Interview of Piero Genovesi ― Resistance Radio

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Hi, I’m Derrick Jensen and this is Resistance Radio on the Progressive Radio Network. My guest today is Piero Genovesi. Piero Genovesi gained a Masters degree in 1989 and a PhD in 1993 in Animal Ecology at the University of Rome, carrying on research on carnivore ecology. Since 1996 he has worked with the INFS (Italian Wildlife Institute – the Italian government research institute for conservation), focusing on carnivore conservation and alien species. He has coordinated several research projects (eradication and management of invasive alien species, patterns of invasions of mammals, economics of biological invasions, etc.) and worked closely with the Italian Ministry of Environment and with several international institutions (such as the Council of Europe, the European Commission, and the European Environmental Agency) to develop guidelines and policies on the management of alien species (he is a co-author of the European Strategy on Invasive Alien Species). In 2000 he was nominated Chair of the European section of IUCN SSC ISSG, and in 2005 appointed Deputy Chair of ISSG. In this capacity he has coordinated many activities on invasive species, providing technical support to States and institutions in the field of invasive alien species management and for the development of policies on the issue. At present Piero is a senior conservation officer with the ISPRA (Institute for Environmental Research and Protection, created by the Italian Government after the suppression of INFS), where he coordinates the activities on alien species management.

So first, thank you for your work, and second, thank you for being on the program.

PG: Thank you so much.

DJ: So can we start by talking about what are invasive species and how big of a problem is this?

PG: When we talk of alien invasive species, we talk of species introduced by man. So this is something that we cause. And we talk of any kind of organism that we introduce outside their natural range. So over the history of man we have moved around the globe, and in many cases we have taken species with us, introducing them into the natural environment outside the natural range where these species have evolved. And when we talk of invasive species, we talk of these introduced species that cause harm to the environment. So we are talking of any kind of organism, from plants to animals, that are introduced artificially outside their range, and that are harmful to the environment.

DJ: It seems to me that these invasive species are probably one of the worst problems facing wild species and wild places, maybe after direct habitat destruction. Because I think about the chestnut blight, I think about chytrid. And those have caused, and are causing, untold harm.

PG: Indeed this is a huge problem for biodiversity globally. We started to realize how severe the impact caused by invasive species is only recently, a few decades ago. In the IUCN community we work a lot with red list data, data related to species at risk of extinction. And from the information we compile from all over the world, we realize that invasive species are the first cause of extinction globally. So in terms of species that disappear, all the data that we have show in the last say 400 years, species introduced by man have caused the larger amount of known extinctions.

Just to give you an idea, about 40% of all known extinctions have been also caused by invasive alien species. And from 15 to 20% have been driven only by invasive alien species. So this is by far the first driver of species extinctions globally.

But of course biodiversity is not only about extinctions. We have many cases such as the ones you mentioned where we have a loss of environments, we have destruction at a lower scale. If we can see the general trends in biodiversity globally, we see that invasive species are probably the second most serious driver of loss of biodiversity after habitat loss and fragmentation.

What is more alarming to us is that this is something that happens in all environments. We have many cases of invasions, as we call them, biological invasions in the sea, in fresh water, in the mainland. And also we see that the trend of invasions is growing at an alarming rate. So, in all environments, in all taxonomic groups, the data we have show that there is a steep increase in the number of new invasions.

DJ: I’m guessing that there is also a correlation, or some sort of relationship between invasive species sort of piggybacking on other harm. Such as that if you have habitat that is fragmented – that if you have a healthy biome it might be a bit more difficult for an invasive species to get a foothold than if the biome is healthy.

Oh, I want to mention one example of this. And I don’t know that this theory is actually shown to be true. But it’s a theory I heard several years ago that made some sense to me, which is that one of the reasons that the chestnut blight was able to successfully kill off the chestnuts was that the passenger pigeons had been eradicated, and passenger pigeons were in these immense flocks that would poop so much they would make the soil very acidic. So the less acidic soil ended up causing the chestnuts to be a bit less healthy than they would have been otherwise and less able to fight off the blight. And whether or not that’s true – the short question I should have just asked is “Is there a relationship between also these invasives and the other problems that the wildlife faces?”

PG: There is a strong correlation between invasive species and other drivers of change. For example, what we have seen is that climate change and the warming globe can facilitate invasions, especially in some areas of the world. Of course, if you think of the Arctic Sea, to give an example, where new routes of navigation have been opened. That of course poses a huge risk to that environment because many more species could arrive there and have an impact.

