Lovely day at Horrid Hill

7 Redshank, 6 Turnstone, 1 Dunlin, Curlew heard, 6 Oystercatcher, 70 Wigeon, 20 Pintail, 100+ Teal, 150 Black-headed Gull, 2 Magpie.

Motney Hill

Teal out with the Shelduck at first, then half a dozen Wigeon.

Black-headed Gulls yielded no Med Gulls despite searching. Many of them with apparently dark bills and darkening heads.

A couple of Redshanks. A Pipit.

Moorhen and a pair of Mallard.

Woodpigeon. Wrens. 

Turnstones at Lower Halstow

Black Swan at Leybourne

I was just thinking its all same birds as normal, and a black swan appeared!

Aythya fuligula - Tufted Duck

Males

On the Fishing Lake by the cafe block at Haysden Country Park on the 27th of January 2014, there were a couple of nice Tufted Ducks, Aythya fuligula, 2 males. This bird below, one of the two, does not have an obvious crest, but I think must still be older than a first winter juvenile, as there is no barring on the flanks. The water droplets still clinging to the feathers may indicate that the bird has recently surfaced and the crest may then be slicked down in consequence.

Other interesting ID features of Tufted Ducks are the interestingly shaped head with the high forehead on a relatively narrow neck. The bill has a good solid black tip or nail (across the cross-section of the bill, looking as though it "has been dipped in ink"). There is more than a hint of a whitish stripe across the front of the bill of this bird, contrasting with the light blue-grey on the rear part of the bill.  This feature is very variable apparently. 

The bird is said to sit low in the water but with its tail above the surface, and I think I would agree with this from this picture to some extent - it looks as though its sitting a bit lower in the water at the moment, perhaps after a dive. It may be that the tail is being splayed out and held just pressing down on the surface of the water. Deep yellow eye, perhaps slightly out of focus.  The contrast between the dark wing and the white sides is nice and distinct, a beautiful bird indeed, moving well across the water!.

On the main Gravel Pit, Barden Lake, other individuals were keeping themselves out of trouble. This one looks very much at rest, but with its eyes open! I think that the wings are most easily seen from this angle, with the two sets of primary feathers forming a valley down the back between the two wings. It also looks to me as though the flank feathers somewhat overlie the sides of the wings, giving that fringed effect to the rear of the white sides. The tail sits slightly cocked in this picture, with the bird sitting still on the siurface of the water.

A drake tufted duck looks very seriously at me, as I stand on the bank at Barden photographing him, on the 19th of January 2013!

This is the same male, on the same day, virtually the same attitude, at 2 different crops.

It's amazing how the droplets of water remain attached to the feathers!

Females

The females show the same amount of darkening at the tip of the biill, with sometimes a little light band just behind. The main part of the bill is a lot darker in the female than in the male. Some of the females show a scaup-like white patch at the base of the bill, although not quite so extensive, and I rather think quite a lot of them show some degree of lighter brown in that area, like the one in the duck below. This duck, 27th January 2014, is in winter breeding plumage, and the bird will probably now undergo a partial moult just before nesting.



This female, at Barden on 31st January 2014, by contrast appears to have only minimal lightening of the feathers at the base of the bill.

While this one has a little bit more. This one also has the white triangle under the tail, as though its gone early (1st February, 2014) into the summer plumage. There may be more to be thought about here.

Here is a quizzical look from this Barden female (1st February 2014):

This picture, taken at         on the 2nd of March 2013, shows the female (behind) in nesting plumage with the light triangle at the rear of the flank. This is very early in the year, very odd indeed. The male may be dipping its head slightly downwards in display. Quite a golden light that afternoon! See how much lighter the male bill is.

First Year

There is some support for the idea that first year males once they finish their late summer moult can still be distinguished from the adult males by some remaining barring on the flanks. The extent of this is unclear, but very obvious according to pictures from the Chichester Harbour Ornithological Group. Here is a male at Barden on the 31st of January 2014 that is showing just one blackish mark in the middle of the flank. Definitely a male from the length of the crest in my view, although it may not be excessively long and perhaps just a glitch, as it may just be one feather. The colour of the darkening is right but the extent appears pretty limited.

