butterfly attraction

[David R. Britton]

In article <199711180832.IAA18185 at redpo>, andrewd at REDAC.CO.UK wrote:

> >
> > In article <34704427.42EA at gate.net>, viceroy at GATE.NET wrote:
> >
> > >
> > > Alas, the introduced plants are often hosts for local butterflies, and
> > > can cause problems by artificially elevating populations, which are then
> > > regarded as pests.
> >
> > Yep, I guess we have one of those in Northern Queensland (a beautiful
> > lycaenid) which chews up people's prize cultivated orchids.
> >
>
> Things can happen the other way too. I remember some mailings back earlier in
> the year where the European Garlic Mustard was out competing the native USA
> species.  This plant was more attractive to the butterfly P. virginiensis
> which would ignore it's natural food plant and lay eggs on this instead.
> Unfortunately the toxins in the European Garlic Mustard was too strong for
> the caterpillars and they would die.  This I gather would wipe out a colony
> of P. virginiensis quite quickly.

Similar to what is happening with the Richmond Birdwing (Ornithoptera
richmondia) in southern Qld.; it lays its eggs on the ornamental
(introduced) Dutchman's pipe instead of the native Aristolochia vine; the
larvae cannot develop on the introduced Aristolochia.  Fortuntately there
is a movement to encourage schoolkids and others to plant the native vine
in their gardens to try and establish urban populations of this
butterfly.  I think (don't have the publications in front of me to verify
this) that it was mechanical differences b/n the plant species rather than
chemical ones.

Dave.

--
David R. Britton, Biological Sciences, University of Wollongong
Wollongong, NSW, Australia, 2522.
Ph.(61-2) 4221 3436,Fax.(61-2) 4221 4135