be measured and what are the issues surrounding this?"

Resit: "As I mentioned, we want species to recover to numbers and the distribution they had before major human impacts caused them to decline. So, the baseline is selected to be a date before the major human impacts on the species. For some regions of the world, this date may be 1750 CE, which is the approximate start of the industrial revolution, and considered by many to be the start of the Anthropocene era. For other regions it may be earlier, for instance 1500 CE.


The most important issue surrounding the Green Status concept of baseline is the desire to avoid shifting baselines.


The "shifting baseline" syndrome - in which the status of a species or a natural system is compared only to the recent past - prevents gradual, long-term declines to raise the alarm about environmental destruction. We often compare the current state of nature to what we remember from our childhood. This means that every generation has a new, and a lower, baseline concept of what nature is supposed to look like. This gradual lowering of standards prevents us from having a complete picture of the depletion of species over many generations. The Green Status of Species will prevent shifting baselines by standardising the temporal benchmark for evaluating the conservation status of species."

Josh: "Adding in a species’ functionality into the equation is a fantastic idea, but as you know nature is infinitely complex and interconnected, so to do this properly is extremely ambitious. Do you believe functionality can be effectively and representatively quantified for the Green Status across all species?"

Resit: "Yes, I believe so. Before I explain my answer, let me briefly describe what functionality is, and why it's important to consider. Functionality means that a species occurs at the numbers that allows it to contribute to the ecosystem processes (such as nutrient cycling), to have all its interactions with other species (such as pollination and seed dispersal), and to fulfil its roles in the ecosystem. To go beyond avoiding extinction, one of the requirements for a recovered species is that it's a functional component of the ecosystems in which it occurs. Some species, such as the American Bison, are functionally extinct from many of the ecosystems in which they do occur. We cannot consider such species as 'recovered' even if they are not at any risk of going extinct.

The American bison: a functionally extinct species in many ecosystems 📸 Yathin Krishnappa


Now onto your question. Yes, you are right; nature is complex, and it's difficult to determine what population levels are needed to make a species functional. So, initially, our assessments will be approximate. For instance, they will be based on densities of individuals we see in less impacted areas. As our knowledge grows, we'll be able to make more informed calculations.


Two more points to make on this: First is that The Green Status system has already been tested on about 200 species by about 170 assessors; and the assessors were able to assess functionality of the species they tested. So, the types of approximations I mentioned are useful and are working.


Second, I'd like to mention that there were similar concerns about the Red List in the 1990s, when the new system was first introduced. Some people were sceptical that information would be available to assess the Red List status of more than a few hundred species. Today we have over 100 thousand species assessed. When conservationists understand the value of a certain type of information, they often design their work to obtain that information."

Josh: "At what spatial scale will the Green Status of Species be applied and how will this decision affect the results?"

Resit: "The Green Status is applied to the whole range of the species, but the criteria such as functionality are applied to all parts of the range. In other words, we want the species to be functional not just in one place (say, a national park where it is relatively protected), but throughout its range. To assess this, the species' range is divided into smaller spatial units, and the condition of the species is evaluated in each spatial unit. In many cases, how these subdivisions will be defined is relatively straightforward, because, for instance, the species exist in a few distinct mountain ranges, or in a handful of lakes. Or, sometimes, there are already separate conservation management areas defined for a species. Where none of these apply, the assessors will need to make some decisions. We have developed detailed guidelines for doing this, but I suspect that as we gain more experience, we will refine these guidelines."

Josh: "Why is the Green Status of Species important?"

Resit: "It is important because we need to measure, and communicate to the public, how effective conservation is. That is, we need to tell success stories. We conservationists usually have bad news, and for good reason! There is no denying that we are facing a biodiversity crisis. But if you only give bad news, people get depressed, and even those who care about nature tune out, turn off, and move on to other things.


