Lesions and ticks on birds

[Sylvia and Mick]

Having read an article on lesions on birds in October issue of Bird Watching just thought I would post this pic of a hedge sparrow taken at the end of the Zinc Works road which appears to have some sort of lesion on the face.  Also have noticed and photographed birds of late which appear to have ticks as the Robin and Shore Lark attached also.  Do ticks kill birds and could this be a reason for not seeming to see so many small birds these days.