Male & Female Wallace's Hawk-Eagle? Sarawak, Malaysian Borneo (1 Viewer)

[dixonlau]

Location: Sarawak, Malaysian Borneo
Date: October 2022



Sorry for poor quality. They were too far away. Are these individual adult male and female Wallace's Hawk-Eagle?

Thanks.

 

[Andy Adcock]

Hadn't realised how similar Blythe's and Wallace's were but I think you're right based on the extent of rufous on the neck.

Tail pattern on the male also helps support ID as Wallace's.

 

[Andy Adcock]

Must admit, that tail is confusing me a bit now but not sure these birds are well illustrated in either of the books I've looked at?

 

[dixonlau]

I upload additional photos for better view id. Labeled Bird #1 (lighter color), Bird #2 (darker color).



Also there is nest nearby. Pls let me know if nest photo is allowed to post here or not. If ok, I will upload later. There are not chicks in the nest based on my observation (no feeding).

Bird #2 perched on nest edge and eating some prey. Not seeing any action of passing or sharing with Bird #1. In addition, after finished eating, both perched on branches nearby the nest. After a while, the Bird #1 perch on nest edge, looked into it for a while, then it picked up the carcass leftover by Bird #2 then flew off with it.

Bird #1

Bird #2

 

[Butty]

It's always best to post all the worthwhile photos right at the start. Saves everybody time 👍🏼
Unfortunately there is no full guidance on whether/which nest photos are acceptable.

 

[Andy Adcock]

On tail pattern I'd now say Blythe's.

 

[dixonlau]

On tail pattern I'd now say Blythe's.

Based on my cross check of Blyth's on (https://singaporebirds.com/species/blyths-hawk-eagle/ Blyth’s Hawk-Eagle), I believe the under body parts suggested is not Blyth's, correct me if I get it wrong. Though I'm not so sure of the tail pattern you've mentioned as I yet found clear info of it.

I'm also not sure Bird #1 is adult female or it is still immature/juvenile.

 

[dixonlau]

It's always best to post all the worthwhile photos right at the start. Saves everybody time 👍🏼
Unfortunately there is no full guidance on whether/which nest photos are acceptable.

Thanks Butty, noted. I decided not to post the nest photos as Wallace's is listed as vulnerable (https://www.mybis.gov.my/sp/52405 Nisaetus nanus), unless it can be use for better identification.

 

[James Eaton]

The tail pattern clearly indicates they are Wallace's Hawk Eagles (broad pale band on the uppertail is buff-tinged, on Blyth's it would be grey-tinged - no other fail-safe feature to separate them, that I know of in immature plumage).
You have a clear adult on the left, judging by the dark breast streaking - this would be absent in young birds. The right hand bird could be an immature.
Note however, Wallace's Hawk Eagle in Borneo appear to be highly variable in adult plumage - birds in mainland Southeast Asia and Sumatra are generally much darker, particularly on the underpart streaking. You can have adults in Borneo lacking any dark streaking.

As for them being a pair - did you notice a size difference between the two? Females are much larger than males.

James

 

[dixonlau]

Thank you all for the feedback. Went back to check on them again today and confirmed Bird #1 (lighter color one/Right side bird) is female as saw it sitting on the nest in early morning when weather still cooling. No male sighted during that time. After quite sometime, Bird #1 (female) flew off and short while it came back but not sit on the nest.

After longer time observed, male also returned. Both off and back then finally saw Bird #1 (female) sit on the nest, only about to sit and it stood up again because alerted by male returned and perched nearby branches.

And thank you @James Eaton for pointing out some clear features for better identification.

 

[dixonlau]

On tail pattern I'd now say Blythe's.

Thank you Andy for the effort to help find the id. Appreciated.