Knock on Wood

Magical late afternoon walk across Burwell Fen.  Waders in abundance, often showing well and in great light.  At one point I counted 14 Wood Sandpipers and there were likely to have been more, 6 Green Sandpiper were outnumbered as was the lone, bobbing, Common Sandpiper.  A Spotted Redshank picked through the vegetation and 4 Whimbrel flew over agitating a rather panicky seven whistles as they travelled South.

 There were lots of Ringed Plover picking over the mud and Dunlin joined their feeding troop.  a smart juvenile Little Stint joined them and a party of Black Tailed Godwit flew over. 

Having filled my boots on waders I decided to look at the Lazy Otter floods to see if any gulls were visiting.  It turns out that they are not and the high water level, maintained through pumping, is not leaving much mud for waders either.  However 2 Wood Sands, a Ruff and a Dunlin squeezed themselves onto a metre of mud on the peninsular. 

As the sun dropped an pinked the sky, there was movement on the Old West River as a pair of Great Crested Grebes were feeding young, I guess from a second brood, and one was still catching a ride on it's parents back.

 

Fade Away

For one reason or another my time out in the Fen has been pretty limited this summer, I have been exceptionally fortunate in having the odd half hour here and there in different parts of the country to enjoy a smidgen of Purple Emperor , a smatter of Silver-spotted Skipper and an adulation of Adonis Blue.  I revelled in a protracted tussle between a Peregrine and a Goshawk across an indigo of heather and regiment of pine.  A lone Skua harried a Kittiwake as a 2 CY Med Gull looked on from the beach, non-plussed to know it had an age....

So within a tepid revelry, of sorts, I took another gifted hour in the wild at Welney where almost all was in slumber.   Ruff in an abandonment of definition gifted variety and over a hundred, far more than your average can of Heinz, picked around the slowly wetting lagoon.  The odd bird harked back with heckles raised to a time, on the tundra perhaps, where valour was all and all was to play for.

 

A similar aesthetic reduction has occurred to the Garganey, honourable raspberry blower of the Fen.  Long gone are the cascading pied and spring skied scapulars and the white browed on chocolate promise of May but here the rewards. Two of this years young with seemingly non-plussed parents, who still spring from the mire and flank the young when a harrier coasts by, mingle with the other moulting duck and dabble occasionally within the algae rich soup of the pool.

 

 

Another BBC NHU video beckons...but then again how is anyone going to drag you away from the Big Blue on TV....if you've not spent time on the sea off Monterey then, if you can, just go. 

 



 





Another Gull, Another Planet

There are a few flooded fields around the Chittering/Dimmock's Cote area at varying levels of saturation.  The tastiest looking flood is viewable from the riverside walk near the Lazy Otter Pub adjacent to the A10, wader wise it is starting to gather some momentum with 28 Ruff, 7 Dunlin (inc 1 fresh juv), 4 Green Sandpiper, Greenshank, 2 Ringed Plover and a Little Ringed Plover yesterday evening.  I didn't see the Wood Sandpiper of the past few days and I was also far too late to enjoy the previous evenings  moulting Black Tern.  What I did see was the makings of a Gull roost that unsurprisingly, given our location and the late summer build up of numbers, contained a reasonable proportion of Yellow-legged Gulls.  Below are some of the birds present amidst the Lesser-black Backs, always offering some level of challenge I have labelled these with what I think is within the gulls, you may not agree. 

With the lure of migrating waders and wetland birds and the chance to pick through Gulls too I shall be heading back here with some frequency as, I guess, will many others as it's probably the best bit of wader habitat in Cambs at the moment.

1 x ad YL Gull



1x 2CY and  1x 1CY YL Gull here I think

 

1x 1CY YL Gull

I'd rather be a Sparrow than a Snail....

The House Sparrows seem to be doing OK around Stuntney Heights and in addition to the 40 or so post breeding birds frequenting a nearby stretch of hedge we have 3 pairs preparing, or more accurately renovating, their nests beneath our eaves for a second round of breeding.  This has given me plenty of opportunity to say a cheery hello back to their chirruping and admire them in their varying states of  smart brownness.

More Crossbill Traffic

Four Crossbills flew North over the Village College in Soham, chipping away yesterday morning and 2 Siskins were vocally flying back t'other way.  A Kestrel had an accident and flew headlong into the window of a parked car and spent the rest of the day, forlorn and confused, stood on a beech stump on the lawn in front of the old school.  We checked that it was not in too bad shape and it didn't appear to have broken a wing so hopefully it made a recovery and not become Fox fodder, as it was not to be seen this morning.

