‘These shihuahuaco trees are like the wise elders of the forest’
Interview with conservationist Tatiana Espinosa about endangered species now being considered for international protection
If you spend a little time in the Madre de Dios region in the south-east Peruvian Amazon it won’t be long before a truck hauling huge “shihuahuaco” trunks goes roaring by, on its way from forest - or what’s left of it - to sawmill. You wouldn’t know it, but shihuahuaco - a Peruvian timber trade term for certain classes of the Dipteryx genus - is so sought after for furniture, flooring and decking by consumers around the world that, according to scientists, it is being logged to extinction. The state’s response? To ignore the scientists or claim they haven’t done enough research, pay more attention to the timber sector, act non-transparently, take no serious action and, above all, delay, delay, delay.
One of the proposals made to this year’s conference on the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES), which started yesterday in Panama, is that steps should be taken internationally to protect shihuahuaco, also known commercially as “cumaru.” Here, via email, Peruvian conservationist Tatiana Espinosa, who runs an NGO called ARBIO responsible for almost 1000 hectares in one of Madre de Dios’s most remote parts, tells me why shihuahuaco is so unique, why it is so important to biodiversity and climate change mitigation, and why it is now so threatened:
DH: I’d like to start with a personal question. Several different people in Peru all recommended I speak to you about shihuahuaco. How have you come to be so knowledgeable about it?
TE: What I’ve been doing with ARBIO, since 2010, is managing a forest area for ecosystem conservation purposes - research, control and monitoring. Our motivation was to stop the forest being cut down, given that that part of the Las Piedras river basin had been classified as “low commercial value” and designated for “reforestation concessions”, despite being covered in mega-diverse primary forest where there are hardwood trees - the longest-lived - such as shihuahuaco, species that have been commercially popular since about 2000. When I was studying in Costa Rica I came across Dipteryx panamensis - “almendro” - a tree that you’re not allowed to cut down in that country because of its importance for macaw nesting and its slow growth, given that it takes about 500 years to reach a meter in trunk diameter. I was left wondering if shihuahuaco - Dipteryx micrantha, Dipteryx ferrea - would behave the same way. Meanwhile, between 2010-2012 construction finished on the Interoceanic Highway crossing Madre de Dios and we soon saw an increase in deforestation and extractive activities such as gold mining and logging, so we built our operations centre in the forest as soon as possible. In 2018 we began researching shihuahuaco and compiling existing information from other researchers, and it turned out that the growth rate of Dipteryx micrantha is even lower than the Central American “almendro”: to reach 51 cm in commercial diameter it requires more than 300 years in the forest, and to reach one meter in diameter it requires about 700 years! In sum, I think that having direct experience in the forest, living with the threats and understanding what’s going on locally have made me a “go-to-person” on this subject.
DH: What you say about its growth rate is fascinating. Are you aware of a slower-growing tree in the Amazon?
TE: The irony is that, despite the great importance of slow-growing trees, they haven’t been studied much, and their growth rates are still largely unknown. One interesting study was done in 1998 by the [American] scientist Jeffrey Chambers, who calculated the age of 12 Amazonian species, among them Dipteryx odorata, which was 1200 years old with a diameter of 1.2 metres. Age is normally measured by counting the annual growth rings, but in tropical forests they’re almost nonexistent or irregular - hence the difficulty of making these measurements. Species of the Lecythidaceae family such as the Amazonian brazil nut have very slow growth rates too, and live for a long time. In that same study, the age of a Cariniana micrantha, 1.8 metres in diameter, was put at 1300 years.
DH: A letter signed by over 70 scientists that was sent to Peru’s Environment Minister and others back in 2016 described shihuahuaco as “key to the maintenance of biodiversity in Amazonian forests.” This is really crucial to understand. Can you explain that?
TE: The species of the Dipteryx genus - shihuahuaco or cumaru - are all key in maintaining the balance and diversity of the Amazonian ecosystem, due to their slow growth, long life span and the great height that they reach - up to 60 meters. Being very long-lived, they provide nutrients, water and information to younger trees through underground connections. They’re like the wise elders of the forest. For example, research like that by [American] biologist Donald Brightsmith identified Dipteryx micrantha as a key tree species for parrot nesting in southeastern Peru. Because they can live for over 1000 years, cavities in them can remain usable by macaws for decades or even centuries. The fruits of Dipteryx are also an indispensable resource for a variety of species, including green macaws, bats, squirrels and agoutis. Also, because they’re the tallest trees in the forest, they’re extremely important for birds of prey and are a nesting site for the harpy eagle, an endangered species protected by the Peruvian government and on the International Union for the Conservation of Nature’s (IUCN) “Red List.” Without these large trees, the forest would lose its structure, connections and habitat for numerous species. They’re the “pillars” of this complex ecosystem.
DH: So when you cut down a shihuahuaco, it’s not as simple as just “cutting down a tree.” You're impacting a whole “community”, so to speak, or network of different species - a “community” in which the shihuahuaco plays a unique, unusually important role, right?
