Jill Dening asks about Nankeen Night Heron (Nycticorax caledonicus) roost
trees.
In a few years of wetland and waterbird inventory in northern Victoria
(Australia) I carried out with Andrew Corrick and others, I came across
several roost sites for these birds.
Along the Murray River on the NSW/Victorian border NNH typically utilised
Willow trees (Salix spp.). When such exotics were absent, River Redgums
(Eucalyptus camaldulensis) were used, especially saplings with dense clumps
of leaves.
The species was found in large numbers in the redgum forests of Barmah and
Gunbower on the Murray River in the flood year of 1993, where 1000s bred in
the canopies of Redgum saplings (up to 5m), often away from open water.
Closer to home in suburban Melbourne, I have observed NNH roosting in dense
low vegetation on islands in the Royal Botanic Gardens. I have neved
observed them roosting in the White Mangoves (Avicennia marina) in Western
Port bay, se of Melbourne. This mangrove species is very low in structure
and may be difficult to access by these birds.
The only other exotic tree I have seen them utilising is Monterey pine
(Pinus radiata).
Martin O'Brien
Executive Scientific Officer
Scientific Advisory Committee
Department of Natural Resources and Environment
4/250 Victoria Pde.,
East Melbourne, 3002
Australia
tel: +61 3 9412 4567
fax: +61 3 9412 4586
e-mail:
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