Losing the conker fight?

The International Union for Conservation of Nature (IUNC) has been doing the research to update its Red List for endangered species, which gives us a picture of biodiversity health.

The research brought together over 150 experts from across Europe to contribute to the project, which was funded by organisations like the European Council, British Entomological Society and National Parks & Wildlife Service Ireland, as well as individual nations like Luxembourg, Switzerland and Netherlands.

One of the headlines of the 2019 update in the UK, published this month, is that the iconic horse chestnut tree is now one of many species on the vulnerable list, as moths and disease take their toll.

Horse Chestnut (photo: Wikipedia)

The IUCN have assessed 454 native tree species across Europe to gauge them for a risk of extinction, and found that 42% of them face being lost completely (rated as - Vulnerable, Endangered or Critically Endangered). The rate is at 58% for endemic species - that is, species that are only found in a specific area; 15% of endemic species (66) are at the Critically Endangered end of the list.

As well as our beloved conker tree, around three-quarters of the 170 or so members of the family that includes Rowan (Sorbus), are assessed as being threatened, and especially Mountain Ash (Sorbus aucuparia) and Crimean Rowan (Sorbus tauricola).

Going back to the conker (Aesculus hippocastanum); listed as being Vulnerable, it has suffered at the hands (or mouths) of the leaf-miner moth. This is an invasive species found in isolated and mountainous parts of Europe like the Balkans. The moth has added to the existing pressure of logging, forest fires and tourism pressure.

"Trees are essential for life on Earth and European trees in all their diversity are a source of food and shelter for countless animal species such as birds and squirrels, and play a key economic role," says Craig Hilton-Taylor, the head of the IUCN Red List Unit.

What's to blame?
There are a wide range of threats and reasons that are causing the danger to these trees (and other species), which include some, or all, of the following;

• Pest and disease
• Competition from invasive species
• Deforestation - and unsustainable logging practices
• Climate change
• Agricultural practices

Dr Steven Bachman, at the Royal Botanical Gardens in Kew, says, "The results reveal a disturbingly high level of extinction risk that requires urgent and effective conservation action at all levels."

What else is at risk?
The new research has also found that almost half of European shrub species are in trouble, as are a fifth of terrestrial molluscs (snails etc.) and bryophytes (things like mosses and liverworts). Mike Seddon, the Chief Executive for Forestry England, says that the climate crisis is posing a real threat to our woodlands. "Our efforts to have resilient forests include planting a greater variety of trees, including native species only grown in the UK."

Terrestrial molluscs play a key role in soil regeneration, and are seen as a good indicator of soil health. They also provide a vital source of food for birds and mammals. 90% of native European  mollusc species are also endemic, so it is worrying that 22% of the 2,469 species are at risk.

"The impact of human-led activities is resulting in population declines and a heightened risk of extinction of important species across Europe. This report has shown how dire the situation is for many overlooked, undervalued species that form the backbone of Europe's ecosystems and contribute to a healthy planet. We need to mitigate human impact on our ecosystems and prioritise the protection of these species."

Luc Bas - Director of IUCN European Regional Office

Research:
https://www.bbc.co.uk/news/science-environment-49838650 
https://www.iucn.org/news/species/201909/over-half-europes-endemic-trees-face-extinction