ID: Hume´s Leaf Warbler // Blekbrynsanger

Hume´s Leaf Warbler at Yttersand, Flakstad, Lofoten 31. October

To find a Hume´s Leaf Warbler was a dream come true. I have dreamt of this small jewel from the east many autumns, and it felt so far-fetched to actually find one. It is over 30 records of this species in Norway, so it is not one of the biggest raritys i have found. But still. It was so pure and beautiful this October day.

I guess there are many out there dreaming of finding their very own Hume´s Leaf Warbler, or just trying to get a glimpse of one. Therefore i was thinking i could make an ID-piece on this blog. Especially since we got some good audio of the call as well, which is a important piece of the puzzle of Hume´s Leaf Warbler. So here we go!

Hume´s Leaf Warbler call (recorded by Jon Olav Larsen the day after we found it)

This sound was important for us when finding the bird. As soon as we got out of the car at Yttersand we heard this call. As noone of us had experience with Hume´s Leaf Warbler before we all just had our eyes wide open, looking at eachother - wondering at what bird this might be.

When we saw what we had in front of us, it all became quite clear. This was not a Yellow-browed Warbler (now reffered as YBW), as i have heard so many times before - this was something else. If it was a YBW we would have pinpointed the call at once. We have all heard it several times before, and know the call very well. But with this bird - this was not case. YBW was not even in our thoughts when we heard the call!

After a while when we were with the bird, I heard the similiaritys with the YBW-sound, but there are some obvious differences as well. As the call of the YBW is like a bird on speed, this sound was much more compact and also the last part of the call goes down, instead of up like the YWB. Below is a link to the call of YWB uploaded on Xeno-canto.org. Check out the differences yourself!
The Hume´s Leaf Warbler is also said to have an other sound, more resembling the Chiffchaff.

Call of Yellow-Browed Warbler from Xeno-canto.org

 

The bird was fantastic. It was a low autumn sun outside and around zero degrees, but the bird was very active catching flies and showing quite well.

This picture is not in neutral light it can therefore show some details who are not considered as pro Hume´s characters, but still we can focus on some important details for Hume´s Leaf Warbler:

• Only one visible wing-bar, and it is more "dull" and shorter than on YBW.
• No visible yellow in supercilium (despite the sunlight)
• Earcovers are less marbled than on YBW
• The colours on the birds are dull and pale (again despite the sunlight)
• The head and nape more grey, the nape in contrast to the mantle.
• The dark areas of the wing-covers and tertials are more grey than black, making less contrast in the plumage than to be found in YBW
• Grey-buffish flank´s
• Dark legs

I was expecting the Hume´s Leaf Warbler to have a darker lower mandible, but on pictures on the internet for Hume´s Leaf Warbler this variates and on this picture the sunlight makes it even more brighter.

So, to clinch a Hume`s Leaf Warbler you have to establish a set of ID-characters from the birds itself, but the call is also important as there are pale Yellow-Browed Warblers out there who can show some of the same characters. Good luck!

Hope you enjoy the blog. Please comment or send us an e-mail if there is anything we can help you with.

-Håvard