Cormorant question (1 Viewer)

[Bluetail]

I thought no one was really sure why Cormorants held out their wings. Certainly some doubt that they do it to dry them - especially since they've been seen doing it in the rain. I even saw that myself once (at Radipole). There used to be a suggestion that the wing-spreading was perhaps to aid digestion. Not sure that theory was ever very popular and I haven't kept up with the arguments.

 

[Michael Frankis]

Hi Jason,

They'll hold their wings out in the rain, and they'll also hold their wings out even when they've caught nothing and have nothing to digest.

Let's face it, they are FISHERMEN . . .















"You should've seen the one that got away . . .


it was this big . . . .



HONEST!!!"

 

[mike60]

Maybe no one told the cormorants that drying their wings in the rain doesnt really work
Animals in nature often behave in set patterns, even when its innaproriate to do so.

 

[Keith Reeder]

Cormorants do present some interesting dilemmas, don't they?

As a birder, it's hard not to be impressed by the critters - they are clearly filling their niche very effectively, and I enjoy watching them immensely - common birds or not.

But as a(nother) angler, I can't help but resent the same birds for eating "my" fish!

Of course, there has also been an (apparent) increase in the numbers of other fish eating birds in this part of the world - goosander seem to becoming seasonally as common on some rivers as herring gulls - and I wonder what might be the cause of that influx - assuming there has been an actual increase, and not simply the paranoid imaginings of worried anglers!

I actually fish the "Brasspond" mentioned by Stevie Evans and hadn't realised the cormorant presence was quite as significant - I'll have a closer look next time...

 

[tony.hetheringt]

Hi Tony,

They 'deliberately' don't have waterproof feathers (more accurately, have evolved not to). If the feathers get wet, it means they don't trap any air when they dive. That means they can dive deeper, faster, and chase fish more efficiently, because they're not having to fight against the buoyancy of air trapped in their feathers.

The downside is that they need to eat more food to supply the body warmth when living in cold water. But it is still a successful strategy.

Michael

Hi again Michael,
If I say the word penguins, should the same not apply,or do penguins have
feathers and/or blubber?
Regards Tony

 

[Michael Frankis]

Hi Tony,

They've gone down the other route - maximum waterproofing to maximise energy efficiency. So they're less adept at catching fish, but don't need to eat so much, either. Both strategies work, though the penguin/auk strategy is probably the better one in colder waters; cormorants evolved in warmer areas. They have also proved fairly successful in colonising cool waters, but not so well as penguins or auks. Equally, you don't get penguins or auks in warm waters, their strategy is less competitive there.

Michael

 

[tony.hetheringt]

Thanks Michael,I'm no longer dubious.
All the best Tony