[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]

Re: Cormorants, anhingas & soaked feathers



I recently had to deflesh a nice fresh cormorant for
an osteology class. I haven't had the chance to watch
a ton of cormorant behavior, but I've never seen these
birds dive from the air, like some gulls and soaring
birds do. They always dive from the surface of the
water, like loons and mergansers. As far as I can
remember, most air-diving birds don't have water
repellant feathers either (correct me if I'm wrong). I
would imagine that, when swimming on the surface, a
cormorant's lower half would become soaked with water.
Perhaps this would help to weight the bird down and
improve balance during the first few seconds of a
dive, while the feathers on the upper half were
absorbing water? You've got me stumped. I've always
wondered whether or not feathered dinosaurs and fuzzy
pterosaurs would have to take some serious drying time
out after taking a swim! 

Anhingas and cormorants are both Pelicaniformes. Does
the lack of waterproof feathers extend throughout the
order?

Michelle Pinsdorf
drakeducaine@yahoo.com

--- Brian Lauret <zthemanvirus@hotmail.com> wrote:
> As we all know (I presume), cormorants and anhingas
> lack water-repellent 
> plumage. That is, diving means they'll get soaked to
> the skin and will have 
> to dry their feathers afterwards.
> 
> The latter thing takes time while the succes of the
> dive isn't even assured. 
> In my logic, this puts cormorants and anhingas at a
> considerable 
> disadvantage compared to their waterproof
> competitors.
> The diving itself doesn't seem like the reason for
> the strange strategy 
> employed by these birds. After all,
> loons,grebes,auks and mergansers all 
> dive succesfully with their waterrepellent plumage.
> 
> So I wonder, what could be the use of getting soaked
> to the skin and having 
> to dry up, what makes it such a succesful strategy
> and why could it have 
> evolved in the first place (or: why didn't
> waterproof plumage evolve in 
> cormorants and anhingas?
> 
> Brian
> 
>
_________________________________________________________________
> Nooit ongewenste berichten ontvangen: gebruik MSN
> Messenger 
> http://messenger.msn.nl/
> 
> 

__________________________________________________
Do You Yahoo!?
Tired of spam?  Yahoo! Mail has the best spam protection around 
http://mail.yahoo.com