Wednesday, 4 June 2014

To catch a cuckoo

It was a chilly start to the morning. For the first time in a while the temperature reading was 3° and next to the time of 4 am once again it was a bit of an urgggh moment getting up. This time dense mist hung low, the tops of the trees poking out and reaching into a clear sky above, fading from black through midnight blue to pale blue pink as dawn slowly broke.

Arriving at the grassland heath, bounded by forest and farmland, the dawn chorus was in full swing. Skylarks, garden warblers, yellowhammers, even a turtle dove calling from somewhere in the mist beyond. The occasional tall tree and low grassy humps of what were once, many many years ago, stump rows appear out of the mist like ghost ships. Movement ahead reveals the equally ghostly forms of small sheep, the maintenance team of this grassy heath.

The grass is wet, its tops drooping under the weight of water, as we make our way over to where a tree stands alone. Here a large mesh net is set up surrounding the tree and within the centre a speaker placed. The aim? To catch a cuckoo.

With the speaker on the unmistakable call of a cuckoo booms out through the mist, followed by a bubbling sound that many may not recognise but is the call of a female. We have barely retreated, when the responses start and one then two males start calling in response. A little further away and a real female bubbles also. Out of the mist and over our heads a male makes for the tree and the speaker; perching ceremoniously on the top of our pole! The slim grey body, long tail, white chest with barring and pointed wings resembles a small bird of prey. This is of course on purpose. For cuckoo’s do not worry themselves with rearing their chicks, leaving this for other birds like reed warblers and meadow pipits who in return develop ways of recognising the cuckoo and its eggs. What has developed is an evolutionary arms race. While host birds need to keep a watchful eye for cuckoos, they also need to worry about predators like sparrowhawks that rather than parasitizing their nests are looking for a meal. The cuckoo takes advantage. By looking like a sparrowhawk it causes birds to leave the nest area for that little bit longer, giving the female time (all 10 seconds of it) to lay her egg without being mobbed.

Misty morning... spot the cuckoo

As our percher disappears from the top of the pole, a second bird comes swooping overhead and low in towards the tree, finding its path ultimately stopped by our net which with its large mesh holds onto the bird safely.

Cuckoo in the net

And that my friends is how you catch a cuckoo! (Of course you have to have a ringing licence with a mist net and tape lure endorsement). Up close he is stunning, grey-blue, and perfect barring across a pale chest, bright yellow bill and eye.  And for this guy not only is a unique metal ring added to his leg, a satellite tag is strapped on with a specially designed harness. For cuckoos (and this seems to be a recurring theme for our wildlife) are in decline and we have lost over half of our breeding birds in the last 25 years. But the picture is more complicated than that. In some areas cuckoos are doing better than in other areas, in England for example the decline is greater.

What a beautiful bird!

This is where this satellite tagging project run by the BTO, and championed of course by the BBCs Spring Watch, comes into play. Already the data is showing interesting results with the suggestion of different migration routes and the indication that weather conditions across their range have a significant impact on survival.


Where will this cuckoo go? Which route will it take? How will it fair over the next few weeks, during its migration south, overwinter and hopefully on its return? With its satellite tag will have the answers to all of these questions... soon….

Tuesday, 27 May 2014

An Owl in the Forest

To be honest even for me it was the wrong side of 4 am. Light was seeping through the forest as dawn broke, turning the misty trees various shades of grey. For the first time in a long time I could hear the dawn chorus, a cacophony of birds waking up to a gloomy day threatening on its promise of rain.

The convoy of cars made its way down the dirt track, a thick wall of tall pine trees crowding in on both sides, their tops swaying in a slight breeze. Suddenly the trees fall away, opening up into one of the many clearfell patches within the forest. Tall waving grasses and dense, thick scrub and bramble replace the wall of trees alongside the track. Looking out across the clearfell, rows of stumps line the patch, a tumble of roots and limbs of felled trees. The odd tall tree remains, standing sentry overlooking the neat rows of newly planted pine trees, merely knee high and often overshadowed at this stage by the willowy grasses that are heavily laden with moisture. 

As the convoy slows, something swoops out from the trees, catching the lead driver's eye before a sickening thud is heard from the rear of the van. The group stops and the driver gets out retracing his route. Half expecting to see a pheasant, notorious for their suicidal flights out across roads, there is surprise as he approaches to find, crouched on the ground by the side of the track, a rather stunned looking tawny owl.

