Thursday 27 October 2011

Bat Haiku

Moth wings decorate
the floor of our sheltered porch
bat in residence

This haiku of mine won the overall prize for the European Bat Weekend Writing Competition 2011. It reflects the relationship I have with one (or more) Brown Long-eared bats who we very occasionally see hanging on the wall of the covered passage that runs up between our house and our neighbours. It is the bat's feeding leftovers that more often reveal they have been using the passage, presumably as a sheltered spot to handle and eat prey

Tuesday 25 October 2011

The pull of the light

In the dark before dawn it sounds like rain falling on the window but it isn't. Instead, it is the sound of dozens of wasps flying against the glass, attracted to the bright light of the kitchen within. Looking out, I see a multitude of yellow triangles, each one with three small dots of black, below which hangs a series of black and yellow bands; a head separated from its body by the inky black background against which I see them fly.

These wasps have, no doubt, come from the nest in the attic space above the kitchen, accessed via a gap in the barge board. Last thing at night, when I let the dogs out, I can see the rigid-legged forms of the sentries that guard the nest entrance. The stragglers in, the nest shuts up shop for the night.

It must be the the timing of the light, coming as it does just before dawn, that triggers a response from the wasps. It does not happen in the dark of these late autumn evenings so there must be some form of calibration going on within each wasp, a trigger that leads to the expectation of the coming dawn and which, ultimately, allows the kitchen's artificial light to trick them into emergence. I suspect that somewhere work has been done on the emergence patterns of wasps in relation to daylight but I have not yet stumbled across it. It would be interesting to know how the response is triggered and managed. For now, however, it is enough to witness this strange spectacle.

Monday 17 October 2011

October at Kelling

The north Norfolk coast at dawn is a magical place, particularly so in October. A favourite haunt at this time of the year is the narrow lane that runs from Kelling down to the sea. The thick hedgerows here have the potential to hold newly-arrived migrants and the occasional gaps in this berry-laden screen afford views over the surrounding fields. At the bottom of the lane things open up, a small expanse of water attracts waders and duck, while short cattle-grazed turf is great for wheatears, finches and buntings.

This morning looked promising, even though the wind had moved round and there had been clear skies overnight. The numbers of less common migrants reported along the coast over recent days, including dozens of Short-eared Owls, several Bluethroat and a Radde's Warbler, not to mention that Rufous-tailed Robin, were more than enough to give the local patch some added allure.

A tit flock feeding in the upper part of the lane held at least one Blackcap but there was no sign of of Chiffchaff or Goldcrest, both of which can be encountered here in numbers on some autumn days. What was particularly evident, however, was the large number of Starlings and Skylarks passing overhead. Small groups of Skylark peppered the soundscape with their calls, while the Starlings whooshed by on hundreds of noisy wings. Trailing off the back of one of the smaller Starling flocks were two Redwing.

The numbers of Chaffinches either passing overhead or dropping into the hedgerows also suggested a movement of some size, my highest count for the patch at any time of the year according to my BirdTrack records. There were also good numbers of Goldfinches, with fewer Greenfinch and no sign of the Linnet flock that had been engaging a fortnight ago.

While the pool held 28 Teal and 4 Snipe, it was the short-turf behind the sea wall that was busy with birds. Meadow Pipits and Pied Wagtails were here in reasonable numbers, feeding alongside Egyptian Geese and a solitary Little Egret that stalked the wetter ground. Also present were three Wheatears, still moving through from northern breeding grounds.

It did feel like things were on the moving, the crossover between summer (Wheatear and Blackcap) and winter (the arriving Starlings and Redwing), and this is one of the reasons why patch birding in autumn is so rewarding. The combination of your familiarity with the site, the sense of arrivals and departures, and the chance that something rare might be about to pop out of the bramble, make for exciting birdwatching.

39 species in total, not bad for a couple of hours on this particular patch.

Mike Toms

Sunday 16 October 2011

Nature on foot


The poet Edward Thomas believed travelling by bicycle to be an unsatisfactory mode of transport, stating that it moved too quickly for him to pick out the detail he needed for his poems. Thomas was also a naturalist, his often-lyrical diaries full of notes concerning observations of the natural world and the creatures that filled it. When comes to observing nature I am in complete agreement. You cannot watch nature by bicycle; it is too much stop-start and ‘ooh, what was that I just missed?’ To be on foot gives you more opportunity to take in what is around you, to move or stop quietly, to crouch or drop to the ground. Being on foot keeps you connected, engaged with what is going on, immersed in the landscape. A bicycle denies you these things, even if you can cover more ground.

