I visited Bahri sewage pools again today with Marwa to ring some weavers. For the first time we noticed a small group of Cinnamon Weavers near to the Northern Masked Weaver colony we have been netting at recently. It was nice to see them, but it does mean that it will be much more difficult to know what I am catching now, as the females seem to be almost identical and one of my main aims is to find a way to separate the two. So far my concerns have been about the identification of the females and non-breeding males, but today we caught a bird that threw another spanner in the works, as it seems to be a male that is intermediate between the two species. I wonder if it might be a hybrid - a distinct possibility given the similarity of the females, the almost identical nesting behaviour, and the presence of both species breeding together at one site (I assume the Cinnamon weavers are breeding nearby, as they were in breeding plumage).
Note that the bird is moulting out of its non-breeding (basic) plumage, which is why it still has some pale brown feathers on the head and whitish feathers on the underparts. This is nothing to do with it being a probable hybrid.
I have included some photos of male Northern Masked Weavers in breeding plumage below for comparison. Although the cinnamon colouring around the head and on the breast is quite variable, I have never seen anything close to the bird caught today.
From the photos above you can see that the hybrid has a lot more chestnut on the crown and underparts than the Northern Masked Weavers. It also has a bit more black on the crown than most Northern Masked, but less than most Cinnamons (see below), though the extent of black on the head of Cinnamon Weavers varies a lot, from little more than a face patch to almost a complete hood. The photos above show that the upperparts of the hybrid are much more like Northern Masked, being bright yellow rather than golden, though it does have a couple of the golden feathers (for example on the coverts of the open wing shot) that are more typical of Cinnamon.
This hybrid individual (I will assume this is a hybrid unless good evidence arrises to prove otherwise) is very similar to photos I have seen of Yellow-backed (or Black-headed) Weaver Ploceus melanocephalus. In particular, the yellow nape and upper parts contrasting with dark head and cinnamon underparts is quite distinctive. The main difference is that this hybrid bird has a black and cinnamon head, while Yellow-backed Weavers have an all black head. This species is found in South Sudan and in Eritrea and Ethiopia up to the Sudan border. Potential hybrids will clearly have to be considered when identifying birds in any of these areas, where all three species could occur.
Note that the bird is moulting out of its non-breeding (basic) plumage, which is why it still has some pale brown feathers on the head and whitish feathers on the underparts. This is nothing to do with it being a probable hybrid.
Probable Cinnamon x Northern Masked Weaver hybrid, Bahri Sewage Pools 4th April 2014
Probable Cinnamon x Northern Masked Weaver hybrid, Bahri Sewage Pools 4th April 2014
Probable Cinnamon x Northern Masked Weaver hybrid, Bahri Sewage Pools 4th April 2014
Probable Cinnamon x Northern Masked Weaver hybrid, Bahri Sewage Pools 4th April 2014
I have included some photos of male Northern Masked Weavers in breeding plumage below for comparison. Although the cinnamon colouring around the head and on the breast is quite variable, I have never seen anything close to the bird caught today.
Northern Masked Weaver
Northern Masked Weaver
Northern Masked Weaver
Northern Masked Weaver
Cinnamon Weaver
Cinnamon Weaver
Cinnamon Weaver
Cinnamon Weaver
This hybrid individual (I will assume this is a hybrid unless good evidence arrises to prove otherwise) is very similar to photos I have seen of Yellow-backed (or Black-headed) Weaver Ploceus melanocephalus. In particular, the yellow nape and upper parts contrasting with dark head and cinnamon underparts is quite distinctive. The main difference is that this hybrid bird has a black and cinnamon head, while Yellow-backed Weavers have an all black head. This species is found in South Sudan and in Eritrea and Ethiopia up to the Sudan border. Potential hybrids will clearly have to be considered when identifying birds in any of these areas, where all three species could occur.
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