bare-faced or sharp-tailed? (1 Viewer)

Could someone tell me the differences between the bare-faced ibis(phimosus infuscatus) and the sharp-tailed ibis(cercibis oxycerca)? I have seen one of them several times, but from a considerable distance, and I was not able to tell which one it was. I also think I saw some white on its wing while it was flying.

Chris,
From what I can see the Phimosus is completely glabrous from the forehead, running in back of the eye and including the throat. The zone looks pinkish until you get to the bill insertion and the bill is kind of straw-yellow color. The legs looks very light pink. I don't have in-flight pics so can't speak to the white you mentioned, however, the bird plumage looks basically black but I can discern that the primaries look to be a kind of black with greenish reflections. The Cercibis seems to have a circular glabrous zone (pinkish) around the eye but the forehead doesn't seem to be glabrous. Also basically black bird. The legs looks to be a darker color than the Phimosus. You should remember, however, that in your zone also possible are Plegadis falcinellus as well as Plegadis chihi.

If seeing the individual well, the extent of bare parts can be used as a good id-feature to differentiate the two species, as mentioned by cuckooroller. However, legs are NOT usefull, both species usually having reddish legs, that may (as always in these waterbirds) seem darker due to mud etc. From a distance there is another good feature, that is, at least with a bit of practice (and what I used all the time in Brazil where both occur) very good: Tail versus closed wing. Bare-faced (Whispering) Ibis has a tail that roughly fits with the length of the closed wing. The Sharp-tailed has a long tail, that obviously sticks out far beyond the closed wing. Much more than in any other ibis-species (American or not). Also, the Sharp-tailed Ibis is much bigger than the Bare-faced, but this is of course a feature that can be hard to use.

In flight the two can be hard to seperate from afar, but Bare-faced being a much smaller bird, has fast wing-beats for an ibis. Quite the opposite is the case in the heavy Sharp-tailed.

Voices of the two are very different, and I have *never* heard the Bare-faced vocalizing in flight, which the Sharp-tailed often does. The voice of the Bare-faced is not very loud, hence the old name "whispering". I will, for obvious reasons, not try to repeat the voice of any of the two...!

Also, often (usually) you would see the Bare-faced Ibis in flocks whereas the Sharp-tailed is much more likely to be found in singles, pairs or trios (max would probably be four).

White in the wing??? I have never seen or heard of any individuals of the species showing white??? Both adults and juv's are dark (at least that is my experiance).

Rasmus Boegh

...And on the two Plegadis (has chihi been recorded regularly in Guyana, there doesn't seem to be any certain records for nearby Venezuela?); they are very different, from the two species mentioned above. All other ibises in the Americas have longer legs than the two VERY short-legged Bare-faced and Sharp-tailed. Of course they also lack the bare parts on the head.

One important note... non-breeding (and juv.) Plegadis often show at least some whitish-grey on the underside/neck...!

Unless experianced in these species perhaps Green Ibis is another possibility, though it is usually more of a forest species.

Rasmus

Rasmus Boegh said:

...And on the two Plegadis (has chihi been recorded regularly in Guyana, there doesn't seem to be any certain records for nearby Venezuela?); they are very different, from the two species mentioned above. All other ibises in the Americas have longer legs than the two VERY short-legged Bare-faced and Sharp-tailed. Of course they also lack the bare parts on the head.

One important note... non-breeding (and juv.) Plegadis often show at least some whitish-grey on the underside/neck...!

Unless experianced in these species perhaps Green Ibis is another possibility, though it is usually more of a forest species.

Rasmus

Click to expand...

Hi Rasmus,

I was just going to ask you about the Green Ibis. I couldn't really figure out from my books if it ranged there. I guess by inference with what my books say it ranges from Costa Rica south and including most of S. America to ne Argentina.

Thanks for the tips! I am almost certain that it was either the whispering or sharp-tailed because I saw the red on the face. Do you have any recording of the vocalizations? I heard it while it was flying about in a field , and I would be able to recognize it if I heard it. It also seemed to be by itself the times I saw it, except this morning I saw two of them flying over. When I saw them flying, they reminded me of geese or something like that. It was flying quite high and pretty fast, to high for my 7x35 Stellars to identify.

