Britain’s rare chalk grasslands and dormice are under threat from the mild weather this autumn, and some plants are “confused” and have flowered multiple times, experts have said.
This October, the UK has experienced temperatures more normal for spring or summer, with highs of 19.5C recorded this week, and more warm weather forecast for coming days.
The Met Office forecasts it will in the days ahead be unusually warm in much of mainland Europe, not just the UK, which has been experiencing temperatures above average.
But here, many of our fragile ecosystems have been thrown off by the continuing warmth, with the usual markers of the changing seasons disturbed.
The National Trust has experienced changes in its reserves and gardens throughout the country.
A spokesperson said that rare chalk grasslands in Buckinghamshire and Hertfordshire have been unsettled by the weather: “The longer growing season is having an impact on our chalk grasslands. This is a rare and declining habitat full of delicate and specialised flowers, some of which are extremely rare.
“The grasses that they grow amongst grow more vigorously and are better able to make use of the longer growing season, thus putting the flowers at risk of being overly shaded and outcompeted by the more dominant plants.”
The Wildlife Trusts have also seen some wildlife in their nature reserves threatened by the warmth.
In their Teifi Marshes nature reserve in North Pembrokeshire, Wales, the manager, Nathan Walton, has recorded a significant decline in the dormouse population.
He says: “Dormice numbers found in boxes surveyed have declined over the past decade. It is still uncertain if this is due to climate change with milder winters and less opportunity for a deep hibernation or, more positively, whether the habitat is good enough for them to find other opportunities for nesting without the need for the boxes. Further work with footprint tunnels and thermal cameras is being undertaken to gain a better idea of distribution and numbers.”
One silver lining is that gardeners have experienced an extension of summer, with no cold weather to kill off blooms.
Emma McNamara, the National Trust’s gardens and parks consultant for London and the south-east, said: “I have delphiniums flowering for the third time in my garden in Salisbury, and roses are still in full flow. The warmth is almost creating a second summer, especially after all the rain we’ve had.” She has heard similar anecdotes from some of the gardens in her portfolio.
Another National Trust gardener, Chris Skinner, said: “Here at Sheffield Park and Garden in Sussex we are seeing some of our rhododendrons flowering sporadically during October, some of our trees are still producing new growth and our winter flowering cherries are also flowering the earliest I have seen them in the seven years I have been in the garden. A very strange year indeed.”
In Suffolk, the Trust’s gardeners have seen late flowering heather. About 80% of it didn’t flower because of the summer heatwave and drought, but the mild weather and a little rain has caused it to recover. They have also seen healthy numbers of speckled wood butterflies enjoying the mild weather.
In West Yorkshire, National Trust rangers have noticed a boom in field mushrooms due to the mild, damp weather. Lilac pinkgill (Entoloma porphyrophaeum), an IUCN (International Union for Conservation of Nature) red-listed endangered species, has appeared in the fields for the first time.
This warm weather is thought to be at least partly due to climate breakdown. Index scores in the UK are currently at level 2, meaning temperatures are twice as likely toas normal to be a result of climate change, according to the Climate Central online platform. In southern Europe, across the coasts of Spain, France and Italy, scores are as high as three or four.
