The guardians of sacred oak forests

The car door slams shut, and for a moment we are blinded by the morning sun. It is 10 a.m. on what seems to be the last warm day of the year and the birds greet us in a joyous choir.

After a 30-minute drive from the Lithuanian capital, Vilnius, we are finally in the Neris Regional Park. FSC certified since 2004, the park offers 10,000 hectares of unique landscapes, historical sites, and a haven for endangered species.

Today's goal is to find ancient trees and learn about the species that depend on them. Immortalized in pagan legends, many of these trees are the last guardians of once vast and sacred oak forests. Today they are home to endangered species. The sleepiest and the fairest of them all, we are told, is the fat dormouse (Glis glis). With its fluffy tail and long whiskers, it will surely steal your heart at first glance. 

One by one, our team members arrive. Tires slide down a forest gravel road, brakes squeak and doors close. We circle around. Saulius and Tadas are park rangers–ecologists and our guides for the day. Adelė, Alvydas, Daiva, and Dalia are ecologists from the Lithuanian Fund for Nature. Today they will show us their work to restore the ancient trees and to protect one of the many species that depend on them – the hermit beetle (Osmoderma eremita). 

If this valley could speak

We head down to the Dūkšta River Valley. Since ancient times, this area has been ideal for human settlements, the oldest of them dating back to the 3rd  century. Protected by tall hills, local Baltic tribes enjoyed fertile meadows and plenty of water and fish. Nowadays, the valley and the neighbouring Dūkšta Oak Forest – the oldest and the biggest of its kind in Lithuania – belong to the Natura 2000 network. 

Down the road, we run into a dome-like hillfort. A signboard reads: ‘Karmazinai hillfort. If you are here on a Sunday at noon, put your ear to the hillside. Can you hear a bell ringing in its depths?’ In Lithuania, such pagan cultural artifacts seamlessly blend into the environment. To this day, ritual fires are lit on the top of Karmazinai hillfort: it is a sacred place where neo-pagans carry out their rites.

Drowning in high grass, we soak up the morning dew. The forest entrance is ‘heavily guarded’: raspberry bushes try to hold us still while nettles aim for our heads. We dodge and twist, sticking to a windy, narrow path. Only the park rangers brave through the thickets – no branch is too much for these two. Finally, we tumble into the forest. Shaded from the sun, the air here is fresh and chilly.   

To our left, a nesting box is booming with life – wasp life, that is. We hurry past it, countless wooden steps down and deeper into the forest. The ground here is covered with thousands of tiny apples. “Do you see this wild apple tree?” Tadas points high above our heads, “its fruits taste like quince.” At first glance, none of these giant trees resemble an apple tree. “Fat dormice love to snack on their seeds, that’s why we often place nesting boxes near apple trees.” 

Mammoth?

Some of us finally spot the apple tree, or we think we do, but the rest of the group is already crossing the River Dūkšta. It rushes over rocks and fallen branches, so loud it even drowns out the birds. Halfway up another hill, we gather around something that resembles a mammoth skull. “Children think this is a funfair slide,” laughs Saulius. “But what you see here is an old oak, fallen six years ago. Oakwood decays very slowly and provides a habitat for many endangered species.” Indeed, 284 invertebrates, 324 lichens, and countless bird and mammal species are associated with oak deadwood. “Forest slopes are where you find enough deadwood. Other parts in forests are more likely to be swept clean for logs,” explains Alvydas. 

In Neris Regional Park, the deadwood is there to stay. At least 5 per cent of the logged volume must be kept as deadwood in any FSC-certified forest. But this part of the park is special: in accordance with FSC regulations, it is set aside and protected as a Representative Sample Area. It is also registered as a habitat of European Importance and belongs to the Natura 2000 network. No logging is allowed here.

