Invader of a different form

We recently came across this interesting lichen invader while walking at Garry Point park in Steveston. It was identified by a friend, who knows his lichens well, as the introduced and invasive orange wall lichen (Xanthoria parietina), also known as the golden shield lichen or the maritime sunburst lichen. This is a species that is becoming more common in southwestern BC, and grows only on sites with high nitrogen levels -- such as we get from automobile pollution -- and is known to be pollution tolerant. At Garry Point there is a population growing on the planted deciduous ornamental trees growing around the fish and chip shop. Bright orange-yellow, it's hard to miss them. These ones were growing within the reach of salt spray from the nearby ocean waters, so are tolerant of somewhat harsher conditions than many species of plants. Looking up the distribution in BC, the sunburst lichen is reported from Vancouver, Richmond, West Vancouver, Galiano Island, Agassiz and the Chilliwack area, and is probably present in other areas too. Given that most of us don't know the lichens, and that identification often requires use of a microscope and familiarity with the overall lichen flora, I have to wonder just how widespread it might be--and what other invading lichens might be around.