Monthly Archives: April 2011

April birdwatch

The activities of the birds in my garden have changed significantly in the last 2-3 weeks. Until then I was seeing multiple blackbird, robin, starling, goldfinch, chaffinch, dunnock, blue tit, great tit, collared dove and house sparrow with less frequent visits by long tailed tit. Since then a pair of wood pigeon have virtually taken up residence in my back garden and hoover up all the bird food before the smaller species get a look in. There is still the occasional dunnock and blackbird on the ground and much less frequent visits by blue tit, robin, starling and chaffinch but the goldfinch have all but vacated. This is interesting because when I’m outside I regularly see and hear groups of goldfinch in the trees around the garden but something seems to be keeping them away from my feeder.

My friend Chris told me he had a songthrush rearing chicks in a nest in a tree in his garden and she fledged four youngsters last week, which is very early in the year, so hopefully she’ll fit in another brood this year. But his garden has been subject to the attentions of a sparrowhawk in recent months so he was worried it would catch the fledglings, but clever use of carefully placed hanging bamboo canes has successfully deterred the hawk and all four fledglings seem to have successfully flown the coop. Songthrush 4, sparrowhawk nil.

Continuing with garden birds, last week it occurred to me that the fat balls hanging in my front garden were requiring replenishment rather more frequently than usual so I guessed the nesting birds were feeding more often. The reason turned out to be rather more amusing:


One of the local rooks has worked out that these are edible…

…and that it can reach them. And it takes alot of fat ball to fill a hungry rook!

Slightly further afield in the hedgrows and scrub bordering the farmland around Histon it’s a very good time to survey the local wildlife. As I mentioned in a previous post many species of wild flower now including forget-me-not, yellow archangel…


Forget-me-not

Yellow archangel – Lamiastrum galeobdolon, this variegated version is an invading subspecies ‘argentatum’

…herb robert, cow parsley and periwinkle are all in bloom and lining the paths through the countryside filling them with a palette of colour.

And in the fields, trees and bushes there is an abundance of birdlife:


Corn bunting perched in the midst of a field of oil seed rape

The countryside is ablaze with the yellow of rape flowers right now and just occasionally a photographic opportunity such as this one arises. I’m not particularly keen on the vast swathes of rape but it created a lovely backdrop for this corn bunting which are becoming increasingly uncommon.

It’s not unusual to see and hear bullfinch in one patch of scrub near the church in Histon, which is a regular destination for my birdwatching outings. That makes me very happy because I used to see them all the time when I was a kid in the 1970’s but since the 80’s they seem to have been persecuted to near extinction in alot of the UK because of their fondness for the green shoots of commercial fruit trees. They are still fairly elusive but I managed to get this photograph of a male (just!):


Male bullfinch – the female has similar markings but they are not pink she is more pale grey/brown

And in the same field as the bullfinch linnet are in residence, as are willow warbler, chiffchaff and blackcap which have now returned from over wintering in Africa:


Blackcap male

Chiffchaff

…as are whitethroat:


A female whitehroat, one of a pair patrolling a patch of brambles in the middle of the field

This field is an amazing place, I reckon it’s approximately 10-12 acres and it comprises several habitats including open-ish grass, it’s sorrounded by some old established trees: oak, ash and horse chestnut with hedgerow joining up the old trees consisting mainly of hawthorn and in the field itself there are alot of ash and other saplings and some large patches of bramble. Consequently it provides good supplies of food and cover for nesting for a number of different species. Green woodpeckers can be constantly heard yaffling to each other:

…and birds of prey including kestrel, sparrowhawk and buzzard are regularly in the skies above. The green woodpecker are there all year round and are usually hidden in the grass so I’ll flush one off the ground only for it to disappear into a tree too distant to allow a photograph. So this is about the best image I have of one. Most of the common or garden birds are regulars here too, house sparrow, dunnock, blue tit, great tit, long tailed tit:

…and chaffinch

…blackbird, songthrush, rook, crow and magpie are all present every day. So a small area of mixed scrub an the edge of the village supports a wonderful number of our birds.

There’s lots to see by simply look up in the village too. On the way back from the playground in Impington with my kids today we cycled along a road under a tree as a jay emerged from a silver birch on the other side of the road and landed in the tree a few metres over our heads. We all stopped to look at it and marvel at it’s amazing colours, and it looked at us for a minute or two before flapping off higher up the tree.

Advertisements

Local Lepidoptera

The class of insects known as the ‘Lepidoptera‘ is the one that encompassses moths and butterflies. Many species of both have emerged from hibernation and can be seen aplenty in gardens, parks and in the countryside.