Tawny owl ringed in Thetford Forest

Close inspection reveals the bird is absolutely fine if a little stunned the convoy having been moving so slowly. And while this is not the most conventional way to catch owls, we could not miss the opportunity to put a ring on this one. Very few tawny owls are ringed in Thetford Forest (not for the lack of trying). In fact this is the first free flying bird to be ringed by the Thetford Forest Ringing Group, with only chicks in the nest having been ringed before the group formed. There are however many questions about the spatial distribution and productivity of tawny owls in the Forest, and how this relates to other owl species utilising this landscape such as the long-eared owl.

This owl turned out to be a young bird, fledged this year. Tawny’s breed early, with territories established during winter, and the first eggs usually being laid between February and March. Young birds leave the nesting hole after 25 days before they can fly, hanging around on branches near to the nest for another 10 days or so. This bird was well beyond that, being able to fly, even if it was not quite so well coordinated as to avoid big moving vans….

And then with a soft swish of silent wings the owl swooped away from the road and disappeared into the darkness of the maze of tree trunks.

This was not however the reason for getting up at the crack of dawn on a bank holiday weekend…. that was to try and catch a cuckoo, something that will have to wait for another day as the birds remained stubbornly out of the net and the promised rain finally arrived.

Monday, 19 May 2014

Stars in the Garden

It was just a normal spring day in the garden, a small patch of paving surrounded by the developing green of a veggie plot, the blossoms of an apple, pear and ornamental cherry tree and the general bric-a-brac of a busy garden, bins for storage, pots, compost, wheelbarrow…

The sky above is a patchwork of cloud and sun, while a breeze ripples through the leaves of surrounding trees. All around are the sounds of birds, from the general twittering of sparrows, the song of a robin or dunnock, to the recent addition of swifts screaming overhead. But today a trill that sounds like a hoarse buzz carries above them all. The source? Recently fledged starlings begging to their parents for food.

A stunning adult female starling

Sensing an opportunity a small walk in trap is set and baited with suet pellets, a delicious and fat rich source of food for young and adult starlings alike. Retreating it does not take long for the starlings to cotton on, and before long there are not one but three birds hopping around the trap. The adults are beautiful with dark feathers which shimmer iridescent green and purple, with some yellowish spots on the back and under the wings. The males in particular are stunning, but the females too, even after raising a hungry brood, have glossy feathers. The bright yellow bill, that in winter will become dark, has a pale bluish grey base in the males and a paler yellow base in females. In contrast to their sleek and glossy parents the young are a dull brown, not until later will their moult begin and the dark, spotty plumage of winter begin to appear.

Adult male starling (blue base to bill)

Young starling

As the morning progresses there is a steady stream of birds caught in the trap. Most are adults, with the young watching and screeching their encouragement from the sidelines of the garden fence. While this noisy, gregarious and social bird may not be everyone’s favourite visitor their gift for mimicry has attracted the attention of literacy greats like Shakespere and their winter flocks are one of the most incredible wildlife spectacles in the UK. In many countries, like the USA, where they have been released starlings tend to be the bad guys, causing conflict with humans and native species. Sadly in the UK the breeding population has declined by over 80% in the last 25 years. Priorities for this species now lie in understanding more about their movements and winter roosts, to monitor their breeding and build solutions for their conservation into the development of green spaces and agriculture schemes. For urban populations more work is needed to understand the reasons and therefore possible solutions to their decline. 

So when you see a noisy gang of glossy, chattering, starlings descend on your garden, gobble up all your food in one go, don't be so harsh and quick to curse. Be thankful that here, where they are a native part of our landscape, such cheeky, beautiful birds still visit your garden. 


Monday, 12 May 2014

'Oh Happy Whales'

The day started off gloomy, low cloud and drizzle seemed to merge with a rolling, iron grey sea whose waves were crested white. Dawn was slow to break, and came as a seeping flush of grey rather than the spectacular brilliance of gold and orange. The ferry ploughed on regardless, and for hour’s one person stood on deck blinking against the occasional drizzle and buffeted against the seemingly unerring wind. Wrapped up in warm layers, woolly hat (a Granny B special) and hood up, the hours simply slipped by in a blur of waves, rain and spray. Slowly more people joined the watch, and gradually the conditions improved. The white caps melted away leaving just dark waves behind, and while at first the clouds kept a constant cover the drizzle and mizzle disappeared. Finally after four and a bit hours, something breaks the surface. Not too dissimilar to the still constant waves, but different. Staring at the spot intently something again breaks the surface. Dolphin. A second later and the shout goes up from the back of the boat also. More dolphins, riding the wake the giant ferry creates. Leaping clear of the still grey waves the dolphins reveal a bright yellow patch on their flank, a sure sign these are Common Dolphins.

