Tundra Swan (C.c.bewickii)

My photos of the Bewick Swans at Arundel WWT, November 2016 and WWT Slimbridge Feb 2017. This is one of the most beautiful living creatures that I have ever seen. Along with my photos there is a basic summary of information about the species and for those wanting to explore the subject in-depth there is a selection of links and resources written by experts at the bottom of this page. This is a ‘Post in Progress’ and will be updated ‘as and when’ on an ad hoc basis – hopefully with more photos!

“It is one of the wildest and most elegant of our wildfowl”  (David Cabot)

img_4627-version-2

Taxonomy

The Bewick Swan (Cygnus columbianus bewickii) is the Palearctic sub-species of Tundra Swan, the other sub-species being the Nearctic North American Tundra Swan – Whistling Swan – (Cygnus columbianus columbianus). They are conspecific (based on DNA) and the most obvious difference is the amount of yellow on the bill – the latter having only minimal yellow patch below the eye, and the Whistler tends to be marginally larger and less compact. The Bewick gets it’s name from the wildlife artist Thomas Bewick who wrote a history of British birds.

A third potential sub-species exists in Eastern Siberia where the two sub species, Bewick and Whistler, are sometimes sympatric – overlapping – and hybridisation (the frequency of which is not known) sometimes occurs and so a third sub-species, Cygnus columbianus jankowskyi, has been proposed but generally rejected by most ornithological bodies – at least in every current source that I can find.

img_5287

Populations

The breeding territory of the Bewick extends across a vast tract of Artic Russia. The Northwest European wintering population, the group that the 5000 or so birds that winter in the UK every year come from, originates from a 29,000 strong flyway group that breeds from the Finno-Russian border to the Lena Delta in Siberia. The figure of 29,000 is taken from a survey in 1995 but a more recent census in 2010 suggests a figure of 18,000 and the population trend has decreased and is in decline overall since 1995.

img_4617

Another much larger population of these birds breed further east of the Lena Delta in the Arctic tundra, estimated at around 92,000 to 110.000 birds. This far eastern population of birds migrate southwards to winter in Japan, Korea and China. A third, much smaller population (c 1,000) is located between the two above, and they winter on the Caspian and Black Seas.

img_4570


I have adopted one of the Slimbridge Bewicks – Densel, a frequent winter visitor to Slimbridge

img_0300

Adopt a Bewick Swan Here (WWT)

“Graceful and bold, Densel is a handsome adult male Bewick’s Swan. He has been a regular winter resident at Slimbridge since 2007. He spends a lot of his time trying to impress his mate, Di and defending their territory in the Rushy Pen. They have been together since 2010 are we are very hopeful that this devoted couple will soon be returning with some lovely cygnets to thrill visitors to Slimbridge”


img_4640


Migration

They leave Siberia in September and arrive in Britain mid October (an epic journey of 2,500 miles), and also Holland and Germany. 30% of the total flyway population winter in Britain, with significant flocks (80% – 90%) of these concentrated in the east around the area of the Nene and Ouse Washes with less significant groupings in Western England, Wales and Ireland. The loss of traditional wetlands has resulted in the main bulk of the European wintering population being concentrated on just ten main sites across Europe.

img_4659

“The main wintering grounds of Bewick’s Swans in Europe are in the lowland areas of Northwestern Europe, from Denmark, Germany through the Netherlands, Belgium, to Northern France, Great Britain and Ireland. Small numbers occur in the Camargue, southern France. A small flock winters in the Evros/Meric delta of Greece and Turkey, respectively, which had previously been thought part of the Caspian wintering population. However, resightings of individuals ringed at the Wieringermeerpolder in the Netherlands in both the Evros delta and in the United Kingdom suggests that these birds are linked to the population wintering in Northwest Europe (W. Tijsen, pers. comm.). During the period 1996–2005, the majority of the population was recorded in the Netherlands (48–82%) and in Great Britain (17–32%) during mid-winter (Beekman et al., in prep). Numbers wintering in Ireland have decreased from 2,000–2,250 in the late 1970s to just three individuals in 2009. In the meantime, numbers wintering in Germany, which mainly occur along the lower reaches of the Ems River, have increased in general but with strong weather-related fluctuation (Beekman et al., in prep)”

[from AEWA Action Plan for Conservation]

img_9550-version-2

Of our 3 swans, the Bewick is the most sensitive to cold weather leading to extensive movement from the European mainland to Britain during severe weather on the continent, leading to fluctuations in numbers from year to year, which also conversely sometimes causes ‘short stopping’ – a decrease in numbers wintering in Britain due to more favourable conditions in Europe.

