That's a Red-rumped Swallow nest. Was this in Hong Kong? They are quite rare as breeding species here.
The sparrow was probably investigating potential nest sites. I think it's possible that it would take over a swallow nest if it thought it was suitable. Author: louislee Time: 6/06/2017 12:14
I saw in the photo description 嘉義 (Chiayi), which is a city in central Taiwan. Author: ssrg Time: 7/06/2017 01:24
In Hong Kong, both Tree Sparrow and Crested Myna will use House Swift nest.
And House swift will use Barn Swallow nest.
在香港,麻雀及八哥均會佔用小白腰雨燕的巢。
而小白腰雨燕則會佔用家燕的巢。
[ Last edited by ssrg at 7/06/2017 01:26 ]
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