My perambulations are punctuated with moments where I simply stand and watch and wait. More often than not something will show itself, particularly if your stopping is in response to a soft call, a harsh alarming churr or a gentle rustle in the vegetation. Moving slowly and quietly also lessens the chances of you blundering into something, panicking a whirr of partridge wings or the white-rumped leap of startled Roe. More attuned to movement and noise, you can hear the approach of a mixed flock working its way along the hedgerow or the soft sound that will lead you to a hidden cricket.

There is a selfishness that sometimes accompanies my wanderings. Although happy in the company of friends, particularly when out for a day of birding, my solitary walks have their own private space, one which I am reluctant to share with the inevitable walkers who blunder about noisily on the route march from ‘a’ to ‘b’. This may be why I seek out the tracks less often walked in an attempt to engage with the natural world and escape from my own species. I am sure that some who have encountered me have thought me rude, unwilling answer the question of what’s about and share in some polite chatter.

Being on foot often allows me to side-step these encounters, as I duck behind a hedge or settle into the folds of rough ground. I sometimes speculate as to how many other creatures are also doing this, taking cover as the noisy humans approach, and wonder whether I have more in common with them than with my fellow man. Being out on foot is about engaging with the natural world and, as such, it is not so much the linear journey that I make that is important but the temporal one; time well spent and richly rewarded.

Saturday 15 October 2011

The forest in autumn


The scent of the forest has changed these last few days. The full and rounded odours of summer have been replaced by a ripeness that contains the sharp edge of decay. Autumn is upon us, the evenings are drawing in and the leaves are turning as trees retreat back into the security of their heartwood. Two Roe haunt my morning walks; feeding on the clearfell they no longer retreat but watch from a distance, marking my progress as I beat the bounds of my regular circuit. The other day I encountered a small group of Red Deer. More nervous than the Roe they slip away, heads stiff and upright, with a curious almost equine gait – Red Deer dressage.

Small parties of crossbills can be heard some mornings, their sharp, excitable calls ringing out from the tops of the pines. Blackcaps alarm at me harshly from the snowberry, like resonant pebbles brought together in anger. These warblers may be passing through or perhaps they are part of the local population into whose nests I peered earlier in the year. They will soon be gone, as nature changes her guard alongside her seasons.

The vegetation is shedding its greenery and adopting more sombre tones. One large patch of clearfell is particularly brown, the grass long dead and I suspect it has been sprayed ahead of a planned bout of planting. This is where the Tree Pipits were nesting – three or possibly four different pairs – and I wonder what they will find when they return next year. The mosaic of different-aged blocks will, however, ensure that they have suitable nesting habitat somewhere within the vast acreage of this working forest.

Every few days or so I will stumble across a plump ground beetle, a carabid, deep black and with a sheen of purple that dances across its wing cases with the changing light. These beetles seem to do well in the forest and, much like a black cat, I am warmed by seeing one cross my path. My almost daily walks around this patch of forest mean that I am sensitive to the subtle seasonal shifts in its appearance. It may be going too far to suggest that it has changing moods but this does seem a sensible way by which to describe how it feels to be in the forest on different mornings. The differing combinations of light and cloud cover, the subtle shifts in temperature from one forest block to another and, most importantly, the changing animals and plants, all influence my experience of the forest from one day to the next. Some of these changes tell me that autumn is come, that the bountiful days of summer are gone. 

Wednesday 12 October 2011

From the bottom to the top


You may well recall that I’ve been involved in something of a challenge this year. Along with colleagues at the BTO in Thetford, I have been attempting to record as many different species as possible on the Nunnery Lakes Reserve in Thetford. This is part of a challenge with RSPB and their reserve at Sandy in Bedfordshire. While light-hearted, though in some quarters rather competitive, the challenge has the underlying aim of identifying the species we have on our respective reserves, particularly beyond the large and more obvious groups like birds, butterflies and mammals. An inventory of what we have on the site is the starting point for targeted conservation measures.

Last week, we turned our attention to the offices themselves, seeking out the creatures with which we share our daily lives. The BTO offices are centred around an old nunnery and chapel; with such a long history we hoped that they might support some particularly interesting species. We have a small population of Wall Bedstraw, for example, a rare plant nationally that is found on very old walls. Our population is centred on the 12th Century ruin in the grounds that was once used to accommodate visitors and treat the sick. It is not an impressive plant, unless you happen to like your plants small, unobtrusive and best viewed from a ladder!

Perhaps unsurprisingly, the offices themselves have not turned up a great deal in the way of species new to our growing list. Last week, however, we decided to investigate some of the more tucked away parts of the building, the first of which was the cellar. I have always had something of a romantic notion of what our cellar would be like: a bit damp, rather dark and hosting some interesting spiders, woodlice and slugs. To say I was disappointed would be something of an understatement. The cellar was very dry, shockingly clean and there seemed little chance of finding anything of interest. The one creature that seemed to be doing well down here was the Daddy-Longlegs Spider Pholcus, several individuals of which hung from loose, fragile looking webs. Quite what they were living off was difficult to comprehend. Thankfully, they were not the only spider present and Iain, our spider expert, soon had several specimens to take away and identify with the aid of a microscope.

