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Michael Norris wrote:
"An increase in pigeons is no more
valuable
ecologically than an increase in Common Mynas"
I found Michael's comparison of frugivorous
pigeons with Common Mynas quite disturbing. Unlike Common Mynas, which are
introduced pests, the pigeons that he refers to are native species.
Furthermore, two of the species that regularly consume camphor laurel fruits,
Wompoo and Rose-crowned Fruit-doves, are listed as vulnerable under
the NSW TSC Act. Surely, an increase in the numbers of either of these
species would be of considerable ecological value.
By equating the ecological value of
frugivorous pigeons with that of Common Mynas, Michael overlooks the
important and well-documented role that these pigeons play as seed
dispersers in Australian subtropical rainforests. Given that over 70% of
the tree species in these forests are adapted for seed dispersal by vertebrate
frugivores, I believe there are compelling reasons for maintaining and, where
necessary, enhancing avian seed disperser populations.
The proliferation of camphor laurel and, to a
lesser extent, privet in abandoned pasture in northern NSW, may go some way
towards compensating for the destruction of almost all the lowland subtropical
rainforest that took place in the late 19th century.
Any increases in frugivore populations that are
associated with the spread of these weeds should, in my view, be seen as part of
the recovery of frugivore populations in this region.
Getting back to the topic raised by Carol
Probets. The camphor laurel/avian sterility
issue has been flogged to death in northern NSW, and as John McLaren pointed
out, the research supposedly supporting the theory has been largely discredited.
Over the past 5 years, I've observed 19 bird
species feeding on camphor laurel fruits and 12 species feeding on the fruits of large-leaved privet. The
thousands of Topknot Pigeons, White-headed pigeons and Figbirds that return to
the camphor laurel forests to feed on their fruits year after year simply
do not bear the sterility theory out.
Regards
Damian Hackett
Rosebank, NSW
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