Syncopated Chiffchaff

During the fantastic Ely Wildspace Bioblitz last weekend this Chiffchaff singing along Kiln Lane during the Saturday morning Dawn(ish) Chorus walk drew attention to itself.  Initially I thought it was two birds singing but I was able to confirm, from observation, that it is the song of just one bird.  The syncopation of the song is unusual, earlier in the season the exact same song posts were used by a standard singing bird, is it the same bird with a variation over time??

Return of the Whiff-whaff

For the third year in a row there is a Whiff-whaff - a bird singing a mixture of Willow Warbler (WILWA) and Chiffchaff (CHIFF) song - on St Edmund’s Fen at Wicken.  This bird seems to have gone unnoticed by the bold Fen ringers so we have no record of how it started out.  I first heard on 23-6-15, quite late in the season, but it was still singing heartily, switching readily between Willow Warbler and Chiffchaff, but usually giving at least a hint of the other in each song.

 

 

 

The first time I heard one at Wicken was when I was conducting a survey on St Edmund’s Fen back in 2013.  I marked it down as a Chiffchaff but kept a mental tag on it so as not to double count.  Suddenly it’s Chiffchaff-ing gave way to the liquid cascade of a Willow Warbler.  I followed that bird through the summer and gradually it introduced more Willow Warbler song, but still keeping plenty of Chiffchaff in its repertoire.  I captured a Willow Warbler in its territory and fitted it with a metal ring coloured red with a permanent marker pen.  After some hours mapping out its singing circuit I managed to see the bird and its red ring while it delivered a mixed song.  By an even greater stroke of luck I also stumbled upon its nest, which Carl Barrymore confirmed was of a Willow Warbler’s construction: this bird was a Willow Warbler and furthermore had been able to attract a mate despite its odd song.  Later that year it broadened its repertoire still further with tit-like phrases unlike either Willow Warbler or Chiffchaff.  Sadly, the nest was later predated.

 

    

 

The first Wicken Whiff-whaff

 

I picked up the second bird in May 2014.  Initially it sang plenty of standard Willow Warbler plus either chiff-chaff followed by a Willow Warbler’s cascade or a typical Willow Warbler finishing with a couple of chiff-chaff notes.  But again the song tended to become more elaborate starting with a crescendo-ing wee-wee-wee and ending with some chiff-chaffs.  I also recorded some repeated see-see-see notes (followed by chiff-chaffing) that were so far from a Phylloscopus that I can’t be sure it was coming from the same bird at all.  This bird did NOT wear a ring.

This year’s bird was, by comparison, quite conventional, as you can hear from the attached recordings.  In the first the bird is singing quite Willow Warbler-like with Chiffchaff inserts from the top of a birch tree; in the second, recorded a couple of minutes later, after the bird had dived into a willow thicket (bees and flies and leave rustle giving a lot of hiss) it proceeded to sing like a Chiffchaff, often after a very brief aborted snatch of WILWA song.  I can’t be certain whether this bird had a ring, but probably not.

 

There have been plenty of others: I recorded another in Witcham last year and almost everyone I speak to seems to have heard one.  Ben Green has even reported on from Ely this year.  It seems that this “mixed singing” has been noted for over 100 years.  British Birds had an article about it in 1940, there are notes on the phenomenon in BWP (vol 6, p657) and Gwentbirding blog wrote about it at length in April 2011.  It also appears that it is much more common and widespread than is generally realised. Those that have been identified with certainty have almost always turned out to be Willow Warblers.  At this point, when it is clear that this in not something exotic, too many birders lose interest.  But quirky phenomena such as this are of more than passing interest: anomalies can be useful in testing hypotheses.

So what is going on here?   Some common themes that emerge from the records:

(i) the Chiffchaff-like elements of their songs are usually delivered more rapidly and at a slightly higher pitch than a Chiffchaff;

(ii) the bird often starts with a predominantly Chiffchaff-like song but elaborate with much more Willow Warbler as the season progresses.  But is this progression an artifact of the fact that the mixed singing is what draws attention to the bird in the first place?  The Willow Warbler elements of its song may become more apparent later as the bird is followed.

    

It is unlikely that the Wicken birds were the same individual but perhaps they were related, raising the intriguing possibility that this type of singing is genetically inherited.  (Alternatively, sons may have learnt their aberrant song from their father.)  They may be imitating Chiffchaffs, though it is hard to explain why they all do it at too rapid a tempo and too high a pitch. All Willow Warblers do deliberately vary their song, one individual hardly repeating the same version twice.  (No two Chiffchaffs sing exactly the same song either.) It does appear that these “mixed singers” also vary their song more than most.  Whether that is because they are dunces who are not sure what they should sound like or superstars with a particularly varied repertoire is hard to tell.

