Galicia’s Asian Wasp Problem Predicted To Affect All of Spain: ‘It Is A Serious Risk For Human Health’

THE invasive species of velutina wasp, or Asian yellow-legged hornet, continues to become a growing problem in Spain.

In Galicia, these predatory insects already have a greater presence than the native wasps and hornets themselves, which is causing significant health, economic and environmental problems, according to data from the Xunta de Galicia.

Since 2022, figures show that this insect has multiplied by 56 per cent in 2023. Notifications and calls informing of their presence have already exceeded 43,000 to date, which is well above the 27,500 registered in 2022.

However, the Pontevedra City Council assured that: ‘We could speak of up to 10 nests per square metre’.

Experts believe these insects pose ‘a risk to human health’

As explained by Xesús Feás, a member of the Academy of Sciences of veterinarians and an expert in this species, due to its large presence in Galicia it has already become ‘A serious risk for human health’ due to its stings, which can trigger serious allergic reactions’.

According to the data offered by a study conducted by Feás himself, titled ‘Human deaths from wasp and bee stings in Spain: epidemiology at the state and substate level from 1999 to 2018’, between 1999 and 2018 there were 78 deaths in Spain due to stings from hornets, wasps or bees.

Of these, 28 occurred in Galicia. However, the situation for this community is even more serious if the mortality rate per million inhabitants is observed.

This figure in Spain ranges between 0.02 and 0.15 deaths, while in Galician territory it is 2.2, which clearly shows the problem that this community has.

The predatory insects feed on bees

Health risks are not the only problem, these insects also have a great impact on the economy. They feed on 80 per cent bees. This has a very detrimental impact, because in the end, as Feás detailed: ‘it is a very special livestock farm that is raised to take advantage of its products’.

As a consequence, in places where this hornet is widely established, honey losses in Galicia are already at around 65 per cent in bee colonies.

Due to this situation, the beekeeping sector is also being greatly diminished, with beekeepers being forced to carry out a series of measures to protect their hives.

Mariam Ferreira, a researcher at the University of Santiago de Compostela, who is also a member of the Atlantic Positive project, told 20minutos.es that the methods employed by beekeepers ‘cost almost 8 million euros annually”. That is a figure which represents 10 per cent of the value of honey.

The fruit sector is also suffering

Businesses in the fruit sector are also suffering from the presence of these invaders. The greatest consequences are already seen in wine cultivation since the hornets eat the grapes. ‘If they don’t eat it completely, they leave a wound that can ruin the entire bunch’, explained Feás.

He continued: ‘Social alarm is also a factor to take into account since people are really afraid when they go out into the street after seeing news about it’.

‘Although it is not more aggressive than other species, as it is everywhere and has nests everywhere, the risk of being stung is greater’, the expert pointed out.

This situation is also causing alarm in some areas of tourist activity. Ferreira assured that some professions were being affected: ‘There is fear in certain forestry jobs or in fruit picking’

Ferreira continued: ‘The expansion is very strong’, pointing to forecasts that indicate it will reach ‘the entire national territory’, something which Feás also confirmed.

They have already been ‘found in León and Aragón’

‘Now it is increasing and it is already found in Leon, and Aragon as well’, explained Jorge Galván, the general director of the National Association of Environmental Health Companies (ANECPLA).

He detailed that this was because the species was ‘able to adapt very well’, and that because ‘it has no competition from other predators’, it has great invasion power.

This is due to several factors. The first of them was climate change. This summer’s temperatures have greatly favoured the development of this species and have contributed to other insects also procreating suggested Feás.

‘In winter there were no insects since they began to appear in spring and disappeared at the end of summer’, he pointed out. However, global warming has caused spring to start earlier and autumn to end later.

This means that the reproduction window opens, so now this hornet can be seen for longer, and in addition, ‘it reproduces more times’, explained Galván.

Humans unknowingly help the insects to spread

Human beings also influence this problem. Globalisation, hand in hand with freight transport, also contributed to its proliferation. In fact, the director of ANECPLA compared it to the case of the tiger mosquito, which originally arrived in Spain on tyres from China.

Someone who lives in Asturias and travels to Madrid can carry any type of mosquito, wasp or insect in his car. If one of these lays eggs and breeds, the species in question can settle anywhere. ‘These trips mean that we are unintentionally moving those species from one place to another’, Galván concluded.

To try to deal with this growing problem, experts use some ‘control’ systems, such as the reduction of the piqueras – entrance holes to the hive – or ‘trapping’, explained Ferreira.

The latter ‘is the most widespread method’, although it is not the most selective, since ‘other animals that may be beneficial’ for the ecosystem also fall as a result.

Methods to deal with the wasps are being ‘worked on’

For this reason, the Ministry for the Ecological Transition and Demographic Challenge (MITECO) is already said to be ‘working on other types of traps that allow for much more selective captures’.

Their objective is to reduce the capture of other species, as Ricardo Gómez, Head of Service of the General Subdirectorate of Terrestrial and Marine Biodiversity of MITECO, told 20minutos.es.

Although the Ministry ‘has a control plan in coordination with all the autonomous communities’, according to Gómez, Feás ‘the work that should be done to tackle the problem is not being carried out’.

In his opinion, greater foresight should be made because once this species settles in new areas, ‘combating stings, removing nests or damaging hives becomes very expensive’.

Feás stressed that if the Administration did not take action on the matter with new prevention plans, ‘we will have to learn to live’ with velutina.

He pointed out that although eradicating the insects was ‘very difficult’, it was not impossible either. A greater investment needed to be carried out in ‘genetic manipulation techniques or captive care. You need a management plan, someone to direct the orchestra’, he concluded.