More than half Portugal's wildlife has come under threat of extinction since the country joined the European Union 20 years ago - and massive redevelopment made possible by EU cash is at least partly to blame, environmental groups have told the BBC.
The Portuguese Institute of Nature Conservation's list of all the species either in grave danger or on the brink of extinction amounts to nearly half of the country's wildlife.
And environmentalists say that the threat has come from the impact of years of intensive development, funded by grants from the European Union.
"Portugal became a democracy in the mid-1970s and then joined the EU in the mid-1980s - and that's brought a lot of inward investment," Eduardo Goncalves of environmental group WWF told BBC World Service's One Planet programme.
"All of that money has been plunged into roads and dams, and things that haven't been planned very carefully."
Since 1986, when Portugal joined the EU, there has been a marked increase in forest fires, dams, and abandonment of farming.
Portugal's ecological footprint is now higher than major economic powerhouses like Japan and Germany - were everyone to use resources at the same rate as the country, three planets would be required.
Mr Goncalves describes the formerly lush and rural areas of the Algarve in the south of the country as "essentially a green desert," and believes there is a "very direct link" between the buildings and new towns and habitat loss and fragmentation.
The mountains above what is now a massive tourist area were once one of the most biologically rich areas of Portugal, home to the Iberian lynx - the world's most endangered big cat - as well as Iberian and Bonelli's eagles.
"The populations of these species now are literally just a few individuals each," Mr Goncalves says.
"They're not viable in the long term."
Indeed, the group SOS Lynx believes that there are no resident lynx left in Portugal owing to a decline in rabbit populations.
This is has been triggered by the introduction of foreign species - in particular, exotic eucalyptus, which was planted extensively in the 1960s as part of a get-rich-quick scheme.
The plant absorbs groundwater, depriving the area of grasses, which are food for the rabbits on which the lynx feed.
Marcial Felgueiras, director of environmental group A Rocha, says that studies indicate many types of butterflies have simply disappeared - such as swallowtails, red admiral and mallow skipper.
He blames this on farms being abandoned in the countryside as tourism makes so much more money.
"Nobody wants the soil for farming - they want the soil to build on," he says.
And insect losses can have a massive impact on the food chain, leading to declines in other species.
Michael Reeve, who runs an information service for people who want to move to Portugal, says that it has been the money on offer from the EU that had transformed the country.
"With the advent of the European Union, people received grants and loans to improve their infrastructure," he says.
One such project saw the roads between Faro airport and Algarve holiday resorts such as Portimao being built.
A journey that used to take around three hours now takes only 45 minutes, he says.
He says this example reflects a broader point - that when people first came to the Algarve, they were attracted by an image of life that they soon found, in reality, to be very frustrating.
Mr Reeve told the BBC: "They saw the man with the cart, the dogs running around, all the families living together, and thought, 'isn't that something we'd love to be part of?'
"Then as soon as they get over here, they don't actually want to live in that - it's just a nice idea. They realise they're pumping water from a well and the electricity goes off every 30 seconds, and what was romantic soon becomes painful to live in.
"So that's changed, because of demand. The reason we have supermarkets springing up around us is because of the expatriots."
He adds that outside investors "don't seem to have any vested interest in whether they're doing good things for the Portuguese economy and environment".
But, with 11 million visitors a year, tourism is Portugal's main industry - and that remains the priority.
Daniel Queiroz, vice-president of the Algarve Tourist Board, says that the Portuguese people want to see their country becoming more modern.
"We Portuguese are making a huge effort for the country to increase the figures in the Algarve - commerce, restaurants, all kinds of business," he says.
"The Algarve has space for more projects.
"We have a lot of investors. Our projects are of course in areas with animals, but they respect the habitats and keep protecting them."