Journal of the Royal Society of New Zealand abstracts
Distribution and conservation status of the dwarf inanga Galaxias
gracilis (Teleostei: Galaxiidae) an endemic fish of Northland
dune lakes
D. K. Rowe, B. L. Chisnall*
Surveys of 27 Northland lakes revealed two new locations for
Galaxias
gracilis but confirmed its restricted geographical distribution. It is now
present in 11 lakes on the west coast of the North Island within 50 km of
Dargaville, and in Lake Ototoa on the South Kaipara Head, where it was
introduced in 1986. Densities of
G. gracilis were determined by
nocturnal fyke netting in the littoral zone of the North Kaipara lakes. It was
abundant in two of these lakes, common in two, rare in five, and extinct or
close to it in at least three others. We conclude that
G. gracilis has
one of the most restricted geographical distributions of any New Zealand native
fish, and that its densities have declined in over 80% of the lakes from which
it has been recorded. Although trout predation could account for the current
low density of
G. gracilis in three lakes, it is not responsible for low
densities in six others. Factors responsible for the decline of this species
are therefore unknown, so it is a threatened species in terms of its
conservation status.
Keywords: Galaxias gracilis, threatened fish, Northland lakes, fish
surveys, Galaxiidae, trout predation
(c) Journal of The Royal Society of New Zealand,
Volume 27, Number 2, June 1997, pp 223-233
PDF file of entire paper: medium quality (761K); (scanned from paper original: notes about this process)
This year's abstracts |
Journal home page |
All abstracts |
Publishing home page