Common Dolphins in Bay of Biscay

As the morning progresses towards lunch wave after wave of groups of Common Dolphin approach the vessel, heading for the bow or passing down the side before surfing the waves of the wake. At the same time conditions improve further, glimpses of blue sky start to appear in cracks in the cloud cover.

The shout of dolphin goes up again! But these are different, larger, darker and slower the group reveals itself as a pod of Long-finned Pilot Whale, surfacing close together and in synchrony, a small calf amongst their ranks.

By lunch the sun is out and the sea is calm although small waves continue to ripple across the now blue water. The whales have appeared. Out on the horizon tall jets of condensed air hang like smoke against the blue of sky and water.

The journey is coming to an end, ahead behind the hazy cloud I know the coastline of Spain and the dramatic edges of the Pyrenees will soon come into view. Around the ferry it looks like nothing has changed, except for the weather. But beneath us the seabed has undergone a dramatic transformation. From the deep dark depths of the abyssal plain, underwater canyons and jagged slopes have risen up, and while the water is still deep these provide the perfect conditions for fish and squid to flourish. And where they flourish so does the most deep diving and elusive group of all whales, the beaked whales. Once again ahead something breaks the now blue and rippling water. But there is no leaping, no song and dance, just up, breathe, and down. Against the shimmering blue the animal is dark, but close inspection reveals a brown body, paler head and a hint of scarring. Again the animal surfaces, closely followed by a second, again it happens quickly. It would be so easy to miss, but to the experienced sea watcher the species is clear, they are Cuvier’s Beaked Whales.

Cuvier's Beaked Whale

With a final fling the day is topped off with an acrobatic group of Striped Dolphin and ice cream in sunny Santander, leaving one very happy albeit tired whale watcher.

Striped Dolphin

Monday, 5 May 2014

Number 3 Oakfield Terrace

A row of four small, wooden boxes line the wall of the house, high up just under the eaves. Each looks out over an undulating patchwork of fields, woods, houses and roads, snaking across the valleys like silver ribbons. Leaves, innumerable shades of green, coat the trees of the woods nearby, while the grass of the meadow is growing long and lush. Dotted amongst this wash of green are bright yellow dandelions, and a delicate white that looks like a dusting of snow of the hawthorn bushes. The boxes are a little worn having faced the Welsh elements for years. The paint is peeling and faded, there are cobwebs under the bottom, the wood of the roof is splitting and bowing. But it is what is on the inside that counts. A small brown bullet shoots from Number 3; a short wait and a small brown flash returns, disappearing into the dark hole. Throughout the whole day both male and female dash back and forth.

Oakfield Terrace

Many birds will nest in boxes, blue tit, great tit, robin and given the right location even pied flycatchers and redstarts. In most cases you need to space the boxes out, so that each one is within one bird’s territory in order to avoid fights. There are however some species that really don’t mind, even prefer, being close together and will nest in colonies. House sparrows are one, although they prefer loose colonies rather than being one of top of the other but you need to provide options and Oakfield Terrace does just that.

A careful squint into the box reveals a tightly woven ball of grass within its confines, with a small hole near to the entrance. Even closer inspection reveals four rather fluffy chicks.

Checking the boxes 

House sparrows, a ubiquitous species that we seem to see everywhere, it feels like you cannot walk past a hedgerow, garden or house without hearing their characteristic cheeping. But this little bird, that always seems to be there, has under gone a dramatic decline in numbers, and the fight is on to understand why and to change their fortunes. Recent studies have shown that gardens are leading the fight back. Here in Wales we want to know where the birds that inhabit our garden move to; do they just stay within the confines of our garden or do they move to other gardens? Now sparrows learn quick, catch ‘em once and they ain’t gonna fall for the same trick again. Of course that means it is hard to get repeat information once you have ringed one. The solution? Colour rings. That way you can recognise individuals via the unique combination of colour rings on the leg without having to catch the bird again. So for the last few years we have been colour ringing the house sparrows in Garth, not only those caught free flying but all those raised in the nest boxes of Oakfield Terrace.

One of four colour ringed chicks

While the project is ongoing we have found that most of our house sparrows remain within the garden, with a few venturing a little further to the surrounding local area. And this kind of information is important when it comes to establishing how we conserve the population of this charming species. 

Tuesday, 29 April 2014

Fossils on a point

Peace and quiet. The only sounds to be heard is the gentle lap of water on the beach, the twittering of swallows and linnets, the warbling song of willow warbler and skylark, the muted honk of barnacle geese and the raucous calls of gulls soaring in a brilliant blue sky overhead. In either direction coarse sand and pebbles merge into mudflats glinting silvery grey in the bright sunlight. Behind me tall sand dunes with tufty grass and beyond that the soft roar of the ocean.

