Living World Jackdaw Roost Sunday 29th

I know some of you in the past have been kind enough to send in comments about the wildlife radio programmes I make, thank you. Well just to remind those who do listen, on Sunday the 29th January at 06.35hrs, there is a new series of Living World on Radio 4, beginning with a favourite subject of mine, the Jackdaw. And of course it's also available on the BBC i-player after broadcast.

http://www.bbc.co.uk/programmes/b01b8yxm

This was recorded on January 5th in Cambridgeshire. If you can remember back then, it was a stormy day, much damage across swathes of Britain. So at 5.30am in total darkness I set off into a woodland with the presenter and contributor to record a wildlife programme. The noise of the wind through the trees was deafening, it really was like a steam train passing by, only it never passed by. The stuff of wildlife recording nightmares.

The technique in such conditions then  is to 'close mic' the presenter and contributor to make sure their voice isn't drowned out by the atmosphere. That does have a disadvantage in that a lot of the atmosphere is lost. So what then needs to be done is record what's called 'wildtrack' of the atmosphere, and then in the studio mix the two together to produce something both atmospheric and listenable to.

I enjoy making all the programmes I have had the privilege to be allowed to make, but this one on jackdaws was something special, as in the evening we just witnessed what has to be one of the all time wildlife spectacles in the Natural World. I've been interested in corvids for a long time, and to be with specialists is for me just so exciting. Sadly my photographic techniques need help, as these 2 images of jackdaws taken in Dorset in 2008 prove, I never did manage to get to grips with digi-scoping!

The bittersweet taste of hail

I had my car in for its MOT today and the garage I use is on a farm in the middle of the "northern" Somerset Levels, not 1.12 miles from my house. Very handy. At 1pm the garage rang and said, all okay come and collect. So the sky was blue the clouds were white and fluffy, and I set off.

However half way into the walk to the garage it began to look very very dark over Wales, where, from where the above photo was taken on my phone, you should be able to see Sugar Loaf Mountain in the Brecon Beacons. Not this afternoon, it looked very dark and brooding, but there was a lovely rainbow developing, right over the building in the mid ground, which happens to be the garage.

I had no choice, I had to walk to the garage, so I continued. Until that is I found myself about a quarter of a mile away in a quandary. Should I stop and look at the double rainbow, knowing what was happening..........



 ....... or stop and look at the double rainbow and take some photos on my phone. I chose the latter (shame I didn't have the camera with me). I couldn't quite get the whole double rainbow in, so above and below are the result.... if you use the tree by the hedge you get the idea. 

Seconds after taking these the heaviest, and I have to say most painful, hailstorm I've been in for a long time hit me, boy did it hurt. I arrived at the garage like a drowned rat. However I wouldn't have missed this for the world, and the chance to unexpectedly see a double rainbow in front of an advancing warm front over cold air is just fantastic.

Invasive species, friend or foe

A couple of weeks ago, I had a walk around the National Trust’s Wicken Fen in Cambridgeshire. Quite a blustery day, so windy in fact I seemed to be the only visitor on the reserve. The assistant in the visitor centre showed mild surprise I wished to venture out into the reserve on such a storm lashed day, with the comment “how hardy are you?” Well I am hardy, but after an hour of being buffeted and battered as the winds hurled themselves from the North Sea and across the flatlands of this area, I decided to hurl myself into a sheltering hide for a respite.

Sitting in the hide, windblown but unscathed, in front of me were a myriad of finches and tits desperately clinging onto the oscillating feeders, and 3 grey squirrels. It was while watching the antics of these alien mammals to the British countryside that the embryonic stirrings of this blog developed. In the sunlight and the wind, these North American invaders looked stunning and completely at home here on the Fens as they grappled with the peanut feeders. It’s hard to imagine therefore the devastating effect they’ve had on out native red squirrel, as the vector of the squirrel pox virus.

But look around the British countryside and I can guarantee you won’t need to look far before finding an invasive species, anything from the “iconic British” snowdrop, to Munjac deer, harlequin ladybirds, Canada goose or even the exceptionally widespread bête noire sycamore Acer pseudoplatanus which was introduced sometime between the Roman era and the 17th century.

So what exactly what is an alien species? Biologists have identified over 11,000 alien species in Europe, but while the majority of these are not troublesome, approximately 15% are known to have some impact on the environment. Much has been written about this, but while watching the grey squirrels, I thought more on the question, how alien is alien?

