Wear shoes when
wading in Lake Maquarie
By Dr Mike Heasman & Gavin Ayre.
(excerpted from Ocean
Spirit Magazine)
It is always sensible to wear shoes when wading in the water
due to the risk of lacerations from broken glass or other sharp
objects.
Trailer yachties visiting
Lake Macquarie should be aware that there is currently a relative
abundance of medium to large razor clams in the shallows.
Razor clams, also called
“razor fish”, Pinna bicolor are large,
fan-shaped bivalves that live buried in the sediment on the
sea floor.
They are well known in
South Australia & Western Australia. In Lake Macquarie they
are virtually unknown among the boating public, and that is
potentially a problem. I have been sailing on Lake Macquarie
for over 20 years and have never heard of them being found here
previously.
Razor clams bury themselves
in sediment, leaving the top few centimetres exposed.
The
shell on the left is 400mm in length.
The razor clam buries itself
vertically in the sediment with a few centimetres of the shell
protruding. This leaves a very thin & sharp blade of shell
exposed for the unwary to stand on. So far I have only observed
them buried in weed beds, and this makes them even more difficult
to see.
I was so concerned at their
apparently recent arrival that I contacted NSW Fisheries. Dr
Mike Heasman of the Port Stephens Fisheries Centre at Taylor’s
Beach assured me that the razor clams are very much an endemic
species, definitely not a recent unwelcome arrival. In fact
this species, P.bicolor is found in usually low abundance from
NSW, Qld and through to the NT.
The recent appearance of
large numbers of adult razor clams is most likely the result
of an exceptional rate of survival of razor clam larvae three
to four years ago. Thus it seems that the population of razor
clams is likely to fall again, unless favourable conditions
return.
So the next time you are
sailing here on Lake Macquarie don’t be alarmed –
just wear shoes when you are wading
in the water.
The author would like to
thank Dr Mike Heasman of NSW Fisheries for his assistance. Photo
courtesy Gavin Ayre/
Sailaway