Stink bug invasion leaves homeowners in Guimarães and Braga “in despair”

“Stink bugs are here to stay”, warn scientists

Stink bugs – Latin name: Halyomorpha haly – have become a ‘plague’ in Portugal – driving homeowners in areas of the north “to despair”.

As opposed to their distant cousins ‘bed bugs’ – currently causing a lot of frustrations and discomfort in Paris and other city centres – stink bugs feed on plants.

They began being noticed on national territory in 2018, arriving here reportedly in agricultural machinery imported from Italy. But recently their presence has ‘exploded’, leading to homeowners in the north saying they daren’t open their windows for fear of the bugs infesting their homes. 

According to Rádio Renascença, these bugs will happily feast on up to 300 varieties of plant – meaning agriculture too is at risk.

A kiwi producer is mentioned in current reports which warn, understandably, that a plantation infested by stink bugs will “reduce production and (the fruits’) commercial value”.

So what to do? In Guimarães, Braga and even Lisbon people say they are “stepping on” these bugs “straight away”. But here’s the rub (or rather the stink): in doing so, the bugs eliminate a nasty odour. So the exercise is not a pleasant one, for either party involved.

Compared however to bed bugs – and looking at this situation from a health/wellness point of view, stink bugs are nothing like as ‘worrying’. But for those who enjoy healthy house plants; for gardeners and park keepers, and potentially for agricultural producers, this is an invasion that needs to be tackled. 

And here we arrive at the next difficult point’: investigator João Loureiro, working out of the Centre for Functional Ecology explains “there is no totally effective method of controlling this plague”.

His advice is for people to have a “basin of water with detergent where they (the bugs) can drink water and then get trapped, unable to fly again”.

This presupposes that stink bugs will be thirsty when they arrive in people’s homes, and like the look of ‘basins of water filled with detergent’…

Yes, João Loureira realises the idea has its limitations.

More officially, the DGAV (general directorate for food and veterinary matters) tells Rádio Renascença: “We tried to alert to the occurrence of the first individuals in Portugal, so that the DGAV could act at the time in which it was still possible to control this plague”.

This is true: the DGAV sent out circulars asking people to be on the alert “and photograph the insect” when they spied it – the idea being that then DGAV operatives could ‘act’ to eliminate the bugs before they increased in number.



The entity says that it even went to the extent of constructing ‘a network of traps, the execution of which was assured by various regional services of agriculture and fisheries’.

Sadly, “no examples of the infestation were observed in these traps”.

DGAV adds, perhaps in its own defence, that “the extreme difficulty to control these insects is internationally recognised, as there are no effective insecticides”, and stink bugs’ own life cycles make ‘catching them’ even more problematic… hence this week’s ‘alarming reports’ of “householders in despair”; living behind closed windows; stepping frantically on stink bugs whenever they find them, and prizing them off clean washing (apparently stink bugs like to settle on clean washing and “are very difficult to remove”).

Perhaps, in the final analysis, citizens faced with this “plague” against which authorities appear powerless should consider the difficulties affecting the rest of the world and realise stink bugs are possibly the least of our problems… Alternatively some bright spark could set about inventing ‘an effective insecticide’/ bio-control …

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