The raccoon is identified as an aggressive, invasive alien species with a notable impact on both ecosystems and local native species due to its high reproductive capacity. A plan will be implemented to manage their presence in the Tagus River area, extending through Madrid as a central focus of expansion.
The plan will be developed jointly by Castilla-La Mancha, Madrid, and the Ministry for Ecological Transition and Demographic Challenge. It will be launched in January with the Tagus as its axis, since this river serves as a dispersal corridor for the species, as explained to Efe by the head of the State Department’s Natural Areas Service, Antonio Aranda.
The goals include tracing how far the species has spread and attempting to curb their population, given the raccoon’s strong reproductive potential with several offspring per birth and the possibility of two litters within a year.
Moreover, each offspring can reproduce the following year, enabling rapid, exponential growth. The number of individuals can surge if suitable habitats are found, notably along the Tagus and its tributaries, according to Aranda. He noted that riverine environments host the highest concentrations of this invasive species.
Aranda stated that the plan will focus on areas where raccoon specimens have been detected, with Castilla-La Mancha responsible for implementing the plan in Guadalajara and Cuenca provinces, and Madrid overseeing its regional execution. The ministry reported detections from Aranjuez to Talavera de la Reina in Toledo.
trap patrols
To put the plan into action, each of the three administrations will operate at least one trap patrol of experts. They will attempt to capture raccoons with specified traps to remove them from the environment and prevent further spread.
They will also capture specimens of two other invasive alien species present in the Tagus area, namely the raccoon dog and the American mink. The dispersal dynamics may involve young animals moving ahead of established populations, as noted by Aranda.
The presence of raccoons in the wild largely stems from individuals that were kept as pets and later released by their owners, more than two decades ago when they were not yet classified as invasive. In reality, keeping them as pets is discouraged; they are described as unpleasant and aggressive.
Madrid, the focal point of distribution
The Tagus region’s raccoon population centers in Madrid, where large urban areas serve as hubs for the species’ spread. Evidence from 2003 shows stray raccoons around the capital, after which they moved into Castilla-La Mancha.
The raccoon expands through high reproductive output and uses riverbeds as distribution corridors. The head of Castilla-La Mancha’s Natural Areas Service provided details on ongoing colonization efforts toward other regions.
Additionally, the dispersal process begins with young individuals, especially males seeking establishable territories. Thus, the primary objective of the control plan is to determine whether populations are already established or if sightings in various areas reflect dispersing juveniles that have not yet settled.
Compete with native species
During expansion, raccoons compete for territory with other native mesopredator species such as raccoons, badgers, otters, martens, and other similar predators.
This competition can threaten native species. For instance, the Pyrenean desman—a highly vulnerable species—was pushed toward extinction in parts of the Central System due to introduced species, according to Aranda.
The Pyrenean desman has nearly disappeared from the entire Central System, with a small remaining stronghold in a gorge in Gredos where it was located. This example illustrates the potential impact of invasive species on ecosystems, as a group may prey on endangered native species such as turtles, crabs, or certain fish.
In this context, Aranda indicated that efforts will also involve the raccoon dog and the American mink, leveraging coordination with the raccoon program to support broader native species recovery. He stressed that pre-emptive control of invasive species is essential before native species can recover fully.
Evaluating the plan’s implementation will yield important information about the situation and help advance species control, with the ultimate aim of removing raccoons from the wild. Madrid remains the central focus of these efforts.