G'Day again
On our recent trip to the Stzelecki desert (see earlier report), Pat and
I spent three days searching for Eyrean Grasswrens in far north western
New South Wales, from Cameron Corner to Fort Grey and south to Lake
Stewart and to Hawker Gate, however we could not find any suitable
habitat with Sand-hill Canegrass (Zygochloa paradoxa) in the area and no
grasswrens were located.
There are some sand dunes with apparent potential near Cameron Cnr
(triodia immediately east of the gate), and to the south, others with
reasonable drifts near White Catch? Gate House and others on the Fort
Grey road and also near Lake Stewart but Zygochloa paradoxa which may be
a prerequisite for Eyrean Grasswren habitat appears to be absent on the
NSW side of the border.
This canegrass is a conspicuous perennial plant with a distinctive
glaucous and bushy appearance normally growing near large sand drifts.
According to J.M. Black (Flora of SA) it occurs in all mainland states
except WA. So what has happened to sand-hill canegrass in this
area? Does it occur in far north western NSW? Its possible that we
missed it as vehicle access is restricted and walking in these vast
areas limits how much can be covered. However we did have a reasonably
good look anyway, investigating sites we could see with most potential.
It occurs close by in SA and the geomorphology east of the border looks
similar.
Sand-hill Canegrass is a hardy species that remains even in heavily
grazed areas with a history of rabbits, sheep, cattle and drought. In
SA, it is widespread where sheep and kangaroos are common but
interestingly, Eyrean Grasswrens are rarely recorded inside the dog
fence. There are a few sites north of Maree on Muloorina station where
Grasswrens occur inside the fence but they are hard to find there.
Is it possible that canegrass could be affected by heavy grazing
pressure from Kangaroos? I'm not sure if they eat canegrass but I think
they probably would graze on regenerating and juvenile plants. At
present there is an exceptionally large Kangaroo population east of the
dog fence and the total ground surface in the area shows signs of
disturbance from them.
Travelling south from Cameron Corner, the Kangaroo population must be
seen to be believed. They tend to move into the prevailing wind and
are massing up against the border fence in numbers difficult to
describe. There are many thousands of Red Kangaroos, possibly tens of
thousands, and also many Emu on the eastern side of the fence. The
landscape is literally moving with them but is contrasted by few animals
on the western side where these animals are naturally controlled by
dingoes. Because such large numbers of animals are present, it is
probable that we will witness an extremely severe ecological crash in
the area when the next drought sets in.
Ian May
PO Box 666
Enfield Plaza SA 5085
Tel: 0409 474 575
(08) 8380 9553
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