And of course very often invasive species enter disturbed environments. One element that is important to stress is that the strongest correlation between the number of invasive species and the level of invasions is with the economy. This is a trait that is strongly linked with the globalization of economies. So of course for example we find more invasive species in countries that have higher levels of trade or of tourists. And we see more invasive species in urban areas compared to wild areas because urban areas, or ports, or airports can be entry points for invasive species.

At the same time I think what you said is partly true for some environments, especially for example in forests. An untouched natural environment is less at risk of being invaded in some cases. But we also have to say that in many cases even the most undisturbed areas are vulnerable to invasions. One example is that old information we have showed that protected areas are particularly impacted by invasive species, even regions of the world like New Zealand or the Pacific where the impact by humans has been less severe than for example in Europe or North America. And if we look at some environments, like islands or fresh water, these environments are particularly vulnerable to invasive species, so even if you have a very natural fresh water spring in the mountains, but if you release some predator fish in that environment you are going to destroy it in a very short time. So I don’t think we can only rely on protecting our environment. Invasive species can be very destructive even in areas that are still only moderately impacted by humans and we need to protect these environments particularly, with a particular care of course.

DJ: I would like to come back to the trade question in a little while, but I have a couple more questions first. One of them is: Could you give a couple-three examples of historical invasions for people who may not know? Like, I mentioned chestnut blight. Can you talk about some typically devastating, or atypical, either way; invasions that have happened prior to the present. Like 100 years ago, 50 years ago, 70 years ago, 300 years ago. It doesn’t matter.

PG: Yeah. I’ll try to give you a few examples that show how species can be moved sometimes intentionally and sometimes accidentally. If you think, for example, of the Canadian beaver, that is very familiar for many North Americans, and it’s a very important species for many environments. It’s an ecological engineer, it’s a very important component of the forest environments of the northern part of North America. The Canadian beaver has been introduced intentionally in Tierra del Fuego at the very top of Argentina, at the opposite of the continent just after the second world war, to try to start, for industry in that area. The effects have been just devastating. The beaver has been introduced in a forest that has evolved without this species, so all the trees are vulnerable to the effect of the Canadian beaver and huge areas have been totally devastated by its impact. And the soil in that region is not rich enough to allow a regeneration of the forest. So at the moment there is a very large area between Argentina and Chile that is impacted by the Canadian beaver, and there are attempts to try to preserve this region, this very important region from a biodiversity point of view, from the impact of this introduction.

Another example is the arrival of the zebra mussel in the Great Lakes region. When it was found in the 80’s it took some time to understand how this mollusk had arrived to this area. And then we realized that probably it was moved in the ballast waters of the vessels that arrived from Europe. So probably not everybody knows that all the ships around the world have tanks filled with water that stabilizes the navigation. In that water they transport thousands of species from one region of the world to the other. So in general, when they try to keep the navigation stable, ships have to fill these tanks with huge amounts of water.

In that case, the zebra mussel arrived in the Great Lakes area and in a very short time they became very abundant, and they have this kind of characteristic of creating encrustations. For example, in the pipes that were used for industries. They blocked navigation, they blocked industry, they created a huge economic cost, and they also displaced the native mollusks in that area.

There are many examples, especially in recent times, in the last 100 years. And that is because we have realized that the trends of invasion have exploded from the beginning of the 19th century. About 100-150 years ago due to the increase in globalization of the economies, as I said, with the increased level of trade, of transport, and of tourism.

DJ: So I have been an activist and writer for 20-25 years, and worked on environmental issues for that long. And the issue of invasives is – even with all the work I’ve done on deforestation and other issues, the issue of invasives is one of the most honestly depressing for me. Because it seems that so often – this is a lesson that we haven’t really learned. I’ll give an example. I live in California, in the United States. And the California Department of Fish and Game still intentionally stocks trout in lakes that shouldn’t have these fish in them. And then they eat the frog eggs and cause the local frogs to go extinct. And also cause the native trout, golden trout, to go extinct or to be extirpated from regions. So they’re intentionally actually harming, like you mentioned about the beavers. These are stories we’ve heard again and again.

I don’t know what my question is. I guess I want to express admiration for you, for working on such an important and heartbreaking issue.

