The only Treecreeper to be resident in the area, we thankfully don't have the difficulty of distinguishing it from its close relative, the Eurasian Treecreeper, from which it is usually told apart only by the distinct white spots at the end of the primaries, though, just to be difficult, these can be absent. There are various photos in this gallery that show these white spots well, but it's not that easy in the field. Another diagnostic is a longer bill than the Euarasian, though as the latter's can be variable this isn't much to go on.
Quite often found in loose family gatherings Short-toed Treecreepers are rather like a small mouse scurrying up the trunk of a tree - as opposed to the Eurasian Nuthatch, which usually descends tree-trunks. Call is a rapid, high pitched, "Teet teet, teet", akin to a Tit on steroids. Seemingly unafraid, unwary and uninterested in Man, I have had them land on me when I have been standing still, and have heard similar stories from others.
Happily we are seeing a marked increase in numbers of this species throughout Portugal this century.
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