Bullfinch

The small copse is a mass of thorns and bramble, with a few taller trees providing a degree of elevation that seems to favour the finches and thrushes that attend the small feeding station that has been set up here. The copse is practically an extension to the neighbouring wood but it has a very different character. While the wood is wet, a small spring feeding a clear stream that flows the short distance into the river, the copse is on higher ground, dry in nature and with different trees and shrubs its constituent parts. I often stop here on my way home from one of my walks, the feeding station attracting a mix of birds and affording good opportunities to view them at close range. This morning, the chaffinches, tits, blackbirds and thrushes are joined by redwings (which gorge themselves on the few berries that remain) and two bramblings (close relatives of the more familiar chaffinch). However, it is the bullfinches that I have come to see, since this is the one spot locally where you can practically guarantee seeing these delightful finches. Sure enough a male bird is present, his pinky-red breast and cheeks striking when viewed against the dark bushes behind.

The Bullfinch has something of a shy and retiring nature, a bird of deciduous woodland or scrubby corners, which occurs at low density across much of Britain and Ireland. The unobtrusive nature of this bird is matched by its soft call, which is easy to miss, and its equally soft song, the latter containing some notes that are so soft as to be barely audible; this has the effect of making the song appear somewhat hesitant and punctuated with gaps. Seemingly out of keeping with the soft and rather understated call, the Bullfinch is actually a rather fine mimic. For this reason Bullfinches have been long-valued by cage bird enthusiasts, with some birds taught to mimic whimsical tunes by their owners. This habit was once particularly fashionable in Germany, where large numbers of birds were trapped to meet a growing public demand.

The numbers of Bullfinches present in Britain have been in long term decline, prompting the species to be added to the ‘red-list’ of birds of conservation concern. Given their current predicament it is hard to imagine that they were once regarded as a serious pest of commercial fruit trees, something which led to licensed control measures.

There is no sign of the female today but I am sure she will be somewhere within the thicket of thorns. Bullfinch pairs are long lasting and it is reassuring to be able to visit this particular copse to catch up with these delightful birds so readily.

Snowscape

Fresh snow transforms the landscape, bringing with it a shift in my mood and I am quick to leave the house to walk favourite haunts under these new but temporary conditions. My first stop is the forest. Just as dawn breaks I christen its immaculate carpet of crisp white with the crunch of my footfalls. The dogs love the snow; it is an edible carpet that tickles their ever-inquisitive noses and they seem more playful than ever. The lines of dark conifers become part of an optical illusion. Last night’s snowfall has coated their trunks with thin vertical brushstrokes of white, covering a narrow part of the darker trunks. In the half-light of dawn these lines of white become the trunks themselves, shrinking these great trees into mere spindles, now top heavy with snow.

The snow reveals the passing of other creatures; deer, rabbits and even a fox have crossed my path overnight, animals whose presence would have otherwise gone unnoticed. Still, mine are the first human first steps on these trackways and for now this landscape is mine.

Two hours later, and with the dogs now drying off at home in the kitchen, I am out again, down to the lakes to see if the cold weather has brought more duck in from further east. Now that the day is properly awake, the brightness of the seamlessly blue sky and white landscape combine to produce a light that is more intense than that of mid-summer but less saturated with colour. Dark branches of the riverside alders stand silhouetted against the sky, each branch supporting a line of fresh snow. So still is the day that even the rambling, wire-like, stems of the hops which grow wild here carry their own carpet of snow. One piece of stem, which loops about itself, supports nearly two inches of snow, a wafer-thin column that defies gravity.

Small flurries of snow fall from the tree-tops as a small party of siskins works its way ahead of me, feeding on the alder cones to the accompaniment of shrill but chatty calls. Larger showers of snow are dislodged by cumbersome woodpigeons that explode from their roosts, alarmed by sudden my arrival, and these drift down like a fine mist to settle cold on my face. Soon I am away from the river and out of the wood, skirting the lakes. I am no longer alone; two fishermen pace up and down near their rods to keep warm. Have they been here all night? I move further down the reserve, heading towards the quieter lakes where the wild duck rest undisturbed. The stillness remains, punctuated only by duck calls and the crunch of my footfalls on fresh snow.

