Winter Damselflies
There are a lot of comments around at the moment by people
noticing that some birds seem to think winter is over already for this year!
Various species from thornbills to ravens have been seen collecting nesting
material, and several species of cuckoos have been heard calling, both here in
Canberra and elsewhere, quite unseasonally, suggesting they think the birds
whose nests they parasitise might also be active, or nearly so.
And it’s true that for mid-July we have had relatively few
severe frosts or particularly low sub-zero temperatures. It seems the dragonflies
and damselflies have also picked up on this.
It was a slower wind-down to the dragonfly season this year,
in my view, with several species persisting for longer than I would expect them
to. Wandering Ringtails (Austrolestes leda), and even a few Inland
Ringtails (Austrolestes aridus) which seem to be rather itinerant here
in Canberra but had a relatively good season this year, were being found well
into May, and even June. Not only by me, but by number of people submitting
their photographic records to Canberra Nature Map (CNM). Tau Emeralds (Hemicordulia
tau) also seemed to persist, admittedly in relatively small numbers, longer
than I am used to, with one reported as late as 14 June.
And yesterday (17 July), a record came in to CNM from Shorty,
aka ‘rawshorty’, of a Wandering Ringtail on Mount Ainslie saddle. What’s more
it was a teneral male, meaning it was only recently emerged from its watery
larval home (presumably a small dam in the Mount Ainslie Nature Reserve) and
was not yet fully coloured-up, and was munching into what looked like a small
water beetle or some such.
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| A teneral Wandering Ringtail (male) photographed by Shorty on Mount Ainslie. |
It is known that in some places (that have a distinct winter
that precludes pretty much all dragonfly activity) Wandering Ringtails may ‘over-winter’,
which is not a usual behaviour of damselflies. But I never expected this would occur
in Canberra which really does get very cold! I had made some half-hearted
efforts in previous years to see if I could find any overwintering individuals,
but had never been successful. So, when Shorty’s image showed up I thought it
time to have another look.
I rationalised to myself that the best bet would probably be
a small, well vegetated swamp with a northerly aspect which would allow any
sunshine to warm the shallow waters quickly. So I decided to check out a tiny
seepage swamp on the northern flanks of Black Mountain, just off Belconnen Way,
where I know Wandering Ringtails can be abundant when the summer conditions are
favourable. I had recorded a late emergence event of this species there on 14
May (32 individuals including seven mating pairs) and assumed they would be the
last for the 2019-20 season.
When I arrived, the sunshine was weakly obscured by a haze
of high cloud, there was a slight breeze, and it was a balmy 12.5°C (it had got
down to a relatively mild 0.2°C overnight). It all looked very quiet except for
the four cockies and four Wood Ducks and I spent a good 15 minutes scrutinising
the sedges for any perched damselflies. But then, just as I was about to leave
and was doing one final scan with the binoculars – there it was. A male
Wandering Ringtail. All by itself, not moving but being gently buffeted by the
breeze and presumably trying to soak up as much warmth as was possible. I
clicked away, even the 400 mm lens finding the distance difficult, but any
attempt to get closer would mean approaching it from the other side of the
swamp and directly into the low-angled sun. But I had my proof and felt quite chuffed.
And it really hadn’t been that difficult.
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| An adult male Wandering Ringtail at a tiny swamp on the northern flanks of Black Mountain in mid-July |
I went and checked out the nearby small dam, largely shaded
by trees, and as expected found no activity there at all. Returning to the
swamp, I went to take just a few more photos, but the damselfly had moved on. I
eventually relocated it about 2 metres away, and in a clump of sedge right on
the edge of the opposite bank. I worked my way around slowly and what I hoped
was unobtrusively until close enough to crouch down and use the little Lumix
camera on macro, getting near enough to largely overcome the poor lighting
direction. When my closeness did eventually disturb it, it fluttered weakly just
20 cm away and re-perched. Poor thing, I thought, not even warm enough to be
able to fly properly.
It wasn’t until I got home and downloaded the photos that I
realised the macro shots were of an individual with a malformed wing-tip, and
obviously different to the individual I first photographed with the long lens.
So – at least two males were present on this tiny swamp in mid-July. There’s no
way to know if they were survivors of the emergence I recorded two months previously
in mid-May, or had emerged much more recently, like Shorty’s male on Mount
Ainslie, but it is clear that, at least this year, this incredibly hardy little
species (they are only about 35-40 mm long and incredibly slender) can survive a
Canberra winter!