And, there are many good news stories to give. Conservation works! Even when we think it's not working... For example, many species have remained on the brink of extinction for years, even for decades. In most cases, the fact that they are not recovering does not mean that conservation is not working. Because, in many cases, those species would have gone extinct without the dedicated efforts of conservationists.

Chimps in Kibale National Park are being protected from extinction 📸 Josh Robertson


The Green Status of Species is designed to be an objective measure of that kind of success. This means it will also be an objective measure of failures. This will also be welcome, because differentiating successes from failures will allow us to use conservation resources more efficiently."

Josh: "Where do you see the Green Status of Species in 5 years?"

Resit: "First, I see the Green Status of Species adopted by IUCN as the global standard for measuring species recovery and assessing conservation impact. This process has already started; we completed a 6-week consultation period during which over 17,000 members of IUCN and its commissions were asked to provide feedback on a draft standard, and we revised the draft standard based on the comments we received.


After that, I see it being applied to thousands of species over the next 5 years, and the results being used by governments and conservation agencies to help determine conservation priorities. This would be a great advance, and would prevent some strange and unproductive controversies. Such controversies happen sometimes when the Red List status of a threatened species improves; for instance, it moves from being Endangered to being Vulnerable, which is a lower risk category.


Instead of becoming a cause of celebration, the improvement may become controversial because some conservationists fear that it would lead to fewer resources for conservation of that species. What would prevent these controversies is measuring the Conservation Dependence of species, which is one of the Green Status metrics.


Then, conservation funding decisions could be based on how much the species needs conservation to recover or to remain extant, instead of whether it is on the brink of extinction or not."

After 60 years of decline, the population of the Iberian Lynx (Lynx pardinus) increased from 52 to 156 mature individuals between 2002 and 2012; the species moved from the Critically Endangered to Endangered category 📸 Luke Massey

Josh: "Is there anyway the average person could contribute to helping the efforts of the Green Status of Species?"

Resit: "I can think of at least two ways. One is to encourage their own national or local conservation agencies to adopt Green Status as a way of measuring the success of conservation efforts and to keep track of the recovery of species. The more organizations and governments adopt objective methods of measuring species recovery and assessing the impact of conservation actions, the more effective the Green Status will become.


Second, they can contribute to citizen-science projects, for example by recording their observations of species they are able to identify. This is especially important for people living in or visiting areas of the world other than Europe and North America. Increasingly, our information about the distribution, movement, and behaviour of species is coming from citizen-science databases such as ebird and iNaturalist."

Josh: "What are the biggest challenges with the Green Status of Species?"

Resit: "The biggest challenge is to find the funding necessary to do these assessments, even though it does not actually cost that much to do a full Red List and Green Status assessment. This is mainly because most of the labour and information is freely provided by experts. Actually, these types of conservation assessments are very efficient and effective: they save a lot more money than they use, because they inform conservationists exactly where action is needed and therefore result in more efficient use of conservation funds. It's like spending less than 1% of the funds available for conservation to make sure that the other 99% is used efficiently, and not a penny is wasted. Still, it is harder to convince funding agencies to allocate even small amounts of money for an assessment, rather than for an on-the-ground project."

Josh: "What will be the benefits to conservation if the Green Status of Species goes to plan?"

Resit: "I expect and hope that there will be 3 types of benefits.


The first is a more efficient use of conservation funds, as I have just been talking about.


The second is more ambitious goals for species conservation. The concept of species recovery adopted in the Green Status will benefit species by encouraging conservationists to set their goals higher, aiming for full recovery of functional populations throughout a species' range.


The third is a more optimistic outlook on conservation. As I mentioned before, we need to tell conservation success stories, without downplaying the enormous biodiversity crisis that we are in. The information provided by the IUCN Red List and the IUCN Green Status of Species will give both sides of the picture; raise the alarm about species loss, and also promote conservation optimism by telling people that conservation works, and by celebrating the efforts of thousands of conservation practitioners all over the world."


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