#EnCorto: Three keys to understanding how 204 exotic and invasive species impact protected areas in the Ecuadorian Amazon

Invasive species They appear as one of the main causes of biodiversity loss worldwide. They have the ability to colonize any environment, affecting native species and causing hundreds of extinctions on a local and global scale.

In October 2022, Latin American researchers carried out the first diagnosis and mapping of invasive exotic species in the northeastern Ecuadorian Amazon, a region that is characterized by its great biodiversity and by facing strong pressures for oil exploitation, roads and colonization.

This project determined a total of 204 exotic and invasive species present in the Northeastern Ecuadorian Amazonof which 73% are plants; 26%, animals and 1%, fungi. The objective is that in the future exercises like this can be carried out in other areas of the Amazon or even in other regions of the country that are heavily intervened, such as the coast.

What did the scientists find? We explain it to you in three keys.

1. The methodology

At first, the specialists had to go out practically blindly to search for information on iNaturalist and other citizen science platforms, but they do not really have the species classified as exotic or invasive.

“Making that initial theoretical classification was the great challenge we had in order to execute the project,” he explains. Felipe Espinozacoordinator of the project Diagnosis, Mapping and Development of Technical Plans for the Management of Invasive Exotic Species (IAS) in the northeast of the Ecuadorian Amazon.

Before that, says the expert, there was nothing additional to what was already known empirically about the presence of some invasive species from studies that Colombia had carried out. “Peru has absolutely no information for the region and Brazil has very little, because the border with Ecuador is one of the most remote areas of that country,” says Espinoza.

When they managed to overcome that first challenge, the researchers were able to compare the bases of data from five species registration platforms with information on continental Ecuador which is found in the Global Register of Introduced and Invasive Species (GRIIS), consisting of a validated list of exotic and invasive species throughout the territory.

Subsequently, they carried out three field trips – each lasting approximately 15 days – in areas inside and outside three protected areas present in this Ecuadorian region: the Yasuní National Park, the Cuyabeno Fauna Production Reserve and the Limoncocha Biological Reserve. . The first two areas are among the largest in the country.

“We collected data to obtain data that later allowed us to generate visual information, that is, maps and also have a comparison between what is happening in areas that have land use transformation and areas that are protected,” says Espinoza.

2.The findings

Specialists found 204 invasive species in total. In Yasuní National Park, the largest protected area in mainland Ecuador, researchers recorded 66 of these species, the greatest amount of the three sites where the work was carried out.

In the Limoncocha Biological Reserve, 25 invasive species. There the highest concentration of species per unit area was documented: four per square kilometer. That area is characterized by being isolated from healthy forests and is surrounded by human activities. According to the researchers, Limoncocha constitutes the protected area with the highest risk of impacts.

In the Cuyabeno Fauna Production Reserve, 53 invasive species. The greatest risk factor for this protected area is the periodic flooding that facilitates the dispersal of many species throughout the reserve’s water systems.

However, particularly more serious cases were detected. The scientists highlighted 12 invasive species that, based on their analysis, represent a high or very high potential risk for ecosystems: elephant grassCenchrus purpureus), guinea grass (maximum panic)the brook lily (Hedychium coronarium), the pink banana (Musa velutina), water lettuce (Pistia stratiotes), the domestic pigeon (Columba livia), the black rat (Rattus rattus), the mouthy house gecko (Hemidactylus frenatus), the tropical house gecko (Hemidactylus mabouia), the cattle heron (You’re going to be a cowboy), red tilapia (Oreochromis mossambicus) and the African snail (Lissachatina fulica).

To reach this selection, the scientists asked themselves four key questions: is there climatic similarity between the Ecuadorian Amazon and the native distribution area of ​​the species? Has the species been reported as invasive in countries with climatic similarity to the Ecuadorian Amazon? ? Is it on the list of the 100 worst most harmful invasive alien species in the world? Has it been categorized as invasive in the Colombian or Brazilian Amazon and has it generated impacts? The more affirmative answers, the greater the risk.

3.How did they get to the protected natural areas and what to do with them?

The project also identified the entry routes of invasive species to the northeastern Amazon, mainly to the protected areas of Yasuní, Limoncocha and Cuyabeno. The researchers The existing roads and those under construction to protected areas, population centers, airports, ports and oil wells stand out. Furthermore, flood zones and internal rivers in protected areas are the main movement channel for species from one sector to another.

“We have already identified those 12 species [invasoras de mayor amenaza]. It is necessary to carry out studies, to carry out monitoring, to involve the scientific community, the universities so that they can support in their theses some research work that helps with the monitoring of these invasive species, because until now there is no information about what impacts they are causing. , how they are affecting the ecosystem,” he said Efrain Freireresearcher at Inabio and who participated in the review of the project.

One of the main objectives of this diagnosis and mapping was propose action plans for the three protected areas found in the study area. These plans were based on the 12 prioritized invasive species and four fundamental actions are proposed: the first is to generate an alert, prevention and control list of invasive species in each area.

The second action is to describe the biological characteristics of the 12 invasive species and their possible impacts on protected areas. The third consists of designing a line of prevention and control for those dozen prioritized invasive species and, finally, designing a line of education, communication and research for them.