Mute Swan - original distribution? (1 Viewer)

[Gonçalo Elias]

Hi all,

Mute Swans have expanded in recent decades (or centuries), mainly as a result of domestic / feral / introduced popoulations. However, as far as I know, this species is native to Europe and nowadays it is not always easy to tell feral birds from wild ones.

Is the original distribution known? I mean, before domestication began, where did this species occur naturally?

 

[Paul Chapman]

I have debated this in the past. eBird gave me native Mute Swan in Croatia but a friend suggested that I needed to go to Kazakhstan & another ticked it in South Korea...

Attached excerpts from Saunders 1880ish, Migration Atlas, EBBA2 & eBird Species Map if I remember correctly from that discussion. eBird's assessment of Mute Swan range - Cat C in orange & A in purple.

BOURC have a Category A categorisation amongst other categorisations which surprised me... Presumably they consider that there are vagrants from the native range? eBird's assessment is simply wrong as far as I can ascertain.

All the best

Paul

 

[Gonçalo Elias]

Thanks a lot Paul.

 

[THE_FERN]

Thanks a lot Paul.

The mute swan is a highly educated and political bird. It understands national borders such that (according to ebird), mute swans in Iberia are careful to ensure that they're only introduced and not truly wild. The population in Ireland exercises similar immigration controls.

Basically, these ebird maps are complete nonsense...

The question you ask is interesting, but I suspect it's like asking "where is the ginko native?" So many introductions and translocations it's now impossible to tell. Perhaps DNA would help...

 

[Gonçalo Elias]

Thanks THE FERN.

Indeed I don't know why the swan is marked as exotic in some countries but not in others. In the case of Spain, there have been cases of wintering birds that had been ringed in central-eastern Europe, so migrant individuals do occur.

 

[davercox]

I know Wikipedia is not always reliable but surely it can't be wrong when it says "Mute swan subfossils, 6,000 years old, have been found in post-glacial peat beds of East Anglia, Great Britain. They have been recorded from Ireland east to Portugal and Italy, and from France 13,000 BP (Desbrosse and Mourer-Chauvire 1972–1973)." And surely nobody was introducing them in palaeolithic or mesolithic times ?

 

[Dave Boyle]

I asked Chris Perrins about this years ago & he was surprised at the suggestion that they weren't native to the UK

 

[THE_FERN]

I asked Chris Perrins about this years ago & he was surprised at the suggestion that they weren't native to the UK

Yes why wouldn't they be? It's a waterbird and the UK is, well, wet. (I mean habitat not obviously different to their supposed native distribution of course)