Honshu White Admirals

[Nigel Milius]

Apparently introduced into the Karangahake Gorge in 2014 in an attempt to help control Japanese Honeysuvkle, I saw 2 in in Tairua and 1 in Cooks Beach on 28th February. These are the first I've seen up here, so presumably their range is expanding as was hoped. Given the history of introduced species in NZ, I'm quite surprised things like this are still happening, but I'm no expert on the matter and perhaps someone with more knowledge can explain why/if this was a sensible move. Quite pretty though!

[David Riddell]

Introductions of biological control agents are still occurring, though they are a lot more regulated than in the old days (e.g. mustelids to control rabbits). There are, for example recent introductions of beetles to control alligator weed and tradescantia. It seems Honshu white admirals are quite host-specific, only very rarely laying eggs on species other than Japanese honeysuckle (those all being exotics) and most unlikely to attack any indigenous species. They're also, as you say, a lot prettier than most biocontrol agents! Some info here:
https://www.epa.govt.nz/assets/FileAPI/ ... n-Form.pdf
According to Landcare Research white admirals have been recorded in Tairua, though Cook's Beach looks like a range extension. Checking iNaturalistNZ there are also some very recent records (since November) well to the west and south of Karangahake (the only place I've seen them), including Ohinewai, Morrinsville and Tauranga. There are also a couple of records around Murupara from 2020. Given the amount of Japanese honeysuckle we have around here (about 20km west of Morrinsville) I'd be very happy to see them spread further.

[Davidthomas]

They're regular on my Parents farm now just on the eastern side of Morrinsville. And i've seen them also in Te Aroha regularly around Howarth Memorial Wetlands