Speckled wood (Pararge aegeria) and orange tip (Anthocharis cardamines) are abundant in scrub and hedgerows.


Speckled wood butterfly warming up on a bramble leaf

The speckled wood is an interesting butterfly for a couple of reasons. It has a north/south colour variation where  more northerly individuals have  whitish spots and more southerly ones have orange spots. The other unique feature of this species is that it can overwinter as both a larva and a pupa resulting in adults emerging all the way through from Spring to Autumn.

I don’t have a good picture of an orange tip as they are very difficult to catch stationary. I watched one sat on a cow parsley flowerhead for several minutes last weekend, but of course I’d left my camera at home. The males have a 40-50mm wingspan, creamy white upper parts with big orange patches on the wingtips which alaso have a black margin. Underneath they have wonderfully intricate green lacework which makes highly effective camouflage. The females don’t have the orange tip, which is thought to be a warning to predators that they are unpalatable, but they are easier to see on food plants as they are not busy looking for mates in the same way the males are. Photographs to follow, hopefully!

A few red admirals (Vanessa atalanta) have been spotted by me in Histon so far this year, although not more than two or three, but in the last two weeks large numbers of small tortoiseshells (Aglais urticae) and holly blues (Celastrina argiolus) are flying around in the hot sunny weather.


Red admiral on a bramble stem


Small tortoiseshell butterfly looking somewhat tatterdemalion after emerging from hibernation, warming up in the early morning sunshine on an old farm machine

Holly blue butterfly

I haven’t seen many interesting moths yet this year, but late one evening last week, whilst quietly watching TV, this beauty emerged from behind the sofa, to the general consternatiion of all in the room, fluttered around very rapidly for several seconds before homing in on a lamp and alighting inside the shade:


Emperor moth female inside a lampshade

As you can imagine, her choice of resting place gave an additional challenge to the photography but I like this picture. The male is even more colourful with orange hindwings and believe it or not the emperor moth, Saturnia pavonia, is native to the UK, not an import from the rainforests! Emperor moths are big with a wingspan over 7cm, and they live on moors and in open countryside where they feed on brambles. The males are out and about in daytime looking for mates in April and May and the females are abroad at night, I guesss looking for safe places to lay eggs. It is the UK’s only resident member of the Saturnidae family.

Wandering warblers

In the last two to three weeks I’ve seen several of our migrant bird species which have been returning from Africa and Eastern Europe for the breeding season in the UK. And in the sunny weather we’re experiencing this month lots of bird species, migrant and resident, can be seen during an early morning walk.

Last Sunday the weather was glorious, there was very little wind so there was no traffic noise so the only sound in the air was the buzzing of insects and the singing of birds. And there were plenty.

I set off with my friend from work, Dave, who is very knowledgeable about wildlife and a very good photographer too (check out his website here for some stunning images). Dave had come over so I could show him the local Histon wildlife and it didn’t disappoint. Within a couple of hundred metres of leaving my house we were watching a group of five blackcap chasing each other through the trees.


Male blackcap perched in an ash tree

Male blackcap are very aptly named, they have a very prominent black cap which stops just above the eye, the female and juveniles less so, theirs are a lovely rufous brown colour and also very distinctive. The blackcap is a short distance migrant in western and southern Europe and I’ve heard that there is now a population in eastern Europe which migrates to Western Europe and the UK instead of heading south. Maybe that’s down to global warming causing increased spring temperatures here.

Other migrants which we saw in good numbers, and which I’ve seen around north Cambridge for the last three weeks or so, are chiffchaff, willow warbler and whitethroat. The chiffchaff heads south to the Mediterranean for winter and some individuals carry on to sub-Saharan Africa.

The willow warbler heads further south to tropical sub-Saharan Africa for the winter:


Willow warbler sitting in the top of a hawthorn tree

Chiffchaff and willow warbler are very difficult to tell apart visually, but they can easily be distinguished by their song. The chiffchaff is named after it’s call which is a single note sung with alternating pitch, the willow warblers song is more musical and easily distinguished from the chiffchaff.

Whitethroat of which there are two species – common and lesser – over-winter in sub-Saharan and northeast Africa respectively.

Common whitethroat male singing from his perch on a bramble

It’s good to see the migrants returning from Africa, I don’t know what percentage of individuals that start what must be an extremely hazardous journey make it back to the UK, but the willow warbler in particular is a very common bird so good numbers must make it.

The other migrant which I’ve seen in the last week, which is the real harbinger of summer, is the swallow. I only saw a single one first time on the 16th April, which was busy hoovering up flies over a field of oil seed rape, but yesterday I counted 7 sightings over the same field, so I think the numbers are increasing. And since then we’ve had real summer weather!

