I just found that Aubrey's Miscellanea has been published on the web a year earlier than scheduled by the Project Gutemberg team.
Here is at the paragraph that mentions the Wren Hunt:
Near the same place, a party of the Protestants had been surprized sleeping by the Popish Irish, were it not for several wrens that just wakened them by dancing and pecking on the drums as the enemy were approaching. For this reason the wild Irish mortally hate these birds, to this day, calling them the Devil's servants, and killing them wherever they catch them; they teach their Children to thrust them full of thorns: you will see sometimes on holidays, a whole parish running like mad men from hedge to hedge a wren-hunting.
The book is concluded with the place and writing and the date "Eston Pierse, April 28, 1670", which brings it forward 20 years from the date of publishing (1690).
It can also be seen that the "Manx Legend" quoted in the DT probably ultimately arises from this quotation, as this is (so far) by far the earliest written reference to Wren Hunting.