As Japan begins to cautiously reemerge from domestic travel restrictions due to the ongoing threat of coronavirus, I was delighted to head to the beautiful mountain resort town of Karuizawa for my first reporting in many weeks. Located in the shadow of Mount Asama in north-eastern Nagano Prefecture, Karuizawa is known as the premier spot for Japanese holiday-goers, both for its spectacular forest scenery and impressive range of wildlife.

A pleasant twenty-minute walk from Nakakaruizawa station is the Karuizawa Wild Bird Sanctuary, where a non-profit organization called Picchio (Italian for "woodpecker")has been working to manage and protect the local population of Asiatic black bears, funded by expert-led wildlife tours of the surrounding forest.

Today I would be joining two such tours - the first offering a general introduction to the local flora and fauna, while the second would be in pursuit of one the area's most unusual nocturnal inhabitants. As with many sites open to the public, Picchio have been taking a proactive approach to coronavirus safety, requiring all participants to take a temperature check and wear a mask in order to take part.

My first tour began in the early afternoon and lasted a little over ninety minutes, taking us on a loose circuit of woodland paths as our guide highlighted all sorts of points of interest, allowing us to see, hear, touch and even smell traces of wildlife around us.

Amongst the trees and thick undergrowth, we encountered a wide range of plantlife starting with the tsurifuneso (touch-me-not), whose green leaves hide delicate pods that explode in a puff of tiny seeds when touched to protect them from caterpillars. We also found mulberry trees whose sticky, sweet black fruit are a popular source of food with local animals, and sansho (mountain pepper), whose little pods have a sharp, citrusy bite and are commonly used in eel dishes and yakitori.

Signs of insect life could be found everywhere, from weird and wonderful caterpillars to alarmingly large ants. Producing a light net, our guide was able to expertly catch first a large dragonfly, then a green-veined white butterfly that we soon discovered smelled strongly of lemongrass. Hidden in the leafy undergrowth we also found leaves, stripped and rolled into tiny cylinders by weevils to cocoon their eggs.

Throughout our walk we could hear the sound of birds singing around us, but even with our borrowed binoculars the thick summer foliage made them difficult to spot. I was eventually able to snap a hiyodori (brown-eared bulbul) as it alighted briefly on a nearby branch, and our guide was able to identify an especially melodius voice as belonging to a kibitaki (narcissus flycatcher).

While not lucky enough to spot any larger animals, we were able to find trails in the undergrowth, serow prints and claw marks in the bark of a tree climbed by a small bear.

One last and quite unexpected highlight of the first tour was bumping into Elf, a gorgeous two-year-old karelian mountain dog, one of several kept by Picchio to assist in tracking bears, alerting staff to their presence or if necessary frightening them away from paths open to members of the public.

With a couple of hours to kill before the start of my second tour, I made my way along a wooded path to the nearby Harunire Terrace - an attractive row of modern lodge-style buildings housing cafes, bakeries and souvenir shops set alongside the Yu River. Here I enjoyed a very tasty cup of coffee and took a few moments to appreciate my beautiful forest surroundings.

With the light beginning to wane, I made my way back to the Bird Sanctuary for my second tour - this time to catch a glimpse of one of the sanctuary's most unusual inhabitants - the musasabi or giant flying squirrel.

Measuring around 80cm from nose to tail, these amazing creatures are equipped with a wing-like web of skin from their fore to rear legs, allowing them to glide through the air like little parachutes. While it is usual for them to travel a distance equal to two thirds the height of their starting point, some have been known to travel further, with the record standing at an incredible 160 meters!

With the musasabi only emerging from their nests to forage around 30 minutes after sunset, we waited until just before last light before setting out with our guide to an area near a local resort hotel where a box had been placed for them, designed to mimic their natural nesting sites in tree hollows. As we quietly approached the box, our guide produced a portable monitor and connected it to a camera mounted inside the nest, revealing one of the creatures curled into a ball, just beginning to stir as the darkness set in.

Over the next few minutes, the solitary musasabi gradually uncurled and began to groom itself, before showing just enough of its striped face to peep through the opening, a step it cautiously repeated several times. When it finally emerged, it paused on the roof of the box for just a moment before darting to the treetop, almost too fast to see, before extending its wings and swooping into the darkness. The movement lasted just two or three extraordinary seconds before the creature disappeared into the darkness.