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| Red& Blue Damsels laying eggs, Webbs Dam, Mt
Clear area (L.Johnston) |
Happy New Year, lunar and solar! It has been a rather up and down
start to the year, with some bitter nights and the occasional summer day! In
many ways it has been a gentle summer … considering the day-length shift back to
short days is almost upon us (5th or 6th February) … and a wonderful one for
many plants and animals. After the pillaging of my greengage by the sulphur
crested vandals I have deep, dark thoughts of getting up a petition for their
capture, caging and export! And then there is the St John’s Wort!
Your Results
Most results were well within the usual range of readings for
this time of year, even the dissolved oxygen readings don’t look too bad. The
electrical conductivity in the creeks above the Molonglo Gorge was elevated but
not as high as it can be. The pH for the upper Queanbeyan was quite low, but may
reflect the on-going run-off in that catchment.
Several of you have reported blanket weed, which worries me a
little.
- Velvet moss (Vaucheria spp, a golden green
conspicuous alga) is usually densely intertwined, springs back on
compression and smells muddy or fishy. It’s not uncommon in upland streams
and where there may be a source of nitrogen.
- The silkweeds, Spirogyra and Zygnema
mainly, are usually very slippery and tend to form a veil in the water
rather than a blanket. They may range in colour from lemon-yellow to dark
bottle-green, but they don’t smell and they don’t knot-up like the branched
blanket-weeds. They are seasonal and flourish in sunny spots.
- The blanket-weeds are coarse to the touch, don’t have
much give and really do often smell of tomcat. They are perennial. They
indicate not only lack of cover but also high phosphate levels.
All of these conspicuous algae may be around especially where you
have unshaded waterways and snags or rocks for them to attach to. The blanket
weeds become a real problem when they start to choke flow. If you are not sure
what it is bring me a sample … a pinch in gladwrap will do nicely … and I’ll let
you know. In a season like this I’d be expecting plenty of silkweed!
More Frog News
I have done the sums and this spring was reasonably good for
rural and country town frogs but city dwelling frogs are still not exactly
flourishing! The
short version (
266KB) was also distributed with this newsletter; the long version, with the
numbers, will be in the CHiP report.
There are a couple of summer calling frogs that people would like
to know if they are actively about. Much of the time, especially since the fire,
these have been passed over, but Dr Hunter and Dr Osborne would like to know if
they are still here and where that might be.
The two frogs of interest are the Broad Palmed Frog (Litoria
latopalmata), a tree frog that spends much time on the ground and
Bibron’s Toadlet (Pseudophryne
bibroni), a small frog that may have disappeared from round here. The
broad palmed frog makes a rising series of duck-like quacks, and calls on summer
nights. It is supposed to be found in the Murrumbidgee and major tributaries. If
you hear it, try to record it and let Anke Maria know at
frogwatch at ginninderralandcare.org.au. The Toadlet may still be around in
the upper Jerrabomberra area or Carwoola … listen for a lonely but sharp ek
every now and then, over the top of the crickets and cicadas. Then it is the
same story, let Anke Maria know, and the information will reach the people who
want it. |