PG: Thank you, Derrick. I think it’s very important that people like you stress that we need to urgently work on this issue. And of course, when I describe the patterns of invasions and the huge impacts, there is a risk of just saying there is nothing we can do. That is not true. We are winning a lot of battles and the situation can improve.

I mentioned that the data we have published on the patterns of invasions globally. We still see an increase in all taxonomic groups and in all environments. But at the same time, we start seeing some reduction in the rates of invasions, especially in groups that are moved intentionally. Increasing awareness of the people can reduce the rate of invasion.

Another encouraging development is that many countries around the world, including the European Union, have been working with the European Parliament to develop legislation that has been adopted a couple of years ago. This now regulates the movement of the most harmful species. There are countries such as New Zealand and Australia, and more recently Norway and Iceland, that have a very stringent border system to try not to let in any invasive species in their territories. There is a higher attention also in the developing world. I often attend a political meeting to try to explain the need to work on this issue, and I see increasing attention in, for example, African countries, because they see the huge impacts of invasive species, not only on their environments but also on their livelihoods.

So I think that we can reduce the problem. We cannot stop it. I think it’s impossible to totally stop the movement of species, but we can prevent the most harmful invasions and we can more effectively than in the past manage the current invasive species that are most harmful at present. We have become much more effective than in the past, for example, in removing invasive species from islands, and that has saved hundreds of species and threatened populations.

When we look at the data on the conservation status of threatened species a few years ago, you realize the removal of invasive species from islands has been the most effective conservation action globally. So that has been the kind of intervention that has helped the highest number of threatened species to recover. And we also see that in some cases prevention has been particularly effective. I mentioned the case of the Great Lakes region. A few months ago, the world community adopted an international convention for the treatment of ballast waters. And now all the countries in the world are working at treating these waters to reduce the risk of invasions. Just to give you an example, in the Great Lakes area ships are now required to exchange the water they use in their tanks far from the coast. And just changing the water they use has reduced the rate of invasions in the Great Lakes area 95-99%. So I think it’s possible to do much more, but the first element is that we need to raise awareness in the public. We need to explain what we are talking about and why it is important to work jointly on this issue. Because after all, as I said at the beginning, this is very much linked to our actions and behaviors. So the movement of invasive species is strongly linked to our behaviors. It is humans who release trout and beavers. It is humans who move goods around the world. And without working together and adopting more responsible behaviors, this is not a battle we can win.

DJ: A question I should have asked you at the beginning, or near the beginning, is how is it that so often invasives, just on sort of a ecological or biological level; how is it that so often that invasives do so much harm? Why does that happen? Like the zebra mussels, how did they take over so much, as opposed to what happens in their native waters?

PG: Okay, first of all, it’s only one fraction of all the species that are moved around the world that are harmful. And there are actually many species that are very – many exotic species are very valuable to our lives, so if you think of the food that we eat or the plants that we have in our gardens, many species that are important to our livelihoods are not of native origin, but are not causing any harm. Think of tomatoes in Europe, or potatoes, or whatever. We have brought from the Americas many species that are essential for our livelihood without creating any particular harm to the environment. So in general, what we say is that of the thousands of species that arrive, for example, via ballast water; only a few of them will establish into the natural environment and only a very few of them will create ecological damage.

How does this happen? There are many mechanisms. I mentioned islands. The easiest way, the easiest example to make is predators. So when we introduced rats or other predators into oceanic islands where native species have evolved without predators, without evolving defensive behaviors – for example, there are many islands in the world where – think of Galapagos. Many birds have lost their ability to fly, because they didn’t have predators. So in those cases, the arrival of introduced predators can destroy one species in a few weeks or months. It’s incredibly rapid.

In some cases, invasive species are particularly successful because in the environment where they arrive they find conditions that are suitable. They may find an environment where they don’t have limiting factors that they have in their natural range. So they may have an area without their predators or without parasites that limit their populations. So there is a combination of factors that explains the success of some invasive species. What we can say is that around the world, there is a limited number of species that are successful everywhere. I think we can identify now the species that are more at risk of becoming invasive elsewhere, and that can help us focus our prevention efforts toward those species.

DJ: Could you give a couple of examples of successful invasives eradications programs?

PG: Yes indeed. The most successful examples of eradication of invasive species are on islands. This is not something we can do everywhere for all organisms. In general eradications can be done only on vertebrates. But the removals of rats from many islands in the world have increased enormously the reproductive rate of birds that were living on those islands, for example. In general we estimate that over 300 species have benefited from the removal of rats and other predators.