TE: Exactly. In the forest everything is connected - especially the trees, which are linked by a large underground network made up of roots and fungi connecting one tree to another across kilometers. Studies - such as [Canadian] ecologist Suzanne Simard’s - show that the longest-lived trees act as “hubs” - the energy centres - of this network. All this happens below the ground, while above ground they provide habitat for 1000s of organisms - vines, epiphytes, fungi, lichens, insects, mammals and birds - all the way up to the canopy.
DH: There's another characteristic of shihuahuaco which, especially in these times of climate crises, it’s essential to emphasise: its role in sequestering carbon. How would you describe that?
TE: Yes, hardwood trees are carbon fixers par excellence and they’re very important for regulating the climate. The harder or denser the wood, the more carbon in its structure. Research published in Nature indicates that a Dipteryx micrantha tree 1.58 meters in diameter at breast height and 44 meters tall can store 38 tons of carbon.
DH: Yes, according to that 2016 letter from the scientists, a shihuahuaco can store “almost a third of all the carbon in a hectare of primary forest.” Impressive, huh?
TE: Totally. In one hectare of forest there can be 500 trees and 120 tons of carbon on average.
DH: Let's now talk about the threats. Why are things so bad for shihuahuaco? How has the situation changed in the last 20 years?
TE: Before 2000 it was very difficult to cut hardwoods because the tools weren’t really up to it. The most in-demand was mahogany, a medium density wood that was overexploited, but then about 20 years ago shihuahuaco, this “iron wood”, began to be cut down because chainsaw technology had improved and chains with diamond teeth appeared, making it possible to exploit it. In the last 10 years shihuahuaco has accounted for 54% of Peru's timber exports, with the biggest demand coming from China. All the timber that Peru markets comes from natural forests - there are no commercial plantations with significant production. The “forestry industry” is extracting trees that haven’t been planted, and replenishment depends on each species’ life cycle, growth rate and other variables. Most haven’t been studied, and we’re cutting down species that aren’t going to be replenished within the 20 year cutting cycles.
DH: So you're saying that at the moment there is no way that the extraction of shihuahuaco is sustainable, despite what the companies claim? Despite the fact that some concessions where they’re cutting huge quantities of shihuahuaco have been certified by the Forest Stewardship Council (FSC), which claims to only certify sustainably-managed forests?
TE: That’s right. Our study confirms that shihuahuaco extraction isn’t sustainable. In addition to the slow growth rate, it has a very low “recruitment” rate - there aren’t enough young trees to replace the adults that are being cut. The same was found by a study in the Manu area [in the west of Madre de Dios]. The official CITES data sheets indicate that Dipteryx micrantha and Dipteryx ferrea are critically endangered and vulnerable, but SERFOR [Peru’s National Forests and Wildlife Service] still does not yet list them as threatened. Sustainability in forest management means, among other things, using a resource without causing its long-term decline and damaging ecosystems. In shihuahuaco’s case, that is not being complied with.
DH: And now steps are being taken to protect it. However, I understand that the 2015 and 2016 initiatives, such as the scientists’ letter I referred to earlier, came to nothing. Were you involved in that?
TE: I was aware of it but not involved - I was focused on working directly in the forest at the time. SERFOR’s justification for not taking action or pronouncing on the issue was the existence of “information gaps.” Subsequently, in 2018 I presented the shihuahuaco population research project, which was funded by SERFOR and published in the Revista Forestal del Perú in 2020. There’s now more scientific research showing how serious it is to lose these great trees of the Amazon forest. Time goes by and things get worse. Month after month I see more roads, trucks and tractors transporting timber, and the degraded forest is then turned over to agriculture.
DH: There is now an internationally-coordinated effort to protect shihuahuaco too: the proposal by the EU, Panama and Colombia to protect it through CITES, right? That's due to be discussed at the conference taking place now. What hopes do you have for something concrete to emerge from that event?
TE: What putting the Dipteryx genus on CITES’s Appendix II - which is what is being proposed - does is regulate exports, that’s to say, it introduces export “quotas.” But people will still go into the forest to cut it down, just less so and with more regulation. This is the very least we can do to initiate a shift towards cutting less hardwoods in forests and, instead, restore and plant up deforested areas to meet commercial demand. What’s more, I think the CITES proposal is long overdue. Primary forest fulfils very important ecosystem functions, especially now in the midst of the climate crisis, and that is worth much more than timber. However, there are always interests at stake. Development can’t be sustained by degrading or destroying the forest. We hope that at the national level the government is in favor of incorporating shihuahuaco into CITES and that this is what happens.
DH: My last question. In addition to CITES, what more do you think should be done to protect shihuahuco?
TE: Its inclusion on Peru’s list of nationally threatened flora is pending. The last update was in 2006 - although it should be updated every 4 years, that hasn’t been done. And it’s not only shihuahuaco that’s at risk, but all hardwood tree species, because they’re valued so highly by the market and their natural growth is so slow. For now, the extraction of many of these species from the forest is legal, but probably not sustainable.
DH: Tatiana, thank you very much indeed.