April in bloom

A walk along a hedgerow can be a particulalry rewarding experience just now. The trees are all in leaf and horse chestnut (Aesculus hippocastanum) trees are in bloom and hawthorn (Crataegus monogyna) is puntuating the hedgerows with gorgeous stretches of white flowers,


Willow warbler (Phylloscopus trochilus) beautifully fremed by hawthorn blossom on a sunny day in April

Wildflowers are also in bloom, and lining my walk routes this month are  cowslips (Primula veris):

…and white deadnettle (Lamium album)

The cowslip, a member of the Primula family which includes primrose and oxlip, are not as common as they used to be but occasionally a roadside verge or a bank or edge of a ditch will be swathed in yellow from their flowers. The cowslip could be confused with the similar oxlip but the flowers of the oxlip are more pale and more open, like those of a primrose. Until recent times it was used  to make wine and the garlands on Maypoles, and has been used medicinally to treat headaches, whooping cough and as a diuretic and expectorant.

Conversely, white deadnettle is much more common and can be found lining field edges, road verges and hedgerows. It flowers from March to December and the nectar is at the back of the flower so can only be fed on by larger insects such as bumble bees which can open up the flower to get to the nectar. It is known as a ‘deadnettle’ because its leaves resemble the stinging nettle but it can’t sting because it doesn’t have the stinging hairs. It is easily distinguished from the stinger by its flowers which are white or pink compared to the stinging nettle flowers which are small and green. It has historically been used in herbal remedies for catarrh and the young leaves and flowers can be eaten as a vegetable.

Many other flowers are blooming now such as the common-or-garden buttercup (Ranunclus acris), daisy (Bellis perennis) and dandelion (Taraxacum offficinale):


Dandelion flower, named from the French for ‘lions tooth’ – Dent de lion

Dandelion flowers heads are made up of many smaller florets and are open in the daytime but close up at night. The leaves have been used in salads in many countries either raw or blanched in boiling water to remove any bitter flavour, and the roots can be roasted and ground into a coffee-type drink. It has been used as a traditional remedy for urinary tract infections and as a diuretic.


A dandelion seedhead – a masterpice of natural architecture!

Cow parsley mallow and other wild flowers will all b e in full bloom on the near future and the flies and butterflies that depend on them will also be out and about.

Guns Lane bird walk 2nd April 2011

I acquired a voice recorder last week. It’s tiny – not much bigger than a  cigarette lighter – and it means I can record what I see alot more accurately as I don’t need to rely on memory. Which is a good thing as my memory is not brilliant. The weather was glorious on Saturday and Sunday morning so the timing of my acquisition was pretty good because there was an awful lot to record when I was out and about.  The birds are very busy right now building nests and in the last couple of weeks blackbirds have been collecting strands of hay ejected from the rabbit hutch in my garden and I’ve seen various other species with beaks full of grass, twigs and moss.

Apart from enjoying the sunshine I saw two species of bird for the first time this year – blackcap and linnet. A pair of linnet appeared to be in residence in a bramble at the southeastern end of Rowleys Meadow, Histon. (On the map, Rowleys Meadow is the area of green scrub in the middle.)

Linnet perched on top of a bramble

The blackcap were in the northwestern hedge row at the opposite end of the field to the linnet and perched, tantalisingly, directly over my head, so my photographs are all of the underside. I saw one pair together and two individuals on this walk which is almost as many as I’ve seen in Histon in total in the last three years.

Also in the same hedge along the northwest periphery were several yellowhammer and in the bright sunshine the colours were amazing:


Yellowhammer male sitting atop a branch beautifully lit by the early morning sun

Yellowhammer are a species of bunting that are resident in the UK so can be seen all year round and breed here. They feed predominantly on seeds but also on insects which they harvest from the ground. I often see them perched on top of hedgerows and they fly to the ground when flushed where, despite their colour, are often next to impossible to see. The female has similar markings to the male but  is much less yellow.

Pair of yellowhammer, male  on the left and female to the right – I was very pleased to get this picture as they’re normally so difficult to see on the ground

Yellowhammer are currently on the red list due to the decline in numbers over recent years, although there seem to be good numbers in my locality and I’ve even had one feeding in my garden!

Many species of birds were busy this weekend, including a buzzard, a pair of sparrowhawk wheeling around way up high, and a pair of kestrel. Closer to the ground, blacdbird, chaffinch, greenfinch, long tailed tit and songthrush were all very much in evidence.