In Italy, for example, we are working at the removal of the North American squirrel, that is threatening our native squirrel. We have only one species of squirrel in all Europe, the red squirrel. And the arrival of the American gray squirrel is out-competing our native species, with effects on the entire scale of our forest, because native red squirrel was very important for the regeneration of the natural environment. And wherever we manage to remove the American gray squirrel, we see a coming back of the native species or a consolidation of the native populations with wider effects in terms of environmental recovery.

The examples are very many. Many bird species have been recovered after eradication of introduced predators on islands. And for example, in Antigua, a very rare snake, the Antiguan racer, is coming back from the brink of extinction after an eradication of rats. Or if you think of, for example, Langara Island in Canada; the population of ancient murrelets has doubled after the removal of rats from the island. Sometimes the positive effects are incredibly rapid after rat eradications. We have a very endangered species of shearwater, a marine bird in Europe, and in Italy, when we removed rats from the island of Montecristo, we saw the reproductive success of the shearwater on that island passing from zero when the rats were present, to 80% of nests that successfully fledged new individuals in just two years. So the effects can be surprising and very rapid.

DJ: So I want to come back to the introduced US squirrels in Italy in a moment, but before we do that, when you talk about eradication on an island, how big is one of the largest islands where they’ve been able to successfully get rid of rats? Is it like a square mile or 50 square miles? How big an island is feasible at this point?

PG: I think it’s important to make a parallel with the sanitary efforts. We managed to remove smallpox from Earth. We can do huge eradications depending on the effort we can devote to these interventions. One of the most successful eradications has been the removal of rats from the South Georgia region in Antarctica. This has been a huge project that removed rats from over 60,000 hectares. So a huge region. Working with a team of helicopters and many tons of rat baits, rats have been completely removed from the entire region. So it is possible also to remove species from very large areas, depending on the commitment and the resources that are involved.

Another example is the removal of the ruddy duck from Europe. The ruddy duck was introduced intentionally for ornamental reasons, in the past, and it hybridizes with the native white-headed duck, a very rare endemic European duck species. Removal of the ruddy duck has required several years of work by many countries, including Spain, the U.K., Belgium, the Netherlands. But now it’s more or less completed. There are only a few individuals left in the wild and once the eradication is completed this will secure the future for our endangered white-headed duck.

DJ: What is your experience of the general political will of different countries to actually fund these efforts? Do you find that you have to fight very hard for that or do you find that a lot of countries are very eager to do this?

PG: (laughing) No, it’s very difficult to find enough support, because initially this was considered only an environmental problem and many countries in the world don’t necessarily put environment as their top priority. So for example when I talk to the European Parliament, defending the idea of introducing legislation, I explain that this is an area where protecting environment can also help with protecting our industries and our economies, because we show with solid data that if we manage to reduce the problem, if we manage to prevent the arrival of invasive species threatening our environment, exactly the same species are also responsible for harming our economy. And that was a very effective argument for convincing decision makers to work more on this issue. But in general I think it is still an area that decision makers don’t see as a priority and donors don’t see as a priority.

So about a year ago during the World Conservation Congress that was held in Hawaii, we launched what we call the Honolulu Challenge, a global initiative to try to raise attention and more funds to work on the problem of invasive species. But there is still a lot of work to do to convince countries, decision makers, and more generally the entire society that this is an important area of work for conservation.

DJ: As I mentioned earlier, I’ve been an environmental activist for decades, and what you’re saying is reflected in my experience with a lot of activist groups. I’ve worked with a lot of groups that are working on trying to remove dams. I’ve worked with groups that are trying to stop fracking, that are trying to stop deforestation, etc. etc. But there have been fewer groups who are actively working to stop invasives or to remove local invasives.

I see it some. I see it quite a lot especially with plants. But I don’t see the emphasis – I’m merely validating what you just said. I wish there was more emphasis on it.

PG: I agree with you, and I understand that for NGO’s that rely on their memberships and the support of the society this is an area of work that may be less rewarding. It is definitely much less easy to explain to the public than other threats to conservation including climate change or habitat loss or trafficking and so on. For example, in the work I have done in Italy with the American gray squirrel it has been very difficult to explain to some NGO’s, especially those working in animal welfare, that it was important to deal with this threat to protect our species, because after all, we were talking of removing a nice furry animal from the environment. So it’s not simple to explain it. And also in the case of the ruddy duck eradication in the U.K., the Royal Society for the Protection of Birds had a very strong discussion within their membership to explain why it was important to start that project.