The vikings are coming

Hedgerows that a few short weeks ago were plump with berries are now empty, stripped by large numbers of wintering thrushes, including many blackbirds, together with song and mistle thrushes. Snow, thick on the fields in the run up to Christmas, added to the demand for energy-rich berries, pushing redwings and fieldfares off the fields to feed upon the now dwindling berry stocks. Many of the redwings will have been here since late autumn, arriving at night, their nocturnal migrations softly broadcast through their characteristic flight calls. In the mild weather of November and early December these birds will have fed on earthworms and other invertebrates, initially in farmland but later within the more sheltered woodlands where the effects of overnight frosts are greatly reduced.

Redwings are extremely vulnerable to prolonged periods of cold weather and, unable to find food, they quickly use up their limited energy reserves. In the coldest of weather they can suffer very high levels of mortality, something that may explain why the birds may push southwest from Britain into Spain and Portugal if the British Isles are hit by a pronounced cold snap. The birds will also turn to gardens, moving in to exploit any berries remaining on a cotoneaster or holly. Here they will face competition from the larger (and hence dominant) blackbirds and mistle thrushes. The redwings may also make use of windfall apples.

The arrival of these birds often triggers a run of phone calls to the offices of the British Trust for Ornithology (BTO), with people unsure of the identity of these small thrushes seeking advice. Slightly smaller than a song thrush, the redwing is an altogether darker looking bird, streaked below and dirty brown above. The key features to look for are the bold white stripe above the eye (the supercilium) and the red ‘staining’ under the wing which just extends down onto the flanks. Be aware that the song thrush has a rusty-buff underwing that might cause confusion.

Redwings are nomadic in their movements, to the extent that a bird wintering in a Norfolk garden in one year, could be wintering in Italy or Greece the next. Our birds come from two distinct breeding populations, one in Iceland and one extending from Finland through into Russia. Those from Iceland tend to winter in Ireland and northwest parts of Scotland, while those from Finland and Russia tend to winter in the southern half of Britain. The two ‘races’ are subtly different from one another, the Icelandic birds tending to be larger and darker. Interestingly, the species has bred in Britain on occasion, typically when populations elsewhere have been at their peak, something that is no longer the case.

Winter moths

The freezing temperatures and snow of December should, you might have thought, have put a halt to the activities of most insects. However, one species of moth was seen at our window on several occasions over the Christmas period. This was the appropriately named ‘winter moth’ Operophtera brumata, a species whose name may be familiar to gardeners and fruit growers as a pest of apple trees. The grease bands seen around the trunks of apple trees are an attempt by fruit growers to reduce the impact of this species on the apple crop.

The winter moth is one of a small number of geometrid moths that are on the wing throughout the winter months. It is only the males that can be truly said to be on the wing, as the females of these species are flightless. Some authors describe the females as wingless but this is not factually correct since the females have wings but these are mere stubs. Interestingly, the pupal stage of these moths sports full-sized wing cases but these remain unfilled in female pupae. This might suggest that the loss of functioning wings in these females is a relatively recent evolutionary phenomenon. Male winter moths may sometimes carry the much smaller females in flight during copulation but females are more usually encountered climbing up walls or tree trunks.

The male winter moth is a rather drab creature, with soft brown tones and little in the way of patterning. In fact, it probably looks how most people would imagine a moth to look, even though many moths are brightly coloured. The single generation of adult winter moths is on the wing from October through into January, the resulting eggs not hatching until April. The timing of hatching is critical, since the caterpillars that emerge depend upon the flush of new leaf growth for food. By mid-June the caterpillars will have dropped to the ground and entered the pupal stage in which they will remain until the following winter.

Other moths may also spend the winter in the adult form but, unlike the winter moth and its geometrid relatives, these moths hibernate, favouring sheltered locations like tree cavities where the temperature is more even. Some of the winter-active geometrids have been shown to have amazing capabilities when it comes to freezing temperatures. The author and moth enthusiast Roy Leverton once described how he found a pale brindled beauty that was trapped in a pool of melt-water that had refrozen. Roy carefully chipped away a small chunk of ice, still containing the entombed moth, and took it home. Once the block and moth had thawed out, the moth flew off, seemingly unharmed by the experience. Now that’s a useful skill to have!

