Cangrejos rojos de las marismas, Procambarus clarkii, mazorcas de maíz y patatas, servidos sobre una mesa. Fuente: freepik

Invasive species are among the leading threats to biodiversity, ecosystems, the economy, and human well-being. Once established, controlling their populations becomes highly complex. In this context, promoting the commercial exploitation of these species is increasingly being presented as a management and control option. However, an international group of scientists led by the Doñana Biological Station (EBD-CSIC) with participation from researchers in Switzerland, the Netherlands, and the Czech Republic, challenges this approach and warns of the risks it may entail to conservation. Their findings are presented in an article published in Proceedings of the National Academy of Sciences

In the letter, the authors caution that so-called “invasivorism”—a term referring to the consumption of invasive species—does not constitute a reliable solution to the problem of biological invasions. In fact, in most cases, the economic interests associated with these approaches tend to perpetuate or even exacerbate the problem.

“Invasivorism is often presented as a win–win strategy, based on the idea that consuming an invasive species generates economic benefits while reducing its impacts”, explains Fran Oficialdegui, lead author of the study. “However, the reality is far more complex and, in many situations, once the problem becomes a business, there is resistance to solving it.”

From environmental problem to market opportunity

In recent years, campaigns promoting the consumption of invasive species have gained increasing visibility, being endorsed by public authorities, companies, and even conservation organisations. Slogans such as “If you can’t beat them, eat them!” have become emblematic of media initiatives encouraging the use of invasive species such as lionfish, red swamp crayfish, coypu, Asian carp, and Atlantic blue crab. In all cases, their commercialisation is presented as a sustainable way to manage an environmental problem. 

“What is often overlooked is that the objectives of commercial exploitation and invasive species management are, in most cases, fundamentally opposed,” says Oficialdegui. Although he acknowledges that some invasivorism initiatives may help raise public awareness about the issue of invasive species, there is little evidence demonstrating their effectiveness. In fact, according to Oficialdegui, “turning an invasive species into a valuable resource may create stronger incentives to maintain or even increase its abundance and spread, rather than to reduce it”.

The creation of markets around invasive species can come into direct conflict with conservation goals. When livelihoods depend on the exploitation of these species, reducing their populations becomes economically undesirable. In some cases, this has already led to unintended consequences, such as restrictions on control measures to allow invasive populations to recover

The article highlights the case of the Kamchatka crab (Paralithodes camtschaticus), a species introduced by the Soviet Union into the Barents Sea in the 1960s, which resulted in a significant invasion. Intensively harvested and commercialised ever since, when the invasive population began to show signs of overexploitation—precisely when its impacts could have been reduced—fishing restrictions were introduced to ensure the sustainability of the commercial activity.

“Similar scenarios to that of the Kamchatka crab are likely to occur in the Mediterranean coasts once the commercial exploitation of the Atlantic blue crab (Callinectes sapidus) is fully established and population declines begin,” warns Oficialdegui.

The need for science-based management

According to the authors, the commercial exploitation of invasive species can be an acceptable option in certain contexts, particularly for invasive species that are already abundant and widely distributed, and for which no viable control or eradication options exist. “But that does not mean that ‘invasivorism’ is a magic solution,” emphasises Oficialdegui. “In reality, it is not even an attempted solution, as it cannot be considered a management strategy in itself.”

The study argues that a management strategy aimed at controlling an invasive species requires ecological knowledge framed within a socio-economic context, allowing for the definition of reduction objectives for distribution and abundance, measurable through appropriate indicators. “None of this is part of campaigns promoting the commercialisation of invasive species, which can do more harm than good for biodiversity conservation,” stresses Dr. Oficialdegui.

The article calls for caution when promoting invasivorism and, above all, for clearly separating such promotion from genuine biodiversity conservation actions. “Addressing biological invasions requires long-term commitment, scientific knowledge, and coordinated policies. Simple solutions may be appealing, but they rarely solve complex environmental problems,” the researchers conclude.