The ancient Araucaria araucaria, also known as the Chilean araucaria, has distinctive spiny leaves and intricate branches. Their unusual features, scientists believe, evolved as a defense against towering, long-necked dinosaurs.
Reaching up to 48.8 meters in height and capable of living for a millennium, the evergreen tree is a survivor of the Jurassic era, over 145 million years ago.
The Araucaria araucaria survived the dinosaurs, but today scientific experts consider the tree endangered. Cultivated, the Chilean Araucaria grows in gardens and parks around the world, but in nature the species is only found along the slopes of Patagonian volcanoes in Chile and Argentina.
Fires, deforestation, overgrazing and logging have shrunk the temperate forest where the Chilean araucaria grows. Its large seeds are also a valuable food source for an endemic species of bird, the budgerigar.
These green-toned parakeets fly, in flocks of about 15 birds, from tree to tree looking for good food to fatten up to face the winter. When the birds find their pot of gold, the group can reach more than 100, and they gorge themselves on Chilean araucaria pine nuts.
According to a recent surveydespite the inexhaustible appetite for pine nuts, parakeets may be helping Chilean araucaria trees to survive in Patagonia.
Scientists say the birds act as a buffer against the threat posed by human over-harvesting of pine nuts.
Normally, budgies catch pine nuts and consume them from tens of meters away. Birds often eat the seeds only partially. In fact, the partial removal of the seed coat by the parakeets increases the speed of germination of the pinhões of the araucaria, according to with a 2018 study.
“They [os periquitos] play an important role in the regeneration of araucaria forests, as the partially eaten seeds that they leave on the ground are not selected by the seed collectors and maintain their germination potential”, explain two of the authors of the study, Gabriela Gleiser and Karina Speziale, researchers from the Argentine Biodiversity and Environment Research Institute, at the National University of Comahue.
In addition, they said via email, budgies disperse seeds, meaning the trees regenerate further away from the mother plant.
The authors, Gleiser and Speziale, are also investigating whether parakeets, when jumping from branch to thorny branch, pollinate female cones.
Parakeets are not the only residents who eat these pine nuts. These seeds are also a traditional food source for the indigenous Mapuche people of Chile and Argentina, who deftly climb the monumental trees to collect seeds and grind them into a flour that can be baked into bread. Pine nuts, larger than almonds, are also widely consumed in both countries, especially in Chile.
The Mapuche have the right to collect pine nuts in their ancestral area; however, in addition, local authorities restrict the amount of seed that can be collected for personal and commercial purposes and require a permit, said Gleiser and Speziale.
“Nevertheless, there are many illegal scavengers who collect without respecting collection limits,” added the researchers.
“Human collection of seeds poses a major threat to the reproduction of Chilean araucaria in those populations that are accessible to people, as illegal seed collectors almost deplete the stocks of pine nuts produced by the trees.”
However, pine nuts damaged by parakeets are discarded by collectors and even partially eaten, they can still germinate.
The Mapuche way of life is intertwined with the Chilean Araucaria. However, the link was almost broken during the colonial period until the 1990s, when industrial loggers uprooted the plants from the land, including the araucaria.
Demanding legal protection for the species, the Mapuche clashed with loggers and the Chilean government. The Chilean Araucaria are now protected by law throughout Patagonia.
“Araucarias are like the Mapuche people […] despite being mistreated, beaten, we all remained strong,” said Petrona Pellao, a member of the Mapuche indigenous group.
The Mapuche are now replanting araucaria trees and rediscovering their ancient ancestral practices. The objective is to help the Mapuche cultivate pine nuts in a sustainable way and allow the araucarias to prosper again.
Source: CNN Brasil