The eye of the beholder

Jeremy Mynott, in his excellent book ‘Birdscapes’, explores what it is about particular birds that draws them into our affections. He does this by exploring what it is that we see (or hear) in a bird which then stimulates some response; ultimately, perhaps, marking the bird as one of our favourite species. Is it the ‘beauty’ of the bird or its song and, if so, exactly what qualities are we using to define such ‘beauty’? For some birds it may be their colouration, the brilliant colours of a kingfisher perhaps, or the intricacy of their song. For others, it might be some association with a particular place or habitat – the confiding robin that accompanies your gardening or the rich beauty of the nightingale’s song heard on a still summer evening.

I’ve been pondering Jeremy’s words a fair bit over recent weeks, playing around with my own list of favourite birds and then asking myself why particular species are on the list and why others remain absent. I realised that it is a very personal thing, that certain species may be on my list but would not feature on the lists of most others. Then again I’m sure that some species will feature on many lists. The barn owl springs to mind but perhaps for different reasons; I worked on barn owls for a number of years and had many memorable encounters with these birds.

One bird that is on my list but probably not on yours is the smew; a diving duck that belongs to a small group of ducks known as the sawbills. The smew is not a colourful bird; it is predominantly white, with delicate black and grey markings but it is exquisitely and artistically beautiful. I cannot look at a male smew without imagining that a highly skilled draughtsman has pencilled the black markings in. For me, the smew has other qualities. First there is its scarcity. As a young birdwatcher, the smew remained a tantalising prize, a rare winter visitor to a few large waterbodies beyond the reach of my bicycle. Even now the smew is not a bird that I see every year, which means that when I do see one I relish the encounter even more. The few birds that arrive here each winter are mainly scattered across southeast England and East Anglia, with the southern margin of the Cambridgeshire Fens more likely to be favoured than either Norfolk or Suffolk. Then there is the name ‘smew’, which has something of Dr Zeuss about it; light, comical and perfectly suited to this bird, with its black eye mask and sixties quiff. There are some about this winter and I might just go to see one.

Winter gulls

A number of Thetford residents provide handouts to the local ducks and geese, a pattern no doubt repeated in other conurbations across the county. At this time of the year the regular recipients of these handouts, the local Canada geese, mallards (many of dubious parentage) and the solitary muscovy duck, are joined by several dozen black-headed gulls. These delicate gulls are generally more wary, usually keeping a respectful distance from the feeding frenzy but they will take to the air to drop in and grab a piece of unclaimed crust. Just occasionally one of the gulls can be seen sporting a metal ring and, with patience and a supply of bread, it is often possible to read the ring number. Just the other day, one of my colleagues did exactly this, the presence of a German-ringed gull on the river.

It is easy to dismiss black-headed gulls, especially as so many people lump the different gull species together under the name ‘seagull’, but they are worthy of our attention for many different reasons. Black-headed gull is the species most often associated with Man; they can be found on sports-fields, around rubbish tips, following agricultural machinery or scavenging scraps in our towns and cities. Populations of these small, delicate birds occur across most of Europe, their breeding range extending across Asia and even reaching parts of North America. During the winter many of these birds move away, taking them as far south as West Africa, India and Mexico. Most of those breeding in Britain remain here but some move into France and Spain. As the German-ringed bird shows, our wintering population in swelled by the arrival of birds from Scandinavia and the Baltic, making this the commonest gull in the county during the winter months.

The arrival of these winter visitors begins gradually, from July, with the arrival of birds from breeding colonies in The Netherlands. The main arrival occurs during late September and early October, with peak numbers present during January and February. Britain provides an ideal combination of milder weather, an abundance of feeding opportunities and suitable roosting sites; the latter present in the form of large inland waterbodies on which the birds congregate from mid-afternoon. As well as taking scraps, the birds will feed on soil-dwelling invertebrates, especially earthworms, which may either be revealed during farming operations or taken from pastoral land and playing fields. Watch a group of black-headed gulls feeding on an area of short turf and you may see them ‘puddling’, moving their feet up and down to draw earthworms to the surface.

While it is easy to dismiss these birds because of their familiarity, there is more to them than you might first imagine.