img_4534


Decline in Population

The real important figure though is the overall flyway population (the flyway is ‘the route between breeding and wintering areas taken by concentrations of migrating birds’ – and includes all staging , rest and feeding areas)

img_0310

Several reasons for this decline are currently being explored; climate change and the loss of wetlands, illegal hunting (the most recent studies have found that some 36% of living Bewick’s have shotgun pellets in their bodies), increasing numbers of man made obstacles such as overhead power lines and even wind farms on the migration flyway and also possible declines and fluctuations in breeding productivity on the tundra: The Bewick’s breeding cycle has been described as ‘a race against time’ on the Siberian tundra – a race against the elements with a long reproduction cycle and the short northern summer. These subjects are all explored in some detail in the resources linked at the bottom of this page.


img_4549-version-2


“The population increased dramatically during the late 1980s and early 1990s, from c. 10,000 in the mid-70s to 25,800 birds in 1990 and 29,000 in 1995 (Beekman 1997). However, a steep decline has taken place since the mid-1990s (Beekman 1997, Delany et al. 1999, Delany & Scott 2006, Wetlands International 2008); the population was estimated at 21,500 birds in 2005, and numbers have continued declining since then (Rees & Beekman 2010). The reason for the population trends and particularly the recent decrease in numbers – whether this is due to conditions on the breeding grounds, staging areas or wintering sites, or to a combination of factors – is unclear”

[AEWA Action Plan for Conservation]


img_4651


img_2585

A handy guide produced by Flight of the Swans / WWT for recognising the difference between the three species of European Swans; Bewick Whooper and Mute

(PdF opens in new window)

img_4358-version-2
Whooper Swan for Comparison (Old Bedford River – Feb 2017)

img_4687


IMG_6609

Sir Peter Scotts statue with Bewick Swan at London WWT

wwt_swan_twitter_background_1

“Being able to identify every individual by the pattern in it’s bill, which is as variable as human fingerprints but much more obvious, has enabled us to build up a detailed record of some 3,700 swans since Maud, which have visited the pond in front of the studio window up to the end of 1979. As I write this I am sitting in a tower which we have added to our house overlooking the pond now inevitably called ‘Swan Lake’, and there are at this moment more than 200 Bewick’s Swans shining brightly against the dark water under the floodlights. It is quarter past five on a December evening”

[Extract from “Observations of Wildlife” Sir Peter Scott 1980]


img_9544

Most of the British visitors begin the journey home before the end of March; an account of which can be found in the Action Plan for Conservation by the AEWA which also provides excellent background info on the Bewick:


aewa

AEWA Action Plan for The Conservation of The Bewick Swan

(Opens Pdf in new window)


img_4631-version-2


London WWT Resident Bewick cygnets – May 2017

Two Bewick’s resident at London WWT – born from a resident couple living in Wales. At the time of writing they were 9 months old and still displaying the slight grey colour of a juvenile

IMG_9668

IMG_9666

IMG_9682


(Below) London WWT Resident Bewick cygnets – October 2017

IMG_0805.JPG

IMG_0791.JPG

IMG_0627.jpg


Rees

Eileen Rees tells the story of these birds in rich detail. Rees discusses their biology in full, with sections on population and distribution, breeding biology, wintering behaviour, food and feeding ecology, taxonomy and phylogeny, migration, and  conservation; much original research is included, and there is frequent reference to the Bewick’s sibling subspecies, the Tundra Swan (Whistler) of North America

WWT London – May 2017


OTHER LINKS AND RESOURCES


fullsizerender

Goose News Issue 15 Autumn 2016 – pages 11-14: “Is poor productivity behind the Bewick’s Swan population decline?” (PdF File)


fullsizerender

Bewick Swans: a population in decline – (Rees and Beekman) published in British Birds 103 (PdF File)


fullsizerender

Bewick’s Swan – Waterbird Review Series – Joint Nature Conservation Committee (PdF File)


The Flight of The Swans Project

The journey of the Bewick’s to the UK from the Arctic tundra in the autumn has been followed very recently in the most dramatic and adventurous project designed to further understanding and cross border cooperation in the conservation of this species

Flight of The Swans

Which was covered in The Guardian:

https://www.theguardian.com/environment/2016/sep/19/sacha-dench-british-conservationist-takes-to-the-skies-for-4500-mile-migration-with-swans


SOURCES:

David Cabot, Wildfowl, 2009

Wetlands International (2017) “Waterbird Population Estimates”

WeBS Report 2011

RSPB Handbook of British Birds, Forth Edition

The Bird Atlas 2007-2011

International Single Species Action Plan for the Conservation of the Northwest European Population of Bewick’s Swan (Cygnus columbianus bewickii). AEWA Technical Series No. 44.Bonn, Germany.

WWT Waterbird Monitoring

‘Goose News’ Issue 15 – WWT Waterbird Monitoring 2016

Sebastien Reeber, Wildfowl of Europe, Asia and North America, 2015

‘Waterlife – The Magazine of the Wildfowl and Wetlands Trust’ (119 – Jan/ Mar 2017)


img_9564