The Sacred Daubų Oak

We leave the fallen oak to rest and climb further up the hill. Rays of sun pass through the canopy and play below our feet. And then we see it – an ancient oak tree standing encircled by the forest. At a 2 metres radius from the tree, runs a fence. “This is the Sacred Daubų Oak,” Alvydas introduces us to the first guardian of the ancient oak forest. “It’s over 300 years old, 28 metres  tall, and protected by the state as natural heritage.” We gather below its canopy and wonder how many people it would take to hug this giant.

Many tales are told about the Sacred Daubų Oak and the forest around it. The legend has it that the king of grass snakes appears here every seven years. Locals recall their great grandparents cautioning them to be kind to grass snakes, for they are holy creatures. Where we stand now, according to historical accounts, used to be a vast oak forest. Many pagan shrines are said to have been here. For the Baltic tribes, oaks were sacred: they offered home to ancestor souls and to Perkūnas, the god of thunder. For them, to fell an oak was considered a great crime.

A picky beetle  

Today, trees like the Sacred Daubų Oak are known as microhabitats for endangered species. The hermit beetle is one of them. Included in the International Union for Conservation of Nature (IUCN) Red List and considered a priority species in the European Union (EU ), this beetle is a picky creature: it only lives in sunny hollows of old, deciduous trees. Such habitat is key to many protected, yet lesser-known species.

“We preserve veteran trees for the sake of these species, as well as for the sake of people. Many locals are drawn to old oaks. To tell you the truth, I enjoy our work especially because we help old trees to live longer,” says Dalia. During the last five years, her team has inventoried and assessed ancient trees in selected areas across the country, 308 trees in the Neris Regional Park alone. Many trees have been taken care of and their habitats improved. The Sacred Daubų Oak is one of them. Its trunk has been fortified, wounds treated, and the area around it brightened to accommodate the needs of the hermit beetle. “We clear the thickets near veteran trees to allow more sunlight for hermit beetles,” explains Alvydas.

A Sleeping Beauty

We continue walking up a hill. The undergrowth here is dense: we climb over fallen trees, branches cracking below our feet. The air smells spicy – it must be the mushrooms that Dalia is picking with enthusiasm. “Only the mature ones are poisonous, but these are still young and good for your skin,” she explains. 

Another 2000-year-old pagan hillfort and many ancient trees later, we come across a fat dormouse. It catapults itself out of a nesting box, uses two of us as a bridge, and disappears into the hazel maze. But it is good that we found it! “Fat dormice are indicator species. It’s not just some theoretical term, on the contrary, it directly impacts our daily work,” says Tadas. Finding a fat dormouse means that the forest ecosystem is balanced. “Recently, in another part of the park, we came across a fat dormouse. For the first time! Now we know that the forest is doing well and we don’t need to meddle there anymore.” 

These rodents are simple creatures. All they want in life is to eat and sleep. All they need is hollows in old deciduous trees. But old trees are rare these days and fat dormice are struggling to survive. Red-listed in Lithuania since 1989, the fat dormouse is an endangered species with only 10 known populations across the country. Three of them are found in the Neris Regional Park. The species conservation works started here in 2005, in accordance with FSC regulations. Since then, park ecologists, volunteers, and researchers have set up over 400 nesting boxes to provide additional habitats for fat dormice. The populations of this plump rodent are monitored and the forest undergrowth is kept intact – fat dormice need dense hazel shrubs to safely move above the ground. The ongoing monitoring results show a stable population with natural fluctuations.

The future

After three hours of hiking, we bid our farewells to the Neris Regional Park. What does the future hold for its hidden treasures? As in any FSC-certified forest, in accordance with principles on environmental and high conservation values, endangered species and their habitats are protected. The same principles guard historical sites, as well as old hollow trees and their microhabitats. And there is more good news – as of 1 January 2021, a new FSC National Forest Stewardship Standard of Lithuania has entered into force. In accordance with it, reserved sample areas, such as endangered species habitats, will double to at least 10 per cent of each FSC-certified forest management area. This means more forests will be protected and safe for the fat dormouse, the hermit beetle, and other endangered species.  The Neris Regional Park will remain a haven for all, forever.