Spring migration had truly begun at Spurn Point, I had seen my first sand martin, wheatear, redstart and whitethroat of the year on this long spit of land that juts into the river Humber. At one end the distant yellow fields of oil seed rape, dark green mounds of trees with stark white wind turbines that are becoming a feature of our landscape just as electricity pylons did. At the other end a rather battered and bruised lighthouse stands sentry over old abandoned houses and military buildings. A life boat station remains but the families that once called this wild tip of land home have long moved on. Now the men and women working the life boat and the pilots remain on a rotation.

The serenity of Spurn Point

The spit of land is just as battered, the tidal surge just before Christmas destroyed the road that had only just been rebuilt, once again changing the dynamics of this wild landscape. Yet Spurn remains as it always has been a mecca for bird watchers and birds alike. A stop off for migrants, one of the first ports of call for birds exhausted from flying non stop over the turbulent waters of the North Sea and a known hotspot for the more rare and unusual birds that visit our shores. A small piece of quiet and natural solitude, nestled between the industry of the North Sea and the bustle of the cities.

How a landscape can change in a matter of hours. From the bright sunny skies, warm balmy breeze and constant chatter of birds, the morning dawned with a thick blanket of swirling white fog. Tree, bush and building all softened around the edges and kind of more muffled hush descending with only the odd linnet or swallow zooming overhead. And with bird watching looking gloomy Spurn reveals its other secret treasures to me. Fossils. Where cliff and beach have been worn away the remains of ancient wildlife is revealed. With cliffs and sea shrouded in fog, just the rumble of waves crashing and pebbles rolling, we scour those left scattered at the top of the beach searching for that one pebble or stone that reveals its secret so long locked away. And with the fog lifting, we find what we are looking for, ancient creatures carved in stone, preserved for eternity. 

An ammonite and Devil's toe nail (Gryphaea)

Monday, 14 April 2014

Larking Around

Only recently had the trees been felled, leaving a mosaic of sandy soil, mossy grass, patches of dark heather and tangles of twigs and branches. From the main road this seemingly barren landscape sloped up to the tall dark green conifer trees that surrounded the patch on three sides. While it may seem an extreme change this is the cycle of this forest where trees are planted and felled on a rotation. Add to that the process of returning areas to more natural grassland heath and more of such open areas can be found amongst the blocks of trees. For 100 years ago this landscape was totally different. The entire area was open with grass and heather heaths, open sandy areas, low intensity arable farming and abandoned fields. Rabbits in particular were farmed in large enclosed warrens. Following the First World War the Forestry Commission began the process of afforestation, planting hundreds of hectares of Scots and then Corsican pine to provide a reserve of timber for a country whose trees had been as ravaged by the demands of war as its people. Today the whole of Thetford Forest is a patchwork of pine plantations, broadleaved trees and heath land, and is managed not only for timber, but for recreation and wildlife.

Woodlark carrying food for its chicks

Such barren looking patches of clear fell and grassy heath provide important habitat for a number of scarce breeding birds, including the woodlark. The tufts of short grass, close proximity to bare soil and good high posts for singing, are all perfect for woodlarks to set up home during the summer.

Knowing an area is good for breeding woodlark, seeing a pair there with the male’s sweet song of melancholy notes which includes a lu-lu-lu, giving the bird part of its scientific name Lullula arborea, is one thing. Finding its nest is a whole different ball game, one of patience and knowledge. Even knowing there is a nest within a few square feet in front of you, it is still hard to see, such is the excellent cryptic nature of nest and chick.

A beautiful woodlark nest

But there nestled amongst the grassy stems is a tightly weaved nest, in which four greyish brown chicks are squeezed in. What a privilege to be allowed to approach and view such a nest, which is done under strict licence. Monitoring of this species has never been more important. Since the early 1980s the range and population of woodlark in the UK has actually increased following a severe decline, but it is still comparatively rare and its breeding range restricted. Forestry plantations form a key part of this increase, but interestingly in the Forestry areas of Norfolk and Suffolk numbers of woodlark are in decline. Understanding more about the movements, breeding success and habitat use of birds in such areas is contributing to maintaining and increasing woodlark numbers by feeding into management plans for the forest. To that end this, and other nests are being monitored from egg laying to fledging, and the chicks are being colour ringed to look at movements of birds and where they subsequently return to breed.

Feed me!

On returning these four chicks to their snug nest and stepping carefully away to a safe distance, we watch as both parent birds call with a soft ‘tlewee’ to each other, beaks full of recently foraged insects, before swooping in back to the nest. We turn to leave, happy birds, happy chicks, happy people.