Invasive species are often labelled as the greatest threat to the world’s native wildlife, derided and eradicated with a zeal and vigour. Undoubtedly some species are very detrimental to the British countryside, either outcompeting native species, or vectors of disease, but the vast majority fill a niche which happily coexists with native fauna and flora. As I’ve mentioned, come January we all look at snowdrops and think, ahh spring is on its way. But we forget that snowdrops are not native to the British Isles, and were probably introduced in the 16th Century, or maybe as far back as in Roman times.

A few years ago an attempt to tackle the issue led to the formation of a European Commission funded DAISIE project (Delivering Alien Invasive Species In Europe) and headed up via the Centre of Hydrology and Ecology in Wallingford. Its aim was to attempt to log invasive species across Europe in order to understand the problem.

http://www.europe-aliens.org/aboutDAISIE.do

Terminology is also confusing, exotics, invasive, invading, alien, but what exactly are we talking about here? It is difficult to exactly define this, but put simply, an alien species is a species brought to an area through man’s activities. In other words it hasn’t got here by normal habitat or range expansion. That seems simple enough.

But this can then be subcategorized into non problematic species, those which can exist in the wild but do little harm, so we could include the snowdrop. And problematic species, those which cause impact to ecology of the environment or have an economic impact. These are probably better known as invasive species, and the ones which often grab the attention of the press. The cute looking muntjac deer would fit this category, now widespread after being released from Woburn they have a huge impact on woodland native flora as they browse herbage in flower, thus reducing vigor, affecting nesting sites and can destroy gardens. We could also have a category of non-problematic climate change species. Currently these have no or little impact on native wildlife, but with climate change may do so, for example southern hemisphere plants which may become established in warmer climate.

A possible example of this is affecting the Breamore Marsh in Hampshire’s New Forest. In August 2009, botanist Clive Chatters discovered a small patch of Creeping Water Primrose, which comes from Central and South America. Since then 14 sites have been found in south east England. Although released by accident into the wild, it is thought as the climate in Europe warms, this plant is able to colonize areas once deemed too cold to become established. In France this plant is now a huge conservation problem.

Legislation for alien species came about with the arrival of Schedule 9 to the Wildlife and Countryside Act 1981 http://jncc.defra.gov.uk/page-1377 which makes it an offence to deliberately release or plant or otherwise allow to grow a non-native species in the wild. But across Europe there are over 50 different pieces of legislation. It is complicated so in 2008, a cross British strategy was set up, the Non Native Species Secretariat. http://www.nonnativespecies.org/. From this site I was surprised to learn that in England there are 2,721 non-native species, of which 66% are plants and in Scotland in 2000, 988 species of which 70% were plants.

The Royal Horticultural Society have long campaigned for responsible imports of horticultural flora, especially if pot grown, as vectors of fungal disease and pests. Indeed the recent arrival of the fungus Phytophthora ramorum is rapidly wiping out larch species in Britain. This phenomenon wasn’t well documented until 2009 until it was discovered in the south west of England. Indeed I was shown some of the first affected areas back then. It is thought it has arrived from horticultural stock, however the non-native and often highly invasive rhododendron is also a target. Could this fungus have a benefit in the long term in helping control rhododendron? In most British gardens about 70% of plants are non-native and the vast majority non-invasive. But care at disposal is needed.

So is there a dilemma maybe?

When is an alien species a problem, and when is it just a happenchance arrival on our shores with little effect on the native wildlife? In a recent article by Dr Thomas Ings is at the School of Biological & Chemical Sciences at Queen Mary University, London he discussed the use of the bumblebee, Bombus terrestris as a commercial pollinator. As a result the species has become established in 2 countries, Chile and Japan. Commercial growers also use the subspecies, B. terrestris sassaricus, which can hybridise with the native B terrestris. However in areas of France where the subspecies had escaped, although fears of hybridization would wipe out the native bumblebee, it seems the, the latter had out competed it for food and resources and in a study, 6 years after being found living wild, no sightings of B. terrestris sassaricus were made.

