The protagonists of appetizing and exotic desserts in all kinds of recipes, blackberries and guava They grow like pests in the Galapagos Islands that threaten to exterminate the endemic species of the Ecuadorian archipelago.where scientists are stationed drones monitoring and controlling its expansion.
What is the approximate area covered by an invasive plant and how much effort is required to control it? Are there compositions of plant species that support or limit the habitat range of threatened animals?
These are some of the questions they want to answer with data from very high resolution maps showing the distribution and abundance of invasive plant species such as blackberry and guava, as well as invasive plant species such as Cuban cedar and quinine.
Satellite images and drones they want too map key endemic plant speciesaspect Scalesia pedunculata wave myconia robinsoniana Guiding management actions for the restoration of terrestrial ecosystems, also known as the Enchanted Islands.
almost extinct forests
Native to the Galapagos, Scalesia includes: fifteen speciesThree of them are trees that can grow up to fifteen meters, but there are also specimens in arid areas, some of which are small shrubs that emit a delicious perfume.
In the upper reaches of Santa Cruz Island and others in the Galapagos, Scalesia forests could be seen, but only 3% of what they have remained due to agriculture in the past and now due to invasive species, particularly blackberry. German Heinke Jäger, restoration ecologist at the Charles Darwin Foundation (CDF), told Efe.
For this reason together Galapagos National Park Directorate (DPNG) is trying to “save this Scalesia from extinction” in Santa Cruz, and for this they are working on about 300 hectares of forest remnants from more than 10,000 forests in the mountainous regions.
Morea, “the most serious plague”
Jäger, PhD, from the Technical University of Berlin with postdoctoral research on invasive species of the Galapagos at Brown University (USA), claims that the blackberry, introduced in the archipelago around 1968, was the “main threat” and has since become “the greatest threat”. plague more serious here.” The spiny, climbing plant competes for space with Scalesia. “It gives too much shade and doesn’t let its seed grow”.
In addition to being native to the archipelago located about a thousand kilometers from the continental coast of Ecuador, Scalesia is very important because there are many species associated with it. In lichens and mosses growing on its branches, Living insects that feed on birds, such as Darwin’s finches. And since there are insects that only feed on Scalesia, its disappearance could drive certain species of moths to extinction, for example.
Manual and technology control
to check plagueDPNG park rangers cut the blackberry by hand and then applied herbicides in a seemingly never-ending job: “We’ve been controlling the blackberry for eight years on a fourteen-hectare experimental site, and the blackberry continues to regenerate.”
And this, tiny seed Some of the blackberry remains on the ground, but is also spread by animals in their excrement wherever they go, making the task of controlling it enormous.
Therefore, scientists worked on machine learning algorithms To find the perfect recipe for mapping various plant species with aerial photographs taken with drones and satellites.
despite satellite images They have lower resolution than drone photographs, their potential lies in the fact that they cover the entire study area and have eight color channels instead of four, including the infrared range, which makes it easy to characterize plant species with different chlorophyll concentrations.
Combined with the information from the drone, a statistical model In the humid regions of Santa Cruz, Floreana, Isabela and Santiago it is called the “Random Forest”, which identifies each species by color parameters and estimates it to satellite imagery to obtain an approximate distribution of its abundance and indoor area.
well They document changes in plant communities in the GalapagosAn archipelago that, because of its biodiversity, served the scientist Charles Darwin to develop his theory on the evolution of species, and where some alien species are now threatening the extinction of others.