We then turned our attention to one of the attics, where there were more signs of invertebrate life. The attic was clearly the hibernaculum of choice for the dozens of lacewings that were perched on most surfaces and the presence of several large wasp nests hinted at several summers’ activity.  It was good to see so much life making home alongside us.

Tuesday 11 October 2011

Butcher bird success


The recent news that Red-backed Shrikes have bred in England for the second year running is particularly welcome. While it does not necessarily mean that the species is going to recolonise the country, it gives hope that we might see an increased number of successful nesting attempts in future years.

There was a time when the Red-backed Shrike, or ‘butcher-bird’ as it is sometimes known, was a common breeding species across much of the country. Bits of scrubby habitat, thick with bramble, hawthorn and blackthorn, were favoured for nesting, as were the newly established conifer blocks of the dry breckland soils. Victorian ornithologists were the first to note that Red-backed Shrike numbers were in decline, even though the species was still widespread as a summer-visiting breeder. During the 20th Century, however, the population collapsed and the loss of birds from previously favoured sites seemed relentless. As the numbers of breeding pairs shrank, so the population retreated to heathland habitats and their protective gorse. The last of these haunts was near Santon Downham in the brecks, where the last pair nested in 1990, the year I first moved to Norfolk.

The reasons behind the decline are thought to be linked to agricultural intensification, but egg-collecting almost certainly played a major part in the decline. The colourful and often variable eggs were particularly attractive to egg-collectors and as the birds became increasingly scarce, so the eggs became all the more prized. Although much less common today than it once was, egg-collecting still continues. For this reason, the shrikes nesting near Dartmoor have had to have round-the-clock protection. This highlights the dichotomy in our society; there are those who will selflessly give up their time to help protect and conserve rare species, acting as wardens, managing habitat and liaising with birdwatchers. Then there are those whose selfishness sees them take eggs and put the future of a species at risk, simply because they seek ownership over something that is not theirs to have.

For me, the Red-backed Shrike remains a passage visitor. It is a bird I catch up with most autumns, usually in some scruffy bit of scrub on the coast. The ‘butcher bird’ is probably all the more special to me because I do not encounter it that often. Mind you, it is such a striking and charismatic species that, even if it were once again a common breeder, I am certain that it would still hold a special place in my affections. I guess you might be wondering about the ‘butcher bird’ tag. Well, this comes from the shrike’s habit of impaling prey items on thorns and barbed wire, maintaining a larder, much like an old-fashioned butcher’s shop window.

Monday 10 October 2011

Finch disease spreads


That Britain has an important role in the wider pattern of bird movements is particularly evident at this time of the year, as many species – both rare and common – are noted arriving and departing by birdwatchers. As the first of our wintering geese arrive, so the last of our summer-visiting warblers depart. The scale of these movements is sometimes more difficult to gauge, however, particularly when it comes to common and familiar species like Greenfinch, Goldfinch and Chaffinch.

It is easy to assume that these finches, together with our other ‘resident’ species, are here all year; after all, they fill our hedgerows and woods with song in the summer and make use of our garden feeders come winter. Thanks to the efforts of licensed bird ringers we know that many of our wintering Chaffinches and Greenfinches arrive here from elsewhere, and that some of our breeding Goldfinches leave Britain for a winter spent in France and Spain.

The degree to which our finch populations are connected with those elsewhere in Europe was brought home to me recently through a piece of work with which I was involved. For several years now, I have been studying the impacts of an emerging infectious disease in finches. This disease, caused by a protozoan parasite, is known as trichomonosis and was first seen in wild finches in 2005. During 2006 we had our first outbreak, centred on the West Midlands and the Southwest of England, but in 2007 we saw it hit East Anglia. Our work has shown the disease to have reduced the Greenfinch population in affected regions by a third and the Chaffinch population by a fifth. This is the first time that anyone has been able to document a population level impact in a widespread European bird resulting from an infectious disease.

Worryingly, in 2008 a case was diagnosed in Sweden, followed by others the same autumn in Finland and Norway. Working with vets at the Institute of Zoology in London and molecular biologists at UEA, we have found that the trichomonad parasites taken from these birds are identical. This implies that the parasites arrived in Sweden, Finland and Norway via birds that had migrated from Britain. By examining bird movements we have been able to demonstrate that the most likely candidate is the Chaffinch, individuals of which migrate from eastern England to these countries come spring. Wintering Greenfinches, on the other hand, tend to migrate between eastern England and western Norway, away from where recent cases have been seen. With a foothold in these northern European populations we may see the disease emerge elsewhere in Europe, as migratory individuals mix over time. More on the disease can be found at www.bto.org/gbw