Thanks to Steve
Holliday, Barbara Slotemaker de Bruine, and Tom Green.
It appears that the weed in question is Vallisneria gigantea (synonym:
spiralis), a native. Plants of the genus are widely used in aquaria and
known variously as eelweed, eelgrass, wild celery and tapegrass. It is
listed both as a food for waterfowl and a pest in channels and waterways.
Barbara once worked on clearing it from LBG. Its evident suitability as a
food for waterfowl might have been the reason for its planting at Tidbinbilla,
although whether it was planted or arrived in the ponds naturally I do not
know.
From: Geoffrey Dabb [
Sent: Saturday, May 27, 2006 4:48
PM
To:
Subject: FW: [canberrabirds]
Water-weed?
Peter Fullagar and I have been discussing
a water-‘weed’ on which a pair of swans at Tidbinbilla are feeding
their cygnets. This grows up to at least 60cms below the surface and is
well-suited to the swans’ feeding technique. When brought to the
surface by the adults it is attacked voraciously by the cygnets, sometimes
being. first ‘washed’ by the adult, presumably to remove soil from
the roots. Further comments below. Can anyone help with ID of this
particular plant – or on whether it was artificially planted
there? Geoffrey
