Thank you!Front one looks like; bill shape, border at forehead, size etc
Thanks so much!I agree, the front bird is a Trumpeter.
Don't think this is right. Sibley says that adult trumpeter never have yellow loral line that 2 of the birds exhibit. Also, suggest there's perspective at play here. For me the back left bird [for example] is appreciably smaller although I can see how might it appear not to be.As all birds appear to be the same size, assume all are Trumpeter as Tundra should be appreciably smaller.
Trumpeter swan: 'rarely shows yellow on lores' (big Sibley, 2nd edn).Sibley says that adult trumpeter never have yellow loral line that 2 of the birds exhibit.
Fair enough. I have Sibley 1 which says opposite...Trumpeter swan: 'rarely shows yellow on lores' (big Sibley, 2nd edn).
For me the front bird has a bill/forehead border which ends in a point (most clear in first photo). For tundra this should be rounded. You'll note my comment about size earlier too.The shape and clarity of the loral yellow spot is better for Tundra swan. In the Trumpeter swans I have seen photos of, this spot was very small, or where larger , it was somewhat mixed with black areas
Here are some Trumpeter swan examples showing yellow on the lores:
So I think the rear birds are Tundra swans.
The front bird is the most difficult . A few Tundra swans show an all black bill:
But there is a slight overlap in size and weight for the two species meaning some large male tundra swans can be larger than a small female trumpeter swan. The front bird does not seem larger to me than the other two- but from what I said before that wouldn´t necessarily exclude a Trumpeter swan. However, it is turning its head very slightly in an angle towards us, which alteres head and bill profile a bit.
I think this is also a Tundra swan
THE FERN and querty5,
Yes, I had considereed these points (bill/forehead border ending in point or rounded + eyes more or less distinct from bill) also, but I find them very difficult to judge for single birds, especially on photos. These differences seem generally present, but there seems to be quite a lot of individual variation.
. Also the pink at the mandible edge which is also mentioned as a separating point, is not fully reliable as individuals in both species can show it , though the one more frequently than the other . But look here:
So what do you think of this bird :
My personal view of the first link here is that the bill edge is actually rounded and the photo a bit misleading. The second looks more clearly pointed but not as much as trumpeter (or indeed for me front bird photo 1).THE FERN and querty5,
Yes, I had considereed these points (bill/forehead border ending in point or rounded + eyes more or less distinct from bill) also, but I find them very difficult to judge for single birds, especially on photos. These differences seem generally present, but there seems to be quite a lot of individual variation.
. Also the pink at the mandible edge which is also mentioned as a separating point, is not fully reliable as individuals in both species can show it , though the one more frequently than the other . But look here:
So what do you think of this bird :