The unmistakably speckled underside of a songthrush

Butterflies are also starting to emerge in the warm weather and a couple of red admirals and two others which I couldn’t see close enough to identify were floating along the brambles.

A good photograaph of a blackcap eluded me this weekend as I only managed to shoot it from directly underneath so the cap wasn’t visible, but I shall have another look this weekend and hopefully post a ;picture next time.

Toad migration

It’s the time of year when our resident amphibians are mating and heading for the nearest stretch of water to spawn. I find it a particularly stressful phenomenon due to the number of frogs and toads that need to cross roads and don’t make it. In my vicinity the completion of the guided busway running into the north of Cambridge has imposed an impassable barrier to thousands of common toads, Bufo bufo, which hibernate in the woods and hedgerows along the northern edge of the busway.


Pair of toads, the lady is the larger one underneath doing the legwork

It’s clear from the picture that the toads stand little or no chance of negotiating the sheer walls at the side of the busway – and even if they did they would have a further three to climb on the way to the lake and all four again on the way back. All this whilst numerous pedestrians and cyclists are making their way to school in Histon and work on Cambridge Science Park. It’s an extremely hazardous operation.


A pair that made it on their way to the water

When they make it to the water toads lay strings of eggs, as opposed to the gelatinous mass of eggs laid by frogs, and their tadpoles are slightly shorter and fatter than frogs. They feed on vegetable matter and absorb oxygen through their skin. As they grow they develop lungs and come to the surface to breathe. Eventually the tadpoles metamorphose into adult toads and the tail shrinks away at which point they leave the water as immature adults and will only return to the water to breed.

Adult toads differ from frogs in that they don’t hop, they walk. The colour of toads is also rather different, they have light ot dark brown warty skin with darker spots and frogs have more homogeneous green and smooth skin. And the eye colours of the toad is gorgeous – a lovely deep reddish gold. I like toads, they eat garden pests including slugs and are consequently good things to have around.

As with alot of creatures with the word ‘common‘ in their name, this is something of a misnomer, because of habitat destruction and the best attempts of predators including domestic cats they are no longer common. They secrete a toxic irritant through the skin but some predators are immune to this so they still get eaten.

It’s a real struggle being an amphibian in modern Britain so if you see one heading for the water – or on the return trip – please rescue it and help it on its way by placing it out of the way of humans, cars, cats etc.

Norsey Wood

Last weekend my wanderings took me to Norsey Wood on the  eastern edge of Billericay in Essex. The weather was sunny and warm so a stroll through this chunk of ancient woodland was compulsory. The wood is a lovely place and has a history dating back 4000 years. It is now a mixed coppice bluebell wood and in a month or so the floor will be completely blue. At the moment, the bluebell leaves are sprouting but no flowers are out but there are wood anemones (Anemone nemorosa):

Wood anemone flowers pointing at the sun

And lesser celandines (Ranunculus ficaria):

Wood anemones are interesting plants. They’re toxic and contain chemicals which have been used medicinally but which can cause some pretty unpleasant effects if ingested such as vomiting, diarrhoea and gastric bleeding. Best avoided. Despite that, a wood floor covered in them is a wonderful sight to behold. Lesser celandine are rather lovely too, with similarly interesting properties. According to its Wikipedia entry it has warty nodules which resemble haemarrhoids, so ancient law dictated it must therefore possess anti-haemorrhoidal properties. Bizarre logic, but you never know, maybe there was a grain of truth in it. It doesn’t mention how the active ingredient was applied though!

I saw a group of four jays squabbling in a tree but the woods were generally fairly quiet for birds on that day. The animal which was present in enormous abundance was the woodant, Formica rufa,


Wood ant worker – these are around 1cm long

The workers are all female and if attacked they have a ferocious bite and can spray formic acid from the rear of the abdomen. A loner wouldn’t trouble a human but disturbing a nest which may contain several hundred thousand would be ill advised.


Thousands of woodants all busy around the entrance to the nest

They’re amazing creatures and build nests from plant material such as leaves and pine needles which can be a metre deep. As they act as an incubator and creche the temperature has to be very carefully controlled which is achieved by opening and closing vents to regulate airflow through the nest. So they’re fearsome warriors, highly competent parents and civil engineers too.

The organisation and division of labour amongst woodants is also remarkable. They have territories covering large areas and I’ve tracked them from a nest to a foraging site and the distance is many tens if not hundreds of meters which they negotiate in straight lines where possible and will clear away any debris which  blocks the way. Amazing creatures.

I’m hoping to make a trip to Norsey Wood in May when the bluebells are in bloom so I’ll hopefully post from there again later in the year.