But are we conditioned to think of some species, especially the nice to look at species, as a native British species? A quick look on the internet will throw up some surprising facts. Christopher Lever, a naturalist who has studied naturalized animals in Britain for 50 years. He says the first species to be introduced to Britain was probably the house mouse that came over with Neolithic man. Hard to think the house mouse being non-native as it chomps its way through your cheese store (actually they prefer sugary items, not cheese). 

Other experts claim that the threats posed by invasive species have been exaggerated and that many native species can be equally destructive. Professor Christopher Smout, from St Andrews University, is one who recently argued this "culturally-determined" idea of native and non-native species is fundamentally flawed.

Reading the Naturalized Animals of Britain and Ireland, the general assumption is that generally it is a very bad thing to introduce an alien species outside their natural range because in most cases they damage the surrounding environment. However with current projects to reintroduce once native species into the wild such as sea eagles, beavers and red kites, are we any more at risk of creating a wildlife crisis as the control measures for these species are now often none existent?

So am I any clearer in this topic? Well yes and no. Some introduced species are obvious candidates for eradication, such as the Japanese knotweed, but if someone suggested eradicating snowdrops from the British countryside this spring, the word would spread like a carpet of Spanish bluebells in May. And the sycamore tree once seen as having little conservation merit is now known to become with age a microcosm for rare lichens and epiphytes in western Britain, as a result of its base rich bark. So the next time you’re observing wildlife at Watership Down, bare a thought for that iconic invasive species which inspired Beatrix Potter too, the rabbit, first brought to Britain by the Romans but only becoming established in the wild during the mid to late 12th Century.

Personally I adore the brown hare, certainly they’re non-native as like the rabbit they were brought over by Romans, although possibly they may have been native before the last ice age. Are they friend, foe or probably something in the middle happily ignoring the problem and just living free and adding to the biodiversity of Britain’s countryside?

In search of Jackdaws

Corvids have always been a fascination for me. But it's only since working in the radio department of the BBC's Natural History Unit that I've had some of the best opportunities anyone can ask for to get close up to some of our most intelligent birds, indeed some of our most intelligent animals in the world.

Last winter I had the privilege to visit a raven roost in Shropshire, however last week I had the pleasure to spend a day with academics from Cambridge University, looking at cognitive behaviour in corvids, specifically jackdaws. I'll post more about the programme next week. I've long known jackdaws roost in the winter in large numbers. In fact back in 2009, fellow blogger Jane from Urban Extension, posted a video of a jackdaw roost in Dorset.

So from that little embryo, this posting arose. Late this afternoon I headed off into the fields around the village. This area of Wiltshire is remote. It is this remoteness which gives the area a sense of isolation, yet as the crow flies, Reading is 50 miles away. Jackdaws however are lovers of human activity. Indeed in Britain their numbers are doing well as these resourceful and beautiful birds both forage on the detritus of human life while, nesting in the cavities and chimneys of our houses.

In the centre of the village, stately trees dominate the green. There, in the sun, on top of the trees, a hundred or so jackdaws, noisily chattering to themselves. Jackdaws are monogamous and do pair for life. Look at jackdaws and 9 times out of ten they are in pairs, flying, preening and even, though this is impossible to see food passing as a pair bonding behaviour.

So what happens in these winter roosts? From November through to about March, jackdaws and rooks gather in increasing flocks. The morning flight from a roost is different to that in the evening and it was an evening roost I sought today. From the first signs of a setting sun, so about 3.30pm in January, small groups of 50 or so birds will begin to leave their foraging areas and alight on trees. This is pre-roosting behaviour. Noisily they chatter while not really doing much. Occasionally they'll preen one and other, or fly about, but jackdaws do spend a lot of time doing nothing. Eventually as the light begins to fade, these pre-roosts begin to combine and head over to the roost site. Many roost sites may be hundreds of years old, so finding one is a piece of history. And that was my quest tonight.

Taking my cue therefore, I followed these black birds, down the aptly named Dark Lane in the direction they were heading. It was not long before I found a sizable jackdaw and rook flock, probably five or six hundred in total.

Around the countryside, many trees were sprinkled with black confetti, black chattering confetti to be accurate. Now at this point, these flocks should all begin to combine until one super flock develops, something akin to the well known starling murmerations. What is different and extraordinary with this jackdaw and rook flocking, is precisely that, it is two different species working in unison, both flocking and displaying together.

