Following a tip on Orchids

 The Grand Final of the AFL was boring in the extreme so we went to check on a sighting of Beard Orchids reported by a friend.  That was at point 1 in the map.

We found beard orchids very quickly.  According to iNaturalist these tow images are Calochilus paludosus.

This one seemed 'different'.  Possibly just aged but I have called it C. campestris, Copper Beard Orchid.

We then explored the track into the Water Treatment Plant (WTP).  Area 2 on the map. Few Beard Orchids but many buds of Thelymitra sp. (Sun Orchids).  The weather was not propitious for the flowers to open, being about 15C and very windy.

One small Onion Orchid (Microtis sp.)

We moved up to the track under the power lines (3 on the map).  

Despite the weather referred to above this one has a bud open.  I feel safe calling it Thelymitra ixioides - the default Sun Orchid in this District.

On the verge of the main road, heading towards point 2,there were many Glossodia major (or whatever the DNA freaks are calling Waxlip Orchids this week).

A few other images.  I think this (from area 1) is Thelionema caespitosum in a white, rather than blue, form.

Mitrasacme polyforma from Area 3.

When we got home Channel 7 was still showing proceedings from the G.  I hesitate to call it football as the Lions were around 80 points in front.  The Swans had given up and the Lions were playing a style of football I remember from playing in Torrens St, Mitcham with my mates: dobbing the ball from end to end with no real purpose.  Glad we went out for a nice walk!

Testing the Kayak (again)

 For a range of reasons, but mainly poor weather and/or bogans in power boats, we have not used our kayaks for about a year.  I decided that this was the only way to get some snaps of the waders on the sand bars in front of Captain Stevenson's Point.  So I took one of the kayaks off the trailer and headed for the wharf to check things out.  I had three objectives for this exercise:

1. Prove to myself that I could launch etc the kayaks on my own.  A specific sub-objective here was not to