When was the last time you saw a bumblebee? For me it was last Wednesday but the expected answer would surely be ‘late summer last year’. I wonder... have you too noticed some unseasonal events occurring in this particularly mild winter? In the same week, a swallow was photographed in Essex and no less than five species of butterfly were recorded in Hertfordshire!

Of course, if you are into making lists these records give you a chance to get ahead with your year list of sightings, but I can't help feeling a little unsettled by these 'unnatural' natural occurrences. We look forward to the march of the seasons, the return of the swallows in spring and of butterflies in summer! The natural world often feels eternal with trees hundreds of years old that stood in times very different from ours, and rivers and streams whose water has perhaps seen the sea many times. There is security and comfort in the enduring qualities of the natural world.

There have been many occasions in my own life when I have literally 'escaped' to nature to regain perspective and restore my state of mind. Growing up with an ill mother and complex family history often left me as a teen frustrated and at my wits end. Spending time out walking in nature, whether in the wilds of Cornwall, the gentle hills of Dorset or the more intensively worked countryside around St Albans, reconnected me with something greater than myself and altogether reassuringly stable, despite the uncertainties of life. I was saved time and time again from sinking into depression by the irrepressible joy and vitality of nature.

Ironically the one certainty in nature is change. Nature's stability lies in its dynamism and that is also its greatest therapeutic quality. Depression is a closed world, a finite one where only endings are visible and the mind is trapped in a destructive infinite loop. Change is not possible to the depressed mind and only hopelessness remains. The experience of nature is quite the opposite with endless possibilities and surprises round each corner. Nature is a mind-changer and a hope-giver.

Joe Harkness has talked lucidly about his ongoing battle with mental health in his excellent book Bird Therapy and how the experience of nature and in particular birds opened up a pathway of hope and healing for him. He relates his discovery that the hobby of birdwatching perfectly embodies the 'five steps to wellbeing' advocated by mental health charities such as Mind.

The first step is 'to connect', then 'to take notice', 'to give', 'to keep learning' and 'to be active'. Even a short walk in the countryside provides an opportunity to take at least four out of five of these steps. Nature has a way of grabbing our attention - maybe the unexpected flash of a kingfisher's blue along a river or the exquisite beauty of a flower - and it's not long before we are engaged, lifted out of our finite world (if that is where we are), and opened to other worlds and other thoughts.

We find we are not alone in our discoveries and that others have also heard the noisy song thrush or noticed a particular flower in the woods.

I love reading Mark Cocker's excellent diary of his forays into his local parish in Norfolk-Claxton. It is a collection of daily observations, mostly just a short walk from his home, pondering the wonders, variety and complexity that he encounters every day. What amazes me is how often our observations coincide, sometimes to the day.

CS Lewis is often attributed with saying, "We read to know we are not alone" and Mark Cocker, though I have never met him, is nevertheless a companion on my own rambles through nature. Despite the disturbing observation of a bumblebee last week I took comfort in the fact that Cocker's first entry in his follow-up A Claxton Diary (published last year) records the same experience - a bumblebee on New Year's Day 2016!

He says, "we sense instinctively that a midwinter bumblebee can be neither random nor without meaning" but in sharing he reaffirms nature's ability to surprise and connect us together - and we are the much better for it!