Escalating would save Amazonian palm trees from extinction
“Pecoña”, “estrobos” and “ramp” are the escalating methods which would provide a new breath of air to these Amazonian giants, whose existence is currently threatened due to indiscriminate felling to harvest their fruit.Bogotá D. C., 19 de julio de 2016 — Agencia de Noticias UN-
Universidad Nacional de Colombia (UNal) Biologist Carolina Isaza Aranguren lived for 2 years with Amazonian communities of Leticia and San Martín de Amacayacu in Colombia and Iquitos in Peru. There she analyzed the cropping methods and the threat of felling these species of palm trees: [Euterpe precatoria (açaí), Mauritia flexuosa (moriche) and Oenocarpus bataua (patawa)].
In Amacayacu, near Leticia, she interviewed 12 harvesters of the Ticuna Indians and inquired about the productive cycle, distribution areas, resource abundance perception, cultural expression linked to its use and marketing aspects. Furthermore she observed the community during these tasks and registered how the process is performed.
With this information she determined that chosen adult palm trees are chopped down with hatchets or machetes and according to the Indians this is a safe, fast and easy manner.
She also observed that harvesting takes around 60 minutes, including felling, harvesting and packing the fruit. This task is performed by approximately 3 and 5 people of the same family, especially women.
At Amacayacu they harvest between 1,672 and 2,500 açaí palm trees a year with a total amount of fruits between 19.4 and 29 tons, while they cut down between 35 and 70 female palms trees for 2.5 to 5 tons of fruit.
Furthermore fruit demand of the studied species in the local Leticia market is strongly increasing. To meet the demand they harvest between 201 and 435 tons/yr. of moriche, which means felling between 464 to 1,015 palm trees. Additionally the demand for açaí fruit is between 12.4 and 24.8 tons/yr.
“Palm trees are dioecious (there are distinct male and female individuals). Masculine individuals produce pollen which is usually transported by insects, in the air or other pollinating species to the female palm trees which produce the seed,” she said.
Therefore one of the relevant results is that females trees are most affected. Despite the natural proportion between males and females is one to one, in Amacayacu the relation is three male palm trees for every female. This produces genetic impoverishment and male trees cannot reproduce, finally producing extinction of the species.
Tree climbing, the solution
One alternative to change this consists of using other harvesting methods based on escalating. There are several escalating methods, one is called “pecoña” and consists of tying ropes on wrists and ankles to climb up and down trees. Other two methods are called “estrobos” and “ramp” and consist of using planks as ramps to do the same task.
After performing a series of workshops and receiving escalating equipment donations from different international institutions they started escalating palm trees; and although they felt at risk they understood that only with this method they can have an inexhaustible source of resources.
Although the projections are still short term, they did achieve a change with respect to the harvesting figures versus the impact caused by palm felling. For instance with the same amount of harvest and not chopping trees, production stayed the same.
Furthermore the Palms project team wrote a booklet and distributed it among the harvesters of the area so their harvesting techniques could turn into a sustainable alternative.
Food safety threatened
One of the stages of the project consisted in establishing a comprehensive projection model to assess how harvesting could impact the population of palm trees in the coming years. This is a suitable tool to study the population dynamics and appropriate when the lifecycle of individuals is commanded by two or more variables.
“Analyzing the obtained information they can develop strategies to improve productivity and maximize processes and the steps which have the greatest bearing on population growth and reproduction. Also it is possible to implement management plans so the activity can be sustainable and help environmental authorities take decisions,” she said.
Isaza discovered that the species of the area have an “inverted J” pattern with high seedling production and a strong fall as size increases. This is typical population behavior of species in good regeneration stage and long lifecycles. However adult palm trees harvested with destructive methods are notoriously disappearing in areas where they were abundant.
For instance, if the felling rate of açaí palms continues at a rate of 100 trees per hectare, there will only be 25 individuals in 20 years.
Isaza’s research project directed by Natural Sciences Institute Professors Rodrigo Bernal and Gloria Galeano is part of the project entitled, “Impact of harvesting tropical forest palm trees” with participation of four South American countries (Bolivia, Ecuador, Colombia and Peru) and five European countries (Denmark, Germany, UK, France and Spain).
Read the article in its entirety in Spanish at UN Periódico(Por: Fin/ACP/DMH/APBL