Dear Syd, I think the issue here is that many people use a loose definition
of rainforest, embracing all sorts of wet forest including some dominated
by eucalypts, which would not be classed as rainforest by ecologists. Bell
Miners feed mainly on psyllids and their protective covers (lerps), which
are found on eucalypt foliage: the preferred genera are exclusively found
on particular groups of eucalypts. Bell Miners maintain psyllid
infestations by aggressively excluding other insectivorous birds: we have
shown that species such as pardalotes, rosellas and Striated Thornbills are
extremely effective at reducing psyllid numbers when the psyllids are not
defended by Bell Miners. Bell Miners do feed on other invertebrates and
nectar, but most if not all Bell Miner colonies rely on psyllids and lerps
as their main source of food. I've seen a new colony formed (and psyllid
populations subsequently increase) when Bell Miners were able to occupy it
by feeding initially on mistletoe nectar. Most Bell Miner colonies are in
damp forest or gullies with dense understorey, and the understorey may
consist of typical rainforest species. I wonder if the report you mention
could refer to a wet gully with rainforest shrubs, perhaps adjoining or
intermixed with true rainforest. If one of the rainforest species was
flowering, the Bell Miners might even be feeding on the nectar as a
temporary food source. But I'd be very surprised if there were not
eucalypts close by, which would form the core of the Bell Miner territory.
I do not know of any Bell Miner territory where psyllid-infested eucalypts
did not form the main long-term food source, and would be interested to
hear of any exceptions. Hope this helps, Richard.
Richard Loyn
Arthur Rylah Institute
Dept. Natural Resources & Environment, Victoria.
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