So I think the level of attention in environmentalist work is also due to the fact that the actions that are required; regulating trade, regulating movement of species, in some cases removing species; are less appealing to the public and require some time to explain why this is important and why this is essential for the environment. At the same time, I think the level of awareness is increasing and it’s always important to take the time to explain things. In my work, I’ve been involved, for example, in reintroduction of wildlife. Initially, many years ago we thought that this could be a solution to the loss of biodiversity. Then we realized that reintroducing species was not solving the problems that had brought populations down to the levels where they were, was not a solution. We had to explain that it was much more important to work at the habitat scale. And I think it’s a message that has passed through the society. It took time, but it has arrived to the public. So I think we need to be brave and courageous and explain things even if they’re not very appealing, because after all this can lead to raising an understanding of the environment and the complicated relationships that are behind biodiversity and evolutionary trajectories that we want to preserve. And after all, it brings a growing environmental understanding to the public.

DJ: So we have about seven or eight minutes left and I have a wind-down question in a minute. But before we go there, you’ve talked a bit about rat eradication or ruddy duck eradication. What can be done about some of the microorganisms like chytrid or white-nose fungus for bats? What can be done about something that is so small that you can’t put out rat bait or anything like that? What do we do about chytrid?

PG: First of all, let’s try to think of how we’ve treated diseases that impact humans or livestock all over the world. We know that curing is important, treating the viruses or the bacteria is important, but prevention is far more important. So this is one message that is particularly important to give. With the chytrid fungus that is devastating amphibian populations all over the world, the main message is be careful. Don’t move frogs or other amphibians around the world. For example, scientists are now much more aware that they need to sterilize their equipment, they need to be very careful when they capture animals and move them around, and then the trade in amphibians should be very strictly regulated because we have evidence that the amphibians trade has been one of the causes of expansion of chytrid fungus around the world.

So prevention is definitely the key message. The other point is that we have good examples of treatment and management options that have effectively addressed even microorganisms. If you think of the struggle against mosquitoes and the viruses or diseases that they carry, like malaria: My country, Italy, was strongly affected by malaria after the second world war. And now we have totally eradicated the disease from Italy and from many other countries. So it is possible. It requires investments and commitments but it’s doable in many cases.

DJ: So what do you want people who hear this interview and who care about the land where they live, what do you want them to do both locally and what message do you want them to take away that will change how they perceive the world? And then also what do you want them to do globally? How can they support your work too? All three of those questions.

PG: I think what is very important to reduce, to mitigate impacts caused by biological invasions is, on the one hand, to value your native biodiversity. So you know sometimes people perceive the term “biodiversity” as just a combination of species. So people may think that a zoo is more rich in biodiversity. And of course this is not true. So our native biodiversity, the species that live around our gardens and houses are extremely important because they have coevolved in the same area and they have adapted to the very specific local context. So for example in our gardens or for our animals we should value more the use of native species compared to sometimes more colorful exotic species. And the point is that as it has happened with climate change; where a large part of the society has realized that it is important to support political actions to try to reduce the footprint of people and to reduce the use of, for example, industry that creates carbon dioxide; the same should happen with invasive species. We need to work jointly and ask our governments to be more active on this issue, be prepared to do a little more regulating of what we can buy, in order to encourage the development of more effective policies, as in the case of the ballast water convention that I mentioned before. And that has been a great achievement globally.

Nothing can be achieved unless there is support coming from the bottom toward decision-makers.

DJ: So is there anything else about invasives that you’ve wanted to say that I haven’t given you the opportunity to say?

PG: Well, I think that it is essential to remember that not all exotics are bad. Many of them are useful and nice and good to eat. So we are focusing only on a fraction of the species and I think the message is that it is a very serious threat, but in generally we only work on a tiny number of species and altogether we could identify those species and we could work also at a community level to carry on struggles focused on the priority battles to be fought.

DJ: Well thank you so much for your work and for being on the program. And I would like to thank listeners for listening. My guest today has been Piero Genovesi. This is Derrick Jensen for Resistance Radio on the Progressive Radio Network.

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