With the arrival of autumn, the brown marmorated stink bug (Halyomorpha halys), an insect of Asian origin that poses a serious threat to Catalan crops, begins its hibernation cycle. This period is crucial for its proliferation, as it seeks refuge in closed spaces such as buildings and homes, increasing its presence in both urban and agricultural areas.

In response to this challenge, the awareness campaign 'El bernat és aquí' (‘The Stink Bug is Here!’), led by the Institute of Agricultural Research and Technology (IRTA), the Barcelona Provincial Council and the Department of Agriculture, Livestock, Fisheries and Food, continues its focus on preventive actions to curb the spread of this pest, with particular attention to crops in the Lower Llobregat Agrarian Park.

A problem of double impact: Urban nuisance and crop damage

First detected in Catalonia in 2016, the brown marmorated stink bug has spread across all the Catalan provinces, establishing itself as a pest with a significant social and economic impact. While in urban areas, it causes inconvenience due to its ability to reproduce and seek refuge in homes and buildings, the most significant damage occurs in agriculture. The pest feeds on a wide variety of crops, from fruit trees to vegetables, causing substantial economic losses.

According to Helena Perxacs, manager of the Baix Llobregat Agricultural Park Consortium, this year, the pest has had an uneven development, with a reduction in populations compared to previous years. This has allowed the pest to remain at low levels without causing damage to crops. However, she warns that "we cannot let our guard down," especially in a region like the Baix Llobregat, with a high population density and agricultural spaces so close to urban areas, where any resurgence could have severe consequences for agriculture.

Citizens as key allies

Citizen involvement is the key to containing the spread of the brown marmorated stink bug. Authorities recommend various preventive actions, such as installing mosquito nets to prevent the insect from entering homes and eliminating any detected specimens using simple methods, such as drowning them in soapy water or using vacuum cleaners to collect them.

Additionally, the campaign ‘El bernat és aquí!’ encourages citizen participation in collaborative science initiatives. People can contribute by sending geolocated photographs of specimens to the Natusfera portal, an essential tool for experts to create accurate maps of the pest's distribution and identify areas where it has not yet been detected or where an alarming expansion is occurring.

Information resources and materials

To reinforce the fight against this pest, the campaign provides citizens with a wide range of outreach materials, including infographics, leaflets, and fact sheets, available through the website www.elbernatesaqui.cat. These resources not only explain how to identify the insect but also offer practical advice on how to act quickly and effectively.

According to Helena Perxacs, "the active collaboration of citizens not only helps mitigate the economic damage in agriculture but also contributes to preventing the brown marmorated stink bug from becoming a serious problem in the future." The campaign, launched in 2022, has been crucial in containing the pest in the Lower Llobregat Agrarian Park.

To preserve local crops and reduce public inconvenience, the Barcelona Provincial Council reaffirms its commitment to continue working in collaboration with IRTA and other institutions to halt the spread of the brown marmorated stink bug and protect agriculture in the region.

For more information on the actions to control the pest in the Lower Llobregat Agrarian Park, please contact Elena Isla, technician at the Lower Llobregat Agrarian Park Consortium.