Sunday, 30 November 2014

Night bird antics

A few years back it was conventional wisdom that Powerful Owls only existed in the Canberra area in the Brindabellas.  Then a bird of this species was found in the Australian National Botanic Gardens by a group on a beginners bird walk - fortunately led by an expert who recognised the bird and alerted many others.  Many folk (at least 400) flocked to the Gardens to see it.

A year or more later another bird (of course, possibly the same one) was seen in the Rainforest Gully of the gardens.  Again many people went to see it.

On 27 November 2014 a very alert COG member looked up after noticing a guano patch on a bike path past the North Canberra Bowling Club.  There was a Powerful Owl sitting high in a very tall tree.  It has been seen by many people in the following days.  I joined that number this morning.

My first view was from the back ...
 ... and then by stepping into Haig Park the front.
I have clipped the following image from the preceding one to reveal the talons.  This also shows that the bird isn't holding prey this morning.
Hopefully the following description is enough of a warning for any sensitive souls that the link in the next sentence is nature red in beak and claw.  An expert COG member has posted most excellent video of the bird coughing up a pellet and then feeding on a Ring-tailed Possum.

I have not seen this species in the vicinity of Carwoola but have heard one once.  Their call is distinctive.

Also on the night-bird front, our Tawny Frogmouths have been off on tour for a few days but were located yesterday on a roost used for the first time this year by the female during the brooding period .
This is the first time I have seen the chicks split themselves between parents.  They usually stick close to Dad during the day.

They returned to this roost 3 days later, adopting a more customary arrangement.  The arrows are added by me to highlight where the birds are, not indications of Jovian vengeance. 
At least one of the chicks is trying a camouflage pose: he didn't hold it for very long!

Thursday, 27 November 2014

Where do Koels come from?

Anyone that has answered "Eggs" should report to the Headmaster's Study after the lesson!

This post has been stimulated by a couple of soundings of (what is called this month) Australian Koels.  The first was in Orange on our recent trip and the second in our front yard in Carwoola.

The latter observation was the second, in 8 years, on our property although the species has been reported somewhere in the Carwoola area in 6 of the 8 years.  Reports have tended to be in November or December.  Perhaps it is significant that we are 200m higher than Canberra and our plums are still way off ripe.

When I reported my latest sighting to the COG chatline a member commented that they regard Koels as an urban bird, including country towns such as Cowra and Goulburn.  He noted that there could be plenty of fruit - do Koels eat strawberries? - in a rural residential area like Carwoola to bring them in.  (They might also be aware - by whatever means Koels are aware of anything - that Noisy Friarbirds nest in this area, which a pair are doing in our yard as I write.)

I responded that a matter of interest to me is the route that the Koels travel to arrive in the Canberra Region.  Do they come from the North, travelling down the ranges, or from the South coast, perhaps coming up to the divide on the valleys (with the Shoalhaven being a strong candidate?  So I downloaded Koel data for NSW from ebird.  This gave me 1928 records.  (Note that I didn't do the separate selection for the ACT, because it is what happens before the birds get to that Territory that was of interest.)

What follows is pretty much of a mind game (or speculation) since I don't think there is enough data around to do the multi-dimensional analysis needed to try to tease out what is actually going on

A first point is to examine the frequency of reports.  I decided that month was a suitable time dimension.  As shown below they are very much a late Spring-Summer bird.
I then selected the latitude and Longitude of observations for the months of October (green icon) November (yellow icon) and December (red icon) and plotted them on Google Earth.
I shall deal with the letters A and B somewhat further below.

There are a mixture of red, yellow and green icons right down the Coast, rather than as i had hoped green icons (October) predominantly in the North and red ones (December) dominating in the South.   I have extended the process to look at the location of reports for September, and for week in September rather than the month as a whole, but again there is no clear picture, other than fewer reports South of Sydney.

There also seemed to be variation between years in the number of eBird reports of Koel in September  (from zero in some years up to 20 in 2010 and 2012) but no significant variation between the distribution through the month.

The conclusion I come to thus far is that when the Koels head South they pretty much come in a rush, arriving at more or less the same date all down the Coast.  One must presume that there are available, at more or less the same time throughout this range:
  • fruit of various sorts for them to eat, and 
  • host nests in which to deposit their eggs. 
It is about 750km from Brisbane to Sydney (in a straight line).  I haven't been able to find an estimate of the flying speed of a Koel (of any species) but did find one estimate of the flying speed of a European Cuckoo as 50mph (~80kph).  Thus, as a massive approximation, it might take a migrating Koel 10 hours to fly that journey.  This is obviously a benefit of avoiding the road works on the Pacific Highway.  The relevance of this is that it seems possible that if a bunch of Koels leave their Wintering grounds at the same time in response to some trigger, the ones that get to Sydney might only be a day after those that find satisfaction at Byron Bay and the adventurous ones get to beautiful downtown Moruya (or even Mallacoota) a day later.