Nope, sorry; I don't have any recordings of Sharp-tailed, but the description in "Birds of Venezuela" is good. There is a recording of Bare-faced on the "Birds of Venezuela" cd (but it is obviously copywrited so I can't just pass it on). However, here are some comments, based on your second reply:

"flying quite high"

- I have never seen a "high flying" (though that is obviously a subjective statement; what is "quite high"?) Sharp-tailed Ibis. They are usually rather shy... and so is Green.

"pretty fast"

- Another subjective statement, but generally Sharp-tailed would be considered a slow flying ibis (contrary to the Bare-faced)... However this is compared to other ibis-sp., so, unless you have experiance with them, it is hard to say anything...

"heard it while it was flying about in a field"

- If you heard it at from any sort of distance, you can almost certainly rule out Bare-faced. Again, see my first thread on this subject.

"two of them"

- The Bare-faced Ibis is almost always found in big groups.

So, some of the above notes are obviously somewhat contrary! Are you sure you saw the red face (also note that Sharp-tailed usually has a small greyish patch on the chin)? - And, if so, are you sure the first individual you heard was the same species as the two you later saw flying high overhead? Did you see red on the head in both the first and also the two later individuals? Often several species of ibises occur together... I have seen 5 different species of Ibis together in one small pond (!) and, in the Llanos of Venezuala, Sharp-tailed and Bare-faced Ibis can sometimes be seen together. It is perhaps important to note, that Sharp-tailed rarely (if ever) occurs in big (mixed or uni-species) waterfowl aggregations.

Anyways, in short; if all your observations are right, I would guess that you saw two different species. The first lone calling individual being a Bare-faced (I am guessing that you saw the red on the head in this individual), and the second two high flying individuals would be Plegadis (it would be very hard to see any red throat patch if the birds are flying high. Also judging from you mentioning "white" in the flying birds). And, as mentioned previosly, a Plegadis seen in Guyana would almost certainly be a Glossy Ibis. Still, these are nothing but guesses, and you may very well have to make a second visit to the spot...

Last question; did you notice if the legs extented beyond the tail in the flying birds? If so, you can surely pin them down as Plegadis, as Sharp-tailed, Bare-faced and Green Ibis all have legs that DO NOT extent further out than the tail in flight.

Rasmus

The two that I saw today were not flying extremely high, but high enough for me to not be able to ID them. I guess I shouldn't have said they were flying pretty fast, I was saying that in relation to flying ponderously slow. As I was not able to see the two well, I am not certain they were the same as the first one, but they certainly reminded me of it. I did not see the red face on the pair, but again, they looked similar. I had not seen any ibises until a few days ago, then, all of a sudden, I see three in a few days time! So naturally they looked the same, because they are the only ones have ever seen. I am not sure I saw white in the wings, it could have been sky showing through. My checklist of the birds of Guyana by Braun, Finch, Robbins, and Schmidt has only one Plegadis, (Plegadis falcinellus) and it says that there are only sight records of it, this one gave me the idea of being kind of common. Sorry, I did not notice if the legs extended beyond the tail. See what you can do with this info...

Yes, in many areas of Guyana I would presume that Glossy Ibis (P. falcinellus)
is the commonest Ibis. I say "presume" because I have birded just about all the nearby countries, but not Guyana itself. But, I guess you will have to appeace yourself with the ones you saw as being "perhaps id'ed".

So, well, yes, it is rather common, but that doen't make it any less amazing...! I would never "trade" my very first Ibis sighting (being a white) for any of the other much rarer Ibis species I have seen since!!! The first still stands out... (I am - or have become - a bit of a "world bird family collector").

And, with all new species/groups it takes a bit of getting used to. I still remember my massive Egretta-id problems not that many years ago. Now I have seen thousands, and can (...almost...) id them with my eyes closed!

At least now you know some of the things to look for next time you come across one of those dark ibises...

Rasmus

I'm sorry, I guess I didn't make myself clear. I meant to say that the ones I saw were the common ones. I don't think it was the glossy, because I am sure that it had a red face. I will try to go back and see it again, then get back to you with what I saw.