migration

[Jean-Michel MAES]

A little bit far of the discussed point... So many topics about monarch and
monarch populations...

I understand that monarch (Danaus plexippus) have migrations from Mexico to
Canada and back or from Canada to Mexico and back. Why do they migrate ?

In Nicaragua we have also Danaus plexippus, another population or subspecies
if i am not wrong. Why do they not migrate ?

Sincerely,

Jean-Michel MAES
MUSEO ENTOMOLOGICO
AP 527
LEON
NICARAGUA
tel 505-3116586
jmmaes at ibw.com.ni
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