Returning to the letters A and B.  These mark the position of a couple of areas in which the eBird reports are  dominated by the month of December.  A is roughly speaking between Moree and Inverell while B is the Blue Mountains West to about Bathurst. Perhaps this demonstrates the arrival of a few bold exploring Koels who finished their business on the Coast and followed a few food source over the ranges?  If that is the case it could lend support to the view that the ACT Koels come from the Coast rather than following down the Ranges.

It is of course possible that the route has changed over time.  Perhaps the first few Koels got here from the Coast route but have learnt over the years to travel by a hypotenuse (again, at 80kph, they could make it from Brisbane to Canberra in a hard day's flight, not being seen by observers on the ground).

An email comment on the first published version of this post commented that
"The data available are insufficient, as you noted, to really be able to tease anything out. And if they do indeed make the flight south in a 'rush', i.e. within say a 12-hour window, then opportunistic observations by birdwatchers will never be able to tell us how they move (i.e. where they come from and by what route). Only some sort of tracking device would do that effectively."
So there is a nice little research project for someone!

ANPS goes a long way East!

Note: a number of clarifications and corrections have been made after comments.

Today the ANPS WW went a long way East to Tianjara Falls.  Those who felt like a bit of scrambling went a bit further East, as will be revealed.

On arriving at the junction of Touga Rd and Highway 92 we found that conservation, NSW style, was occurring.

If they are trying to improve fire prevention its a pity they didn't pick (or indeed, as I originally typo'd "lick") up this lot of rubber stuff.
Three snaps of Leptospermum sp.  This first one is yet to be identified to species.
The next two are L. rotundifolium

Pimelia linifolia
Mitrasacme polymorpha
Dampiera stricta
Thysanotus tuberosus
Then we moved about 20km further East to Tianjara Falls.  Despite the overall dryness there was still a little water coming over.
Lambertia formosa
Kunzea ambigua
Melaleuca thymifolia
Scaevola ramosissima.
Bossiaea ensata.
Xyris juncea
 Isopogon anethifolius
A naff snap, taken at about 150m range, of a possible Callistemon below the rim of the Falls.  I couldn't get a closer shot and theredidn't seem to be any growing in the Creek bed.
Actinotus helianthi
Isotoma axiallaris: it was found at the Eastern extremity of our walk after lunch.
Near the car a couple of  Cryptostylis subulata (tongue orchids) were found.  Getting 5m off the track I found a colony of about 8 plants.  This one had flowers ranging from buds to spent on one stem.

A detail of the tongue.
Dipodium roseum.
Caleana major

Trees will grow anywhere.
Looking back at the lunch spot.
The bed of the Creek: the flowing water was apparently coming down the diagonal crack.
This is the way down.  About 300m East of the lunch spot.
Rocks have rolled
A goanna

An interestingly reflected beetle (Trogodendron fasciculatum) on our car window.
A Varied Sword-grass Brown (Tisiphone abeona)
A trainee from HMAS Albatross ossibly searching for a better pay offer.  Well below the rim.

Monday, 24 November 2014

Small dog syndrome is a myth

As regular readers will be aware we own a small dog. one Tammy by name.

Some friends acquired - what they were expecting to be - a modest sized dog with some whippet in its genome in the recentish past.  That is called Boson, since he was acquired about the time the Higgs Boson was nailed down.

As is often the case with rescue dogs, history has shown the providing agency really had no idea what the puppy is going to turn into.  I think the whippet element is probably correct - judging by his size I suspect the rest is something of a mastiff nature.  He is a very affectionate beast albeit with a tendency to behave like other Danes would refer to as a svinekotelet.

We have been intending to introduce the two dogs but I have been a tad nervous due to the size differential and cutlet potential.  However today the planets lined up and the two met - initially in our friends family area.  
It was well done that Rob was poised to tackle Boson (as I was for Tammy if she went feral) but in the event unnecessary, as may be gathered from the blurring effect just above Tammy's botty.

They were then let out on the back lawn where Boson tried to incite Tammy to chase him, but she was far more interested in the new smells.

Road works: a millenial oxymoron?

The seed for this post came on the way home from our trip to Orange.  We had three encounters with road works on that leg of which the classic started just South of Boorowa.  A sign warned of roadworks ahead and the speed limit was reduced from 100kph to 80kph as a result.  I realise that there are two reasons for slowing down for road works:

  1. the safety of those in the vehicle; and
  2. the safety of those doing the roadworks.
After about 2km there was no sign of any activity relating to point 2 and point 1 was thus also null, so I resumed cruise control at 100kph.  About 5 km down the road another set of signs appeared (possibly augmented by one suggested that Mr Plod may be doing some monitoring).  Ignored on the basis of experience.  Possibly about 15km South of Boorowa we finally found some guys doing something with a backhoe, possibly using up half of the North-bound carriageway.  So I slowed down while in the area.

