Invasion in the wild – The Day

Some, like the cat’s tail (‘Pennicetum setaceum’), can be seen with the naked eye and in almost any rural area on the Island. So much so that some people think that they were always there, and this is not true because they are invasive exotic species that gradually take over the ecosystem.

The cat tail (Pannicetum sarteacum) is visible almost in any natural space of Tenerife. Even, Many people think that this straw-like bush that grows on the sides of the roads has always been with us. Nothing is further from reality. It is one among many, the best known, of the invasive alien species in the habitat of Canary Islands. On the Island there are more than 1,200 cataloged, although the fight is centered on approximately 200, which already occupy 2,300 hectares when just a few decades ago there were 900. And rising.

Invasive alien species are those that are introduced into other territories and manage to adapt, establish themselves, reproduce and disperse until they colonize the environment, form new populations and cause impacts on biodiversity, health or the economy. Of the 100 most harmful, according to the ranking of the International Union for Conservation of Nature (IUCN), 21 have established themselves on our Islands (11 animals and 10 plants). Of these, 18 have chosen Tenerife, seven in the field of flora. The most recognizable is, without a doubt, the cat’s tail, but there is also the Mexican parasite, the cochineal Dactylopius opuntia, which affects the prickly pears and, therefore, the crops of the traditional picos or prickly pears, which both forms are called It mainly affects the areas near the southern coast of the island.

Everything has a beginning to reach this end. What could be controlled at a given moment has escaped any possibility of stabilization. Years have passed and cat’s tail or Mexican cochineal roam freely. Against them fight a hundred people, volunteers and professionals, or the good intentions of groups and individuals.

work of titans

The Cabildo has removed in 2021 more than 678 tons of invasive exotic flora from the Island. The Minister of the Natural Environment and Security, Elizabeth Garcia, explains that earthworks or the cultivation of foreign ornamental plants in gardens can lead to the uncontrolled spread of these plants. Specifically, there were 678,677 kilos of remains, of which 170,860 have been transferred to the landfill and 507,817 have been incorporated into the land in the form of fertilizer. In other words, only a quarter of the waste reaches the Arico Environmental Complex. The counselor assesses: “The count of actions against invasive exotic flora shows an increase in the number of plants removed last year.” She considers that “it is good news because it means that the work plan works”. García adds that “invasive plants remain a serious threat to protected areas and island biodiversity.” He considers that “unified criteria must be established to manage this waste, a task that is already done with the municipalities.”

To reach this figure, the twenty crews in charge have carried out 1,136 actions around the island, including reviews of areas where it is necessary to review the work to secure the land and prevent species from germinating again. The area worked comprises 2,568 hectares, which implies 359.78 square meters more than in 2020. Among the different invasive species with which work has been carried out, the Plumero (Cortaderia selloana) and the Indian prickly pear (Opuntia dellinii) stand out, which represent almost half (44.6%) of the total kilos removed from among 60 different plant species.

Guarantee.

The Council of Tenerife recommends that the population pay attention only to the guidelines from authorized shops and nurseries, since “they know the species and their invasive capacity.” In addition, he recommends always asking before planting new species and be wary of the showy flowers that grow on roadsides and lots, as well as those offered by friends and family. “Do not take home any plant” biologists make clear. Among the recommendations for not distributing potentially dangerous species, the Natural Environment area points out that pruning debris and soil should not be thrown into the environment, even if it is clean or dry because it can carry seeds and their expansion.

Workers.

In 2022, 29 unemployed people related to the management and protection of the Insular Environment have been hired through the NOE (New Employment Opportunities) program. The objective is to favor labor hiring, in the internship modality, in order to favor labor insertion, while projects of general interest are carried out by the beneficiary public entities. In this case, the improvement of the knowledge of the conservation of insular biodiversity, the management of protected natural spaces and the Natura 2000 Network. In this way it is possible to develop adaptation and mitigation strategies in the face of the consequences derived from climate change.

Co-financed.

This action is co-financed by the European Social Fund through the Canary Islands Operational Program 2014-2020 with a rate of 85%. The total cost of the project amounts to 781,285 euros, of which 533,428 are requested from the SCE. According to the Biodiversity Data Bank of the Government of the Canary Islands, almost 10,000 wild species live on the Island of Tenerife, of which 887 are exclusive endemisms that cannot be found anywhere else in the world.

Impact.

In Tenerife, the particular ecological conditions under which the insular organisms have evolved causes the negative impact of biological invasions is even greater than on the continents where there are factors such as the lack of adaptation to predators, low genetic diversity or greater vulnerability to exotic pathogens. The island’s Biodiversity Strategy 2020-2030 specifies that the threats of invasive alien species (flowers, animals or algae) on ecosystems and endemic species require a specific plan that incorporates early warning measures to counteract their effects. Among them, the negative impact they generate on insular biodiversity.

controls.

The strategy of the document establishes specific controls that must be regulated more intensively and generated in areas such as island borders, the importation of species, zoological centers and animal stores, botanical gardens and nurseries. On some occasions, invasive species can be exploited to contribute to their eradication and effective management. This is stated in article 7 of Royal Decree 630/2013, of August 2, which regulates the Spanish Catalog of invasive alien species. It establishes that the inclusion in the catalog entails the prohibition of their possession, transport, traffic and trade of live specimens, their remains or propagules (germs), which could survive or reproduce, including foreign trade. This prohibition may be rendered null and void, subject to administrative authorization, “when necessary for research, health or safety reasons”. From the possession of small amounts of material when it is required for the use or specific use of the cat’s tail in the tests of the project of the University of La Laguna to obtain cellulose. The exceptions to a process as dangerous as it is complicated to eradicate. An invasion in nature.