So the question is, where are all the first year birds?

and the answer is, they may be there if you look! This was a  bird on its own by Coot Point on the very same day, that I had earlier ignored (!), and when you look at it, it is either dirty or somewhat dark on its flanks - a likely first year bird then, and perhaps the slightly shorter crest as well as the slightly lone behaviour might back that idea up!

Feeding

According to the BTO, "the rapid expansion of the Tufted Duck in Britain during the late 19th/early 20th century is probably due to the colonisation of Britain by Zebra Mussels (brought into London docks in the 1820s)".  The birds are omnivorous, feeding mainly on mussels, insects and plant material taken from the muddy bottoms of the water bodies they are on, diving anywhere between 4 - 15 metres down. It breeds better if there aren't excessive numbers of fish. 

This male at Barden on the      seems to have this lump stuck to the inner surfaces of its bill. Most of the material collected from the bottom of the lake is eaten beneath the surface.

Behaviour

In this picture, taken at Barden on the 19th January 2013, the tail of this male is clearly seen to be splayed out, and apparently pressed down against the water surface. I would imagine that this would tend to stabilise pitch while the duck is paddling forward, keeping the head down and steady, rather than pitching up and down. Incidentally here you can see that the tail is actually a dull black in comparison to the true black of the rest of the plumage.

In contrast, looking at this heavily cropped picture taken on the 2nd of March 2013 at Barden, the tail is held horizontally above the surface of the water, and not particularly splayed. Coincidentally or not, this bird is completely still, not swimming forward at all. 

Diving

This male, on the 31st January 2014, is rolling to its right as it dives. The tail has been pushed downwards nearly vertically to act as a brake and aileron, as the feet get to work propelling the duck into the dive. You cam see the disturbance in the water rear and left of the duck of the first stroke.

  


Breeding

These two birds look as though they have paired up, with the female in complete winter breeding plumage - I cannot see the paler patch at the rear of the flank of the summer nesting plumage.  The birds were cruising down the ditch towards the cafe car park at Leybourne Lakes on the 18th March 2013. There is an amazing size difference between this male and female. I do wonder why the make is holding his head so high, maybe this is a display related to neck thickening. The eye is quite obvious, and perhaps the male has closed its pupil to increase the iris size.

The plumage on the female is the general winter breeding plumage. There will be a post-breeding moult before nesting of the body and tertials March-May. Nesting and incubation would then often be in late May, with incubation through to late June, and taking care of the young through the next about 50 days. Then there is a moult of the wings (and tail)  about July-August when she will be flightless.  

Rough weather

This female is braving the waves at Barden on the 31st January, 2014, and the water is demonstrating its strong surface tension as it slops around her chest.

Its interesting to see how far back this same female is holding her head on her body.

Pressures

There is increasing pressure to develop many existing water spaces in Britain for recreational activities. This trend will increase disturbance to water bird populations. This paper considers these problems and suggests the sorts of information which are needed for formulating multi-purpose amenity plans for water spaces, where a conservation interest exists. The study at the Brent Reservoir in north-west London has shown that a few species of wildfowl, e.g. Anas platyrhynchos, Aythya fuligula, Aythya ferina, still use the reservoir in autumn and winter despite an intensification of sailing activities. This use and the successful breeding of Podiceps cristatus and other species of water birds depends on the existence of a large enough part of the reservoir which is shallow and marshy and not accessible to boats. As there is some suggestion that larger flocks are more sensitive to disturbance than smaller ones, refuges may be made more effective by proper screening. 

Sailing on reservoirs and its effects on water birds Original Research Article Biological Conservation, Volume 11, Issue 1, January 1977, Pages 49-58 L.A. Batten

Population

The Tufted Duck colonised the UK as a breeding bird in 1849, assisted by the arrival of the Zebra Mussel and increasing eutrophication of our natural waters a couple of decades before. Its breeding and winter populations are still increasing and it is interesting to speculate on its continued success. In Northern Europe its population in Northern Europe has tailed off a bit, and the NI wintering population has correspondingly decreased as well.