Whilst birding the Jubail area in late-June I came across an Upcher’s Warbler. This was a very unusual sight as the birds are passage migrants in the Eastern Province as far as we are aware. I have seen birds in the summer months in the west of the Kingdom but never in the east. The main identification points to separate Upcher’s Warbler and Eastern Olivceous Warbler are that Upcher’s Warbler is generally bigger and has a stockier appearance although this can be difficult to judge on a lone bird if unfamiliar with them. Wings, legs, tail and bill are all longer on Upcher’s Warbler than on Eastern Olivaceous Warbler with the legs and bill being thicker on Upcher’s Warbler. The tail on Upcher’s Warbler is long and ‘full’ and darkens towards the tip, which is not the case in Eastern Olivaceous Warbler. This darkening of the tail can be seen in the below photographs. The tail is also moved in a rather lazy swinging motion often sideways and also upwards and is also fanned, which is not often if ever shown by Eastern Olivaceous Warbler. The exaggerated tail movements of Upcher’s Warbler are often the first thing that draws attention to the species, especially if they are deep in cover. This bird did not move its tail like this and just did a single downwards movement that is similar to Eastern Olivaceous Warbler. Unfortunately, the bird did not stay on the open for very long and good views could not be obtained.
