Category: Biology

The pectoral sandpiper (Calidris melanotos) is a migratory wading bird that breeds in North America and Asia, winters in South America and the South Pacific, but also spends time in Siberia. However, you can see them in the UK and Europe. They’re often caught on Westerly winds and hit the British Isles from North America and on Easterlies that bring them in from Siberia.

Most commonly, they’ll be seen in late summer and autumn. There were quite a few on the wetlands at RSPB Titchwell in North Norfolk when we visited in mid-July. According to the RSPB, “It is the most common North American wading bird to occur here and has even started to breed in Scotland very recently.”

The sandpiper name refers to its call and to its shoreline existence while the pectoral refers to the bird’s brown breast band. The scientific binomial is from ancient Greek: kalidris or skalidris was a term used by Aristotle to refer to some grey-coloured waterside birds while melanotos is from melas meaning black and notos meaning backed.

Originally, in this post, I’d displayed a photo I took of what I assumed was the Pec Sand, but on later inspection turned out to be a Ruff, so I’ve removed the photo.

Eurasian magpies (Pica pica) obviously have a special place in the heart of any Geordie, their black and white plumage with a hint of blue being the football strip colours of Newcastle United, obviously.

The birds’ reputation as thieving magpies is misplaced, although like most corvids (crows), the bird is attracted to objects such as coins and buttons which it might use to decorate its nest or simply collect because they imagine such objects are seeds.

As I think I’ve mentioned before, corvid cognition is much higher than one might anticipate based on brain structure of these descendents of the dinosaurs. Crows seem to be far more intelligent than our understanding of the brain based on mammalian biology (think clever rats and monkeys) suggests. The same also applies to parrots and related species and perhaps all birds.

These photos were snapped of a juvenile on one of the jetties overlooking an old gravel pit pond at Milton Country Park north of Cambridge. The bird was stood on the fence and started doing his song and dance routine when he saw us and the dog. It was a bright, but fairly grey day and his bright white and deep black means getting light readings and setting bracketing for a decent shot before he flew off was next to impossible. I quickly fired off as he squealed and flapped and then nudged the levels in the photos to get the most dramatic tones.

Incidentally, my reference to them being shy is that usually adults out in the countryside will take to the air and head for the middle distance or the nearest trees almost as soon as they see you, which is often before you see them. This youngster was in a relatively busy area and maybe hadn’t yet learned to recognise the risk of dogs and humans.

UPDATE: There are several accessible chunks to this reserve now in addition to the Needingworth side: The Over side, which is the shortest route to the Reedbed Trail via a very rough drove, parking is potholed, but the section is beautiful, the Earith entrance which is relatively new, good parking. Also, you can access the Barleycroft Lake section from another reserve RSPB Berry Fen. At some point, these will all be joined by trails so you should be able to park in Earith and wend your way through to the Reedbed Trail, across the Great River Ouse and through the Needingworth side.

I am bit reluctant to tell you about the little jewel I have found. It’s not three quarters of an hour’s drive from Cambridge. Although the title of this blog post sort of gives it away…

It’s a lovely picturesque place, lots of decent footpaths, trees, ponds, hedgerows, reed beds, and lakes, and lots of bird life. And, there was nobody else there almost the whole time I wandered around, I only saw one couple when I arrived and a couple of people as I was leaving.

Admittedly, it’s a former gravel works/quarry and is flanked by active quarrying, which is feeding materials to the A14 roadworks, I reckon. The site will no doubt be rendered as a nature reserve when they have scooped out the last of the shingle and sand. Of course, many a nature reserve emerges from quarried land, better than it being used as a landfill site.

Anyway, we had hail this morning, thunder and lightning, and torrential rain. My plans to visit were almost scuppered, but the clouds cleared a little and I jumped in the car, camera in hand. By the time I got there the clouds had regrouped and it was spitting with rain, half a mile into the reserve and there was thunder and no little lightning. I was too far away from the Faraday cage of my car, so I clung to the hedgerows and kept camera dry in my coat until the storm passed and the clouds broke again. By mid-afternoon it was too hot and I had no water.

So..the birdlife, lots of green woodpeckers (Picus viridis), juvenile pictured above. They’re also known as yaffles around here and generally feed on ants along the footpaths and on the clear spaces, there were common terns winging it over the lakes, moorhens, swans and numerous reed warblers (Acrocephalus scirpaceus) in the, you guessed it…reeds (top photo). I inadvertently scared a buzzard (Buteo buteo) from its woodland perch into flight, I turned out of that wooded area and caught sight of a red kite (Milvus milvus) pictured below. You’ll notice both of those latter scientific binomials are tautonyms, that means they repeat the first part of the name and it implies that this species is the “type” of the family, the achetypal species one might say.

I heard at least a couple of turtle doves (Streptopelia turtur) in the undergrowth of another wooded area, but didn’t see them. Saw one or two reed buntings (Emberiza schoeniclus), but heard many more. Rare was the sound of chiffchaff (Phylloscopus collybita), until after three hours of walking I’d got back to the car. I don’t think I heard nor caught sight of a willow warbler (Phylloscopus trochilus) at all.

In abundance, however, were goldfinches (Carduelis carduelis), another tautonymic bird, whitethroats, blackbirds, starlings, long-tailed tits, great tits, blue tits (all three species with juveniles in tow), wood pigeons, wrens, lapwings, yellowhammers, dunnocks, common tern (below) and a few unidentified LBJ (little brown jobs). There were even oystercatchers around.

More intriguing though were the warbler-type birds at the farthest point away from the (free) car park. I certainly saw a few more reed warblers, perhaps a sedge warbler, in this area of the reserve (the reedbed trail). But, looking at the shots I got I cannot positively identify some of them as they were flitting among bushes and out of sight. Others, it turns out, are whitethroats (Sylvia communis). The barbed shot below is a juvenile, Mrs Sciencebase suggests.