This led to some discussion of our past experiences with the descendants of the navvies.  It is pretty much summed up by this cartoon from the great South African strip "Madam and Eve".
What follows is more or less a set of reminiscences which I hope won't be too boring, but I am enjoying writing it!

Going way back into my past (to about 1962) I was helping my Dad dig over his commercial glasshouses and contrasted the physical work he was doing with the activities of some Council road 'workers' in the road outside.  This summarises the processes.

  •     Basically Dad dug, with a fork, about 2 acres of glasshouse every year and added several tons of cow manure: this pretty labour intensive approach kept the soil in good nick and gave good tomato.
  • ·     There were about 6 Council guys with shovels spreading gravel in a hole where the road was being repaired, plus 1 with a dumper and 1 with a back hoe back at the gravel pile.  The process was along the lines of:
1.     the guy with dumper drives off from the worksite to the gravel pile where he stops.
2.     the backhoe guy starts the hoe gets a load of gravel and drops it in the dumper. He then stops the hoe and resumes reading (or at least looking at) the racing pages.  
3.     Dumper dude drives back to the worksite where the Magnificent 6 are leaning on their shovels waiting for him.  He dumps the gravel into the trench and turns off the dumper, probably lighting up a Woodbine;
4.     the 6 dudes then spread the heap out and resume a position leaning on their shovels. Back to step 1.

I haven't kept the exact metrics in my head (shime! shime!) but remember the outcome was that each day, Dad moved twice as much material as the entire mob did in aggregate.

Coming forward a bit, to about September 1973 Frances and I drove from Adelaide to Sydney and came back back via Broken Hill.  Somewhere between Cobar and Willcannia the road surface was being replaced and an old bloke was holding up a stop-go sign.  As we were the first car in line and were going to be there for a while I started a conversation with him.  Mainly about heat and flies I seem to recall - there were adequate supplies of both in the area.  Frances was astonished that my accent changed from hybrid Pom x Adelaide middle class to absolute rustic Ocker.  However it made the old guy happy and gave Frances and I something to talk about for the rest of the day's drive.

We spent 1991 in Ottawa and a Canadian friend commented that Ottawa has two seasons: Winter and roadworks.  This was certainly the case for the Transcanada Hwy (aka route 417).
I don't recall getting a clean 3-lanes-open run on that at anytime except when the snow was flying.

Coming forward another 10 years we spent 2001-03 in Tanzania.  There were 2 approaches to road works there.  

At the basic level villagers would fix up the minor roads (pretty much always dirt) through their village, especially the bits that were shaded by mango trees.  The following image is from Dar es Salaam - on one of the few bitumen roads in that city - but does show the technology used in both rural and urban local works:
In contrast to the UK example above, when we came back an hour later this huge tree had been sliced and all the bits rolled to the side of the road!

For the major roads when work was in progress traffic tended to be sent off on diversions along dirt roads.  
The example shown was just to go round a collapsed bridge.  It could be great fun when it was raining (and in some areas gave added employment opportunities for the local bandits).   Another sample:
The longest diversion I recall was about 16 kilometres! 

Of course this being Africa funds for road works were allocated on a strange basis, formally opaque to any mzungu: so the bitumen road to the National Capital (Dodoma) had a stretch of about 30km that had to be driven at about 30kph or less due to the great number and size of the potholes. No aid project had seen fit to fund fixing this up (or if they had, the funds had been reallocated to some other more urgent purpose with a clearer link to a Minister's re-election prospects - but this was never formally recognised).

Getting up to date the situation around our local area is interesting.  When Palerang Shire or Queanbeyan City Council are using their own staff things go pretty well as the work is done efficiently and it is usually possible to talk sense to all involved (including the lollypop persons).  On the other hand when the State Government is involved there will be layers of contractors involved and the people at the bottom of the food chain (holding the lollypops) are not told anything so cannot answer complex questions such as:
  • "When is this going to be finished?", 
  • "Will both lanes of this, the only road to town, be blocked again tomorrow?" 
  • "Why didn't you do a letter box drop to warn residents the road was going to be completely closed?"
Apart from the Boorowa example at the start of this rant the worst examples I have come across of bone idleness and poor planning was the Pacific Highway North of Coffs Harbour in July 2014.  An episode involving a sign that sent us 5km towards Coffs where a fat bozo told me I had go back the way I had come was close to an award winner.  However the clear winner was an 8km stretch of dual carriageway where 1 lane was blocked by road works signs and the speed limit was 60kph.  Apart from the signs there was no reason not to use both lanes and have a limit of 100kph.

I have heard it rumoured that in Victoria if restrictive signs are in place when the work is completed the contractors cop a big fine.  I do wish such a rule spread to NSW.