     Contending theories include the following:

1. It’s neither a Chiffchaff nor a Willow Warbler

a)    Phylloscopus trochilus x collybita hybrid.

b)   Vagrant species.
[Hybrids and vagrants (P. tristis and P. ibericus) certainly occur but do not usually sound like Whiff-whaffs.]

2. Song mimicry, mixing or switching

a)    It’s learned the wrong song.
[If imprinted on the wrong species why do birds become worse at reproducing their model song as time passes?]

b)   It incorporates song elements from another species in order to augment its own song.
[If the purpose is ornamentation why do these birds, at least initially, often deliver such a simple chiff-chaffing song?]

c)    It copies song of another species in response to competition from that species.
[If singing is about real estate rather than sex, why doesn’t the female sing too? And why does the song become more WILWA-like as the season progresses, when mating is over and inter-specific competition relatively more important.]

3. No mimicry involved

a)    Unusual variant of normal song.
[While typical WILWA song is surprisingly varied, and often begins with a number of repeated syllables, rarely do they alternate two notes.]

b)   Primitive song produced by immature bird, perhaps one that has never heard a male Willow Warbler sing.
[Perhaps WILWA and CHIFF start with a similar primitive innate song that normally the WILWA elaborates in a process that fails or is retarded in Whiff-whaffs.]

 We need more observations to provide further clues.  I would be very interested to know if anyone else hears one, or has heard one recently.

Coturnix from slumber

Lights out last night and head to the pillow having read the introduction of whimsical lepidopterist Matthew Oates's In Pursuit of Butterflies.  I hadn't even started dreaming of iris and camilla, the Emperor and the Admiral, when the tri-syllabic whip of a Quail drifted through the open window from the field in front of the house.  This continued for some 5 minutes and I did fling the window wide to get a good earful of this summer treat. Whether he continued through the night I'm not sure but I'd love to have the pleasure of being lulled to sleep by Quail throughout the summer.

At the back of the house the Turtle Dove has become vocal again and doing some lovely display flights.  I presume this is in preparation for a second brood although I haven't seen any evidence that the first was successful as yet.

Piping hot

The Summer overlap has begun. Just as the weather has finally warmed up, and with migrants still arriving from further south, the first northern travelers are beginning to pass back through after their brief sojourn at the higher latitudes. The pool in front of the main observatory at Welney has shrunk, exposing a wide tract of mud on which the waders are feeding. Among the Lapwings and Avocets, a beautiful male Ruff probed along the shore, still wearing his ruff like a well worn Bedouin head scarf. Closer to me a collection of sandpipers fed and preened , and provided a perfect illustration of the similarities of three species.

The largest of the three is the redshank, and thanks to a very successful season there were plenty of fresh young birds, neatly fringed with green-gold, with legs that have not yet bloomed to full scarlet. 

Looking very similar, though much  smaller, a dainty Wood Sandpiper has returned from the breeding grounds in Scandinavia (or possibly Scotland even), a slender bird with spangled breeding plumage still evident. It's strong supercilium gives a slightly intense look to it as it pokes at the surface for small flies.

Two green sandpipers loafed on the muddy shore, before venturing out onto the water to feed. superficially like the Wood Sand, the Green lacks the obvious supercilium, and its spangling is not as bold. The dark underwings and broad tail bars are a real giveaway.

Summer terns up

I got a call from Bill this afternoon about the terns at Roswell Pits. He wanted to know exactly how many chicks there were, and I told him I thought I could see three on Friday, when I was leading a bunch of excitable school kids around the site, (and therefore not having my telescope to hand). 

Just to make sure, I thought I'd wander up and confirm this, and have a good look at them as well. At first I could only see two, but as the parents arrived with food, the third shuttled into view to join its screeking siblings. Their subtle plumage of powder grey and white, burnished on top with bronze and black-cap, was contrast to their raucous begging at the approach of fish, though there was not much squabbling between them. They're obviously well fed, and on this warm day they spent much of the time dozing, bills drooping on their chins.

Closer to me, a lone grebe bobbed gently on the sparkling water, preening as it turned in circles.

Near the bridge, three Chiffchaffs relentlessly sang , every few notes interspersed with a mid-summer stutter, and in the heat of the afternoon they perched high up- blending in with the Ash leaves, and not scuttling about as they do in Spring. Summer has finally settled, it seems, and only one short gust of wind arrived- a pleasant change as today the breeze was a salve rather than the bothersome interference of recent weeks. Down at the settling beds the dry song of Reed Warblers could be heard above the slight rustle of Phragmites, and three well grown Pochard ducklings dived constantly- emerging with silt-caked faces.

Venetian blinder

It seems as if the trees have been shivering in the cool breeze since the Spring, and the wind has been blowing summer through the fens too quickly for my liking. Yesterday, however was one of those rare still days of blue sky and warm air. The raptors were up over the garden- a Marsh harrier glided past and a Hobby stooped and was lost beyond the tall hedge, only to swing back up and away down the village. 

We decided to wander down to the pits so to better take in the skyscape, and it wasn't long before more harriers flew into view. It looks like one of the nests is about to erupt, as a female brought in a vole and circled above, tempting the young birds into the air. The nestlings refused to show themselves, but, as another female arrived, two fresh harriers took to the air to claim the food. One of them was a normal juvenile, with rich sepia wings and sienna cap, but the other looked like nothing I have seen before. 

Over the years I have seen hundreds of Marsh Harriers, and it is their variation that attracts me to them, making individuals often very distinctive. Following a basic design, it can seem that the infinite variety of plumage combinations can give each bird a unique look, with wing patches large or small, underwing colours pale or dark, streaking and speckling- even eye colour differs between them. I did think that I had come across all the likely types to be seen, from dark males to pale females- but the second juvenile seen yesterday sported a uniform that dazzled. Although not up in the air for long, and quite distant, we could make out striking white tips to the wing feathers and mantle that completely transformed the bird into something special. Unfortunately I didn't have my camera to hand, so I've done a quick sketch back at home to try and capture the image. If this bird turns up anywhere in the country this autumn it will be easily recognisable, and it may well give us an opportunity to study the dispersion habits of these wandering hunters.  

Please place the sea before precipitation

Plans for a solstice seek out of butterflies on the Suffolk coast seemed futile with poor ground temperature and very little sun peeking through the cloud cover.  In recompense I was treated to an lunch at Welney and an afternoon potter across the bridge onto the reserve.  The undoubted highlight was this trio which included a colour rung bird from the Great Crane Project.  There was a Quail doing some sporadic wet lipping and a male Peregrine whipped through and nabbed a chick of some description on Lady Fen.

 

 

I also got quite transfixed with the progress of this Leaf Weevil as it made it way along the handrail into one of the hides. 

The reserve staff and volunteers are lovely at Welney and we were over the moon when our little one was asked to help with the moth release prior to closing up.  She particularly liked the Elephant Hawkmoths as they are pink and matched the flowers on her dress.

I was particularly happy to see the Eyed Hawkmoth which I'm still to attract to my garden MV trap.  It only flashed it's underwing briefly but although blurry you can see why any predator would consider this moth to be a great deal bigger and more foxily ferocious than it ever could be, a great bit of evolution.



 

The sun hadn't poked out enough to warrant a second check of Chettisham Meadows for Marbled Whites so we had a good look at the Bee Orchids off Norfolk Road, Ely.  They're great plants and I tried a few different things to try and present them a bit differently.

Someone I met recently declared that the increased interest in Butterflies, Moths, Dragonflies and the like is down to what he called bored birder syndrome.  I think that's a bit disingenuous, there's just so much stuff growing and crawling and flying around over the summer, the very last thing any kind of naturalist can be at this time of year is bored.  Do bored botanists start looking at birds when the snow falls ??



Crossbill Traffic

It's been some years since I've seen or heard a chipper chupper in the Ely10.  On Tuesday me and 25 thirteen year olds were out on the school fields of Soham establishing whether we could measure the  speed of sound (of course we could but not very accurately they discovered).  The distinctive chip of a Crossbill overhead was a pleasant diversion and it flew over low enough to establish that it was a female type.  6 or 7 years ago there was a spell in July and August when I was recording flyover Crossbills most weeks, let's hope that there are a few more before the summer is over.

Phalarope

I didn't manage to get back to Welney, but I worked up a watercolour of the Phalarope from sketches done on Saturday. This last few days have thrown up some very big birds all over the country, but sometimes the littlest can be worth a look too. 

Bee is for orchid

Nature has a way of turning up where you least expect it. On the north western limits of Ely, just inside the enveloping A10, a stretch of grassland to rival that on any local nature reserve is alive with incredible lilac bees, clutching fresh green stems in groups of four or five, quiet in the cool evening shade. The meadow patches are nestled among small stands of low bushes and young trees, and Blackcaps and Wrens sing an evensong. One voice stands out for it's strangeness. It starts with a couple of chiff-chaff notes before descending into the stream of Willow Warbler. I glimpse the singer briefly- just it's head, and its bold supercilium and pale cheeks show that this bird has learned a new introduction to its verse. I can't help feeling that the lack of other Willow Warblers in the area this season have led this lone warbler to adapt like a backpacker studiously picking up useful phrases of the local language.