In this video, we are going to look at two initially similar waders
Curlew and Whimbrel.
Both are large for waders, and have stout legs,
grey brown bodies and distinctive downcurved bills.
So how can we tell these two apart?
As so often happens with two similar species, one is much more common and familiar,
and being confident in identifying this one, the Curlew, will greatly help us pick out the less
familiar Whimbrel when encountered.
Curlew is a common, well known, resident bird.
It is big with a body size approaching that of Herring Gull.
It is found principally around our coasts and wetland sites in winter,
when some 150,000 birds are found in the Country.
100,000 pairs breed and these are found in a range of habitats, from coastal
to inland grass, wetlands, moors and uplands.
The plumage in all seasons can almost be described as bland.
Dark streaked, grey/brown uppers merging to a white belly.
The face is plain and the steel grey legs medium in length and stocky.
The most obvious feature of Curlew is, of course, the beak which is long and downcurved.
Among the larger waders, this feature is shared solely with Whimbrel.
It is worth noting however, that relative bill length is sometimes quoted as an ID feature
but this can be very misleading as bill length in both species varies with sex and age.
With Curlew, however, the curve appears constant and gradual throughout the whole length of the bill.
Whimbrel is a significantly smaller bird, with a body size about that of a Common Gull.
Whimbrel are much rarer, only a handful present in the winter and some 500 pairs breed on
mountainous bogs and moors in the far North of Scotland
but several thousand birds pass through on passage in April and May
and again in late summer and autumn.
Fieldguides and illustrations always focus on the two brown crown stripes on Whimbrel
but in the field without excellent views
these can actually be frustratingly hard to see.
Whimbrel can sometimes seem surprisingly plain faced, especially if you are expecting a stripey faced beauty.
If you do see the stripes and the apparent supercilium, then you have clinched the ID, although
do be aware some Curlew can occasionally have unexpectedly obvious superciliums
seemingly just to confuse us.
Overall, Whimbrel gives the impression of a small dark Curlew
and one of the best visual clues
is that bill which, unlike in Curlew, appears as a straight bill with a bent end.
The curve is not even and continuous.
Both species look similar in flight, dark birds above with a white rump and v-shaped back.
If the apparent size is not obvious or the bill can't be seen,
one difference that seems to be constant in the field
is that Curlew upper wings seem to grade gradually
from the body colour to the darker outer feathers
whereas Whimbrel have a much more abrupt pattern,
the whole outer wing appearing much darker than the inner.
Whimbrel also fly with much faster wingbeats than Curlew,
again, a feature that is easy to pick out
when you are familiar with Curlew.
Since views of both species, considering their habitats, are rarely close enough to make out many details,
you'll be glad to learn there is something else that will help us identify these two species
and that is their songs and calls.
Curlew are quite noisy birds, uttering calls on the ground and in the air.
[calls]
They make a range of sounds but the distinctive, beautiful, melancholy 'cour-lii' is unique to this species
and is indeed a characteristic sound of our wild habitats.
Their contact or flight call is a single note, a drawn out piping whistle, which to me always
sounds distressed.
Sometimes uttered singly, Curlew also string together 3 or 5 of these notes, with a slow rhythm.
Whimbrel do make some similar sounds to Curlew but they also have a distinctive contact or flight call.
[Calls]
This call once known, will often alert you to the presence of Whimbrel and it can sometimes
be picked out from birds migrating high over- head.
[calls]
Again it is a whistle but it is less fluting more confident sounding, not
worried or distressed.
Whimbrel often repeat this quickly as a series of notes or even join it together
in a trill.
It may help to remember an old name for Whimbrel is 'Seven Whistler'.
[calls]
If you are lucky enough to hear either species sing, again, you can tell them apart.
Curlew song is a familiar rising series of whistles, which accelerate and merge into
a beautiful bubbling trill.
It's one of my favourite bird sounds and Curlew song is evocative of all our wild places.
Whimbrel song, only likely to be heard on the breeding ground, starts in a similar
manner to Curlew with those same rising notes but it then descends into a rapid trill on
one note, similar in fact to the call and lacking the bubbling flutey elements of Curlew song.
It can almost be described as stammering.