[Charlie600]

I had the opportunity to photograph Long-tailed Ducks last weekend and quite a few of the shots I took showed what appeared to be well defined tooth like structures. I spent a lot of time this week on the web trying to educate myself. I found a number of references to lamellae - hair like structures and Pecten - comb like structures. Function was related to preening and filtering food. The information I found was rather sketchy and vague and I am still having a hard time getting my head around this observation. The "teeth" on these birds don't look like they would be much use for filtering. If I am correct, these birds include eels and fish in their diet. It seems that the structure would function more for gripping than filtering. I would appreciate comments and references to information. It would be really interesting to hear from someone who has actually handled one of these ducks. Are the lamellae as sharp and as hard as they look in the photo?

[KCFoggin]

No not teeth but the inside of their bills has severed edges to grab bugs and underwater weed in the water. Would be nice to see a wide grin from them though

[fugl]

No duck has “true teeth”, of course, though some have specialized adaptations for filtering (e.g., shovelers) or for the gripping of large slippery prey (e.g., mergansers). I just looked up LT Duck on BNA-online, but found no reference to “lamellae” or “teeth” except a bare mention of the former in connection with the bill of the duckling. According to BNA, LT Ducks have a varied diet including small prey of various kinds as well as fish & mollusks, so either of the suggested functions—filtering or gripping—would seem to be a possibility.

Anyway, very interesting photo. Thanks for posting it. With luck someone will come along with definite information about the function of the “teeth”.

[Fozzybear]

I saw this on Mallards when I photographed them some time ago - can be quite bizarre when you see them at first! Here's a close view:

http://www.flickr.com/photos/paulforsdick/3280954359/

I guess that it's to help them tear off and rip up vegetation since a smooth bill wouldn't give them that good a grip on the wet weeds they often eat.

[Jabberwocky]

Here's a shot of a Goosander (common merganser) I got last year. Shame its not quite in focus but you can see why they're called sawbils.

Lewis

[Fozzybear]

Yes it really is very clear on Goosanders, I'd noticed that on the ones I see here too.