Tonight though, this didn't happen. On two fields agricultural operations were going ahead. Maybe this changed these birds behaviour. Certainly the mixed corvid flock took full advantage of the newly turned soil. Indeed so did I. That wonderful wet earth aroma drifted across the countryside, so while I stood watching the birds, the farm machinery and the developing sunset, my senses took my mind back to a distant, primeval countryside, where for hundreds of years these birds have been roosting in these same woods, watched over by countless agricultural workers I'm in no doubt.

More birds came in and took advantage of the direct sowing, even more gathered in trees behind me. But where do they roost I wondered?

By now the sun was setting rapidly, giving me a brief opportunity to take a scenic photograph or two of these wonderful skeletal trees dotted around this Wiltshire landscape.

As the sun dipped below the horizon, the jackdaws and rooks headed in a westerly direction. I followed across field after field. Above me a lone song thrush sang it wonderful piercing song, each phrase repeated. Many's the time I have heard a song thrush in full voice, never to have found it. Which is strange given that they usually sing a-top a tree, but that song is for another thrush, and not for me.

And then as I waked towards the sunset and the developing flock of corvids, they about turned and headed back east. Loose flocks drifted like black paper billowing out of a fire, across the now orange sky, the chattering of the jackdaws far out competing the relatively more silent rooks. As they flew back to where I had come from, it was obvious that pairs flew together. Obvious too the size difference between rooks and jackdaws.

Why rooks and jackdaws spend so much time together is a bit of a mystery. Protection from the bigger rook could be one reason for jackdaws to combine their numbers. It is possible the larger rook assists the smaller jackdaws by probing deeper into the soil and allowing the jackdaw to feed on the spoil of the forage. But we just don't know. I like mysteries, mysteries make us quest for knowledge, search for experiences and as I did this evening, venture out in cold conditions to allow my senses to be enveloped by the winter night drawing in.

But for the roost, I do not know. After heading east again, these birds kept flying. Jackdaws can forage up to 30 miles from their roost site, so although I thought I had a good idea where it was, they fooled me and escaped the camera's lens. There is always tomorrow. That is the fun of wildlife watching. I may have lost the roost, but I gained a brown hare hunkered in the middle of a field; I gained a flock of over 100 fieldfare, and I gained a wonderful spectacle of 40 or so lapwing rising from the shadows and heading east in their distinctive flap flap flight. That is wildlife watching at its best, the unexpected often outshines the planned or expected. Which is how this final photograph came to be. Walking back along Dark Lane, the colours intensified, the silhouetted trees grew taller, and maybe just a little bit more menacing. One last opportunity for an image of a wonderful dusk in deepest Dark Lane Wiltshire.

Twelfth night

Well it's gone. After nearly 3 weeks being gazed upon and the focus of our attentions over the festive the season the Christmas Tree has been taken down.

Twelfth night has always been significant for me. I'm not sure why, but on the evening before the tree, and decorations, come down, I often sit quietly with just the tree lights lit thinking about the last few days, Christmas, the New Year ahead and generally just absorbing the peace and quiet of this time in January, a respite from the hustle and bustle leading into Christmas itself.

According to the Shorter Oxford English Dictionary, Twelfth Night is described as "the evening of the fifth of January, preceding Twelfth Day, the eve of the Epiphany, formerly the last day of the Christmas festivities and observed as a time of merrymaking".

However there is often confusion these days, whether it is the 5th or the 6th. I've always said the 6th, but maybe I'm a day overdue.

Like many people I love putting the decorations on the tree. Most are now getting on in years and have sentimental value, either remembering when first bought, or recalling past Christmases. This one above was a house warming bauble from my parents in 2009, after moving into my current house on December 21st. I didn't have a tree that year, last year I had pneumonia over Christmas so this year is the first year it has been used and enjoyed.

This chap was bought in Germany in 2000. He's one of 6 soldiers. I was on an overland holiday to Italy and stopped off near the Rhine. In the now long forgotten town there was a permanent Christmas shop, so he, along with a rotating decoration powered by candles, was bought. Sadly the first time I lit the candles on the latter it busts into flames and was no more. Most entertaining.

I love gnomes, don't know why. Not gawdy plastic gnomes, but proper woodland gnomes which are quite special to me. Back in 1995 or 1996 I saw a box of 6 gnome decorations, 2 on snails, 2 on mushrooms, 2 on Christmas baubles. I've never seen anything like this before or since and they've treasured. The only down side is they're made of pottery so weigh a lot, hence they're attached to branches in the middle of the tree.

