The population biology of buttefly release

[Chris J. Durden]

At 01:16  15/05/00 -0700, you wrote:
>Bruce and others,
>
>    The measure you propose is a good broad-stroke measure of genetic
>differentiation over space. Low Fst species are plausible candidates for
>release. But don't set the bar too low. Local populations of smallish size or
>unknown genetic structure might make relatively little contribution to the
>species Fst and yet be worth preserving intact for all of worries 1
through 4.
>    Would you release mainland North American Red Admirals (_Vanessa
atalanta_)
>in Hawaii? Presumably not since they are not native there, and the native
>Hawaiian species (_Vanessa tameamea_ one of only two native butterflies!) is
>fully reproductively isolated from the Red Admiral. Or is it? And even if
it is
>now, was it always? This is an extreme case, but consider that there are four
>species of _Vanessa_ in North America that arose despite the famous wandering
>tendencies of the clan and a presumably low Fst. Either this happened despite
>constant migration (supporting some level of uncontrolled release) or
geographic
>isolation (or at least attenuation of gene flow) was required. We don't
know! 
- - - -
  I don't think we even really know if *Vanessa atalanta rubria* of North
America is conspecific with *V. atalanta atalanta* of Eurasia. In habitat
from Hudsonia to Huasteca, and from Cumbria to Marakesh they sure have the
feel of different species to my eye. Rearing tests should be done in
confinement before any releases are attempted. This may be too late
already, considering the several recent occurrences of *Aglais urticae* in
New England and upstate New York, and the number of aircraft flights per day.
......Chris Durden