Arnica, pictured, is a species that was at risk of regional extinction in Luxembourg's Oesling
Luxembourg’s biodiversity remains as precarious as ever some 15 years after the publication of the country’s last red list on threatened plants, an expert has said.
The 2005 biodiversity checklist of 1,323 vascular plants found 8% were regionally extinct and 9.2% critically endangered.
“It’s not getting any better. We know a lot of examples of very rare plants that have gone in the last 20 years,” checklist author and head of research unit at the Nature museum Guy Colling recently told Delano.
While 8% may seem high, Colling explains that it is not surprising in a region the size of Luxembourg where plant populations are smaller and spread out. However, he stresses, it remains serious as what happens in Luxembourg is a “precursor of what will happen in larger states.”
“The fact we have so many extinct species already, if they die out in our country, then these species are normally also endangered in neighbouring countries, even if they haven’t disappeared yet,” he explained.
Among the most-recent disappearances is that of the huperzia selago, or northern firmoss, a fern-like plant that was last seen on a single rock in the Mullerthal.
Why are certain plants dying out?
One of the main causes of biodiversity loss is the use of fertilisers for farming and nitrogen from the atmosphere. These methods bombard soil with nutrients, which are good for crops but which destroy the conditions necessary for plants preferring nutrient-poor soils.
Arnica is a typical example of such a plant. Found in the Oesling region of northern Luxembourg, the plant was reduced to six populations in 2000, says Colling. “These kinds of species evolved in an ecosystem where nutrients were rare.”
Guy Colling, pictured, is head of the population biology department at the Natur Musée. Photo: Delano.
How does the loss of plant biodiversity impact insects and birds?
“If you’ve nutrients but no more flowering species, it’s a huge problem for pollinators and birds [who feed on them],” Colling explains. He cites the example of the whinchat or Saxicola rubetra (pictured below), a species which breeds in nutrient-poor meadows, and which is considered extinct in Luxembourg as a breeding bird (it can however be observed in Luxembourg during its migration).
“There are other examples of species which were common 20 years ago and now have gone down,” Colling said, adding: “Most are linked to specific needs, like feeding, if plants go down insects go down and birds go down. It’s a domino effect.”
Is it just intensive chemical use in farming that’s the cause?
Not only. Colling explains that construction and general human activity destroys ecosystems.
What is being done about it?
A solution used in the past has been biodiversity management of grassland areas, but it has its limitations if populations become fragmented or isolated. “If you’ve one bird couple and then something happens, it’s gone,” Colling says.
One response used in relation to the endangered arnica population in Luxembourg has been to raise new, young plants and plant them around the existing mother plants. The plants needed genetically different individuals to make more seeds and it worked. “Now we’re seeing these populations produce young plants,” Colling beams. “That’s a good example, but many others are very endangered.”
Illustration photo shows a whinchat which is considered extinct in Luxembourg as a breeding bird. Photo: Shutterstock
Conservation zones offer some hope, though for Colling existing zones need to be expanded to give plants a real chance of survival. He cites the restorative results being observed in a 2,000-hectare military zone in the Belgian Ardennes, which remain untouched by fertilisers, an ecosystem Colling likens to that of the Oesling 120 years ago.
Incredibly, 120 breeding couples of the now regionally extinct whinchat were seen there. Another success story is the introduction of grazing sheep at open pit mines in the south of Luxembourg. “There was no fertiliser and now we have many orchids and interesting bird species,” he says.
Colling supports organic practices and measures that will better guarantee farmers a living wage. But, more than anything, he wants to see a more integrated approach from ministries to protect biodiversity.
Find out more about Luxembourg’s wildlife and biodiversity at the Natur Musée.