Every year I like to buy one new decoration to add to the collection, however this year I've added 2. On the drive up to visit my parents just before Christmas, we stopped at the National Trust's Clumber Park in Nottinghamshire, for a break in the journey. I have begun to stop there as it is about half way between home and parents, just off the A1, and the food is infinitely better than on a motorway service station. This year after an enjoyable soup and a roll, we noticed the shop had a sale on, which was handy as we'd still quite a bit of Christmas shopping to do, stocking fillers and the like. So spying this white owl at half price, he had to be added to the tree decorations this year.

But then when standing in the queue I spied this bicycling Santa. I love quirky things, and so, as he was also half price, in the basket he went.

So there we go. In another 330 days I'll be getting the decorations out of the loft again, but for this year I'm going to enjoy them one last time in this posting.

NHU Bird Cup - final day

Well I've finished. It's 2.40pm on a very wet New Years Day here in Wiltshire, so I'm hanging up my Bird Cup binoculars for the last time. My final score, 96. Sadly I didn't make the 100 which was my target, but I feel happy with failing by only 4. Not bad too as over 80% of the birding has been inland, a lot of miles have been walked on farmland and woods away from wildlife reserves, and my one day at the coast, at the RSPB's flagship reserve at Arne in Dorset was thwarted by rain and thick fog, so any seawatching at Portland was out of the question.

After a cracking 49 on Christmas Day, the remaining 47 have been a hard slog. But that's always the thing with bird cups or races, a total soon tallies up, then slows down dramatically.

So here's how the remaining 47 were found;

Boxing Day; Chew Valley Lake, Avon - Grey Wagtail, Pied Wagtail, Pochard, Little Grebe, Goldeneye, Treecreeper, Goldfinch, Shelduck, Moorhen.

December 27th; Ditcheat, Somerset - Coal Tit

Steart Point, Somerset at dusk, Song Thrush, Golden Plover, Redshank, Curlew, Dunlin, Short Eared Owl.

December 28th;Sand Bay, North Somerset - Linnet, Great Black Blacked Gull, Stock Dove, Bullfinch, Reed Bunting, Greenfinch.

Coate Water, Swindon - Goosander

Wexcombe Down, Wiltshire - Red Kite, Sparrowhawk, Red Legged Partridge, Grey Partridge, Hen Harrier (Ringtail).

December 29th;Non birding day at the Hillier Gardens in Hampshire - Mistle Thrush (2 feeding on mistletoe which was just perfect) and a Nuthatch

In the evening sitting in a tree near village of Oxenholme, Wiltshire - Tawny Owl

December 30th;Wet and soggy day at RSPB Arne - Marsh Tit, Green Woodpecker, Oystercatcher, Pale Bellied Brent Goose, 2 Dark Bellied Brent Goose, Bar Tailed Godwit, Great Crested Grebe, Red Brested Merganser, Skylark, 600+Avocet. I and another birder also thought we heard a Dartford warbler, but we couldn't locate it, so I didn't count it.
Woodcock - flushed from a track at dusk at Wexcombe Down, Wiltshire.

New Year's Eve - Woods around St Katherine's Church, Bedwyn Common, Willow Tit and then a Barn Owl at 10pm in the lanes near Little Bedwyn in Wiltshire.

New Years Day - non birding walk along the river Kennett in Wiltshire near Ramsbury, provided the last 2 birds, a stunning Kingfisher and in amongst 50 or so Canada geese, a single barnacle goose (presumably feral but that counts).

Great misses - no snipe seen in 8 days despite being in wet meadows a lot of the time, so getting a woodcock was even more of a weird fluke.

Great hits - well, the barn owl last night was fantastic. This area is prime habitat for them, but it had been raining all day but by 9pm it had stopped. I just had a hunch to go out and if nothing else enjoy the drive around the empty lanes here before returning to the fizz at 12. And there on a fencepost in classic pose, a barn owl. Absolutely fantastic end to 2011.

It's been a funny 8 days because the weather has been so mild, wet and grey, colder and sunny conditions may have got me to 100, but hey, it's just a bit of fun.

HAPPY NEW YEAR TO YOU ALL............