Now, I’ve told you about the place, I would recommend a visit if you enjoy the peace and quiet of a nature reserve, although there is a bit of industrial traffic and the endless churning of the gravel conveyor belt for the quarry, but don’t let that put you off. Looking at the RSPB map for the site, I see now, that in my three hours, I only saw half the site, so another visit is needed…might even get a shot of an adult yaffle!

Over the last few months I’ve got to learn a little about the birds we call warblers. It was always a joke between Mrs Sciencebase and myself, if we heard a tweet we didn’t recognise one of us would proclaim “warbler!” and we’d move on…

Well, it turns out that a lot of the time we were right without knowing it. I’ve snapped a few of them and we’ve definitely heard the grasshopper warbler (at RSPB Folwmere) but don’t think we’ve seen it.

Cetti’s warbler – WWT Welney

Sedge warbler – RSPB North Warren, Fen Drayton Lakes, Ouse Washes

Reed warbler – RSPB Fen Drayton, Ouse Washes

Common whitethroat – RSPB Bempton Cliffs, South Cambs

Lesser whitethroat – Rampton, S Cambs

Blackcap – RSPB Minsmere, Rampton, Cottenham, elsewhere

Willow warbler – Rampton, Cottenham, elsewhere

Chiffchaff – See and hear almost everywhere there are trees

Grasshopper warbler – possibly heard at RSPB Fowlmere and Overhall Grove

Marsh warbler – yet to positively ID, very rare, 2-3 breeding pairs in UK

Wood warbler – Photographed in Croatia

Dartford warbler – Seen but not photographed at RSPB Minsmere

Moustached warbler- yet to positively ID

Sardinian warbler – ditto

Savi’s warbler – ditto

Sub-alpine warbler – ditto

Bonelli’s warbler – ditto

Great reed warbler – ditto

Garden warbler – ditto

Pallas’s warbler – ditto

Yellow-browed warbler – ditto

Icterine warbler – ditto

Melodious warbler – ditto

Barred warbler – ditto

Fan-tailed warbler – ditto

 

The term warbler applies to some distinct species as you can see, it’s more of an umbrella term for perching (passerine) birds that share characteristics, such as being fairly small, vocal, and insectivorous.

The shape of a bird’s eggs depends on how it flies, according to new scientific results. Sleek birds adapted to streamlined flight tend to lay more elliptical and asymmetric eggs, according to new research published today. The work cuckolds the classic theories about egg shape.

Broadly speaking, birds’ eggs can be ball shaped or elongated ovals. They can have one pointy end or be very symmetrical. Diet, nest space, cliff dwelling and other factors have all been scrambled to explain why some eggs are one shape and others another. Now, Joseph Tobias from Imperial College London, writing in the journal Science explains how he and his colleagues have measured the shapes of almost 50,000 eggs of 1,400 bird species. They analysed this hard-boiled data in the context of the bird family tree and species characteristics, such as nest type, clutch size, diet, and flight ability.

The researchers discovered there was a correlation between strong fliers and more elliptical and asymmetric eggs

The team found that murres, aka guillemots, (pictured above, prepping some eggs) which are fast, direct flyers that can also dive deep underwater had some of the most asymmetric eggs in the study. This was previously thought to be about precluding the egg rolling off a cliff edge into the sea below; an over easy theory. By contrast, owls – built for light, gliding flight – had some of the most spherical eggs, although the barn owls eggs are rarely sunny side up as it’s a dusk/night hunter.

“Bird eggs – previously described as ‘a miracle of packaging’ and ‘the most perfect thing in the universe’ – have fascinated people for millennia, yet only now are biologists beginning to crack the mystery of what makes some eggs more ‘egg-shaped’ than others,” says Tobias.

Lead author on the paper Mary Caswell Stoddard of Princeton University, adds: “In contrast to classic hypotheses, we discovered that flight may influence egg shape. Birds that are good fliers tend to lay asymmetric or elliptical eggs.”

The most obvious reason for this adaptation is simply that the sleeker fliers have less room in their abdomens and narrower oviducts for spheroidal  eggs. So, it’s a packaging problem for mother birds.

There’s no poaching of theories here, Tobias says that his team “found no support for the traditional ideas that variation in egg shape is caused by nest structure or placement on perilous cliff ledges, and instead found that egg size was related to the amount of calcium in the diet, and egg shape was best predicted by adaptations for powerful flight.”

Remember, if you don’t speak French one egg is never un oeuf…

“Avian egg shape: form, function and evolution” by M. C. Stoddard, E. H. Yong, D. Akkaynak, C. Sheard, J. A. Tobias, and L. Mahadevan, Science, (2017).

It’s so easy to be distracted, especially when it’s 30 degrees Celsius in the shade, and you’re flagging after a long-winded drive to a reserve (today RSPB Ouse Washes at Welches Dam near Manea in Cambridgeshire). There seemed to be a reed bunting every 30 metres in the reeds along the waterway behind the flood bank and bird hides. There were a lot of barn swallows and a lot of sedge warblers and reed warblers.

The RSPB members’ book suggests there are some 13 different warbler species seen on the site, so when I saw this beautiful creature I leapt to the assumption that it was some kind of warbler…as ever it took my virtual ornithological mentor to correct my misconception – yellow wagtail (Motacilla flava). It’s a juvenile though hence the muted colours.

I must add though that I’d seen on on a post on the washes side of the flood bank close to some lapwings and had thought it looked like a wagtail. But, it was a long way off and on a hot and hazy day no zoom lens is going to correct for refractive abberations due to turbulent hot air rising.

Anyway, yellow wagtail it is, another one for the gallery.