Certainly this year there are lots of Grey Fantails passing
through Bayside although we haven't recorded them in the same
densities as in one - probably aberrant - day in April 1998 .
However, from old published records they were more numerous in
this area in the 1950s and 1970s outside the peak migration
months of April and October.
So two questions arise. Why are they now less frequent outside
the migration periods and why are there lots on migration now ?.
Of course there will be multiple reasons for both phenomena.
But my current best guesses is that we have lost them outside
the migration season mainly because of the devastating effects
of "campaigns" of pesticide use to clear the introduced
Argentine Ant from this area in the early 1970s (which may also
have cleared most of our small bat population and have been
responsible for clusters of lethal cancers amongst humans).
Dieldrin etc. are long-lived in the ecosystem.
Similarly the current migration peaks may not be a sign of
improved ecology but of degradation. Fantails are insect-eaters
and may be being pushed towards coastal regions because of a
lack of food in other areas, partly because of the impact of the
run of dry weather (nothing of course we cheerfully say due to
the global warming resulting from the activities of the tiny
minority of the human population in the USA and Australia which
eats oxygen faster than any other ultrataxon).
"Every silver lining has a cloud"
Michael Norris
Bayside, Victoria
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