UKC

I was watching cygnets on the canal today. As they tried to mug me for bread they were paddling around with one foot tucked up onto their back. But why?

Canal speed restrictions? 

I would also be interested to know the real answer 

they're showing off - it's a learned skill - the j-stroke, as all 'canadian' paddlers must know

It's not restricted to cygnets, adult swans do it too.  It is to do with temperature regulation, but of the swan as a whole rather its feet.  More info here: https://swanlovers.net/these-are-common-mute-swan-behaviors-you-will-see/

Swans with hot feet. Who'd have thought? The cygnets still have thick downy coats so cooling off would make sense. Especially as the sun was out.

Probs holding a weapon ready to mug you. Adults just break your legs. 

Some birds, particularly water birds, have a clever heat exchanger system in their legs called the retia mirabilia. It consists of a network of very fine blood vessels intertwined with each other. Warm blood from the body at about 40C gives up much of its heat to cold blood returning from the feet. By the time blood reaches their feet it may be as cold as 5-6C.

Water birds still get cold feet but because the temperature gradient between their feet and the environment is much smaller they lose far less heat through their feet than might be expected. The system can also work the other way round in hot weather. Sphincter muscles effectively close off the retia mirabilia allowing warm blood into the feet. Large amounts of excess heat can then be lost through the feet.

Are there any recorded instances of this or is it an urban myth?  

Urban myth I think. One once had a go at my brother, ripping his flimsy jacket with its beak. 

In my experience you have to watch your berries in the company of avians

BC is just getting confused there, it's a myth.  Swans break your arms, not your legs, everyone knows that.

Little known fact, but of all arms broken by Swans, 89% of them were the left one and the other 12% the right.
How weird is that?

There’s a place in St Helens, which has a high rate of inter cousin marriage, resulting in most people having two or more left arms. So not that weird really. 

I sometimes wish I had three arms as it would mean I could turn the pages...

Dunno, but what a great route name.

I might add that it's only GROWN MEN who get broken arms. I've observed women and children milling around swans which then turn into hissing, flapping maniacs when a grown man approaches

When you’ve gone out of view, I reckon the women and children stop hissing and flapping. 

This chap is into his 11th pair of arms.  It should be banned really, taking risks like that.  Horrible birds!   I feel fear of seeing something dreadful every time I cycle past him with those things ...

https://www.itv.com/news/border/2021-04-15/swan-lake-meet-the-paddle-boarde...

will no one think of the children? Or cygnets?

I’ve heard that bloke has developed a very close and personal ‘relationship’ with those cygnets, and when he gets caught he  uses the excuse that he is looking for his cygnet ring. Which is probably true. 

You've got some neck making allegations like that.

Tangentially related to the humans-vs-birds thing: https://xkcd.com/2090/

Not so tangentially related: https://www.theguardian.com/environment/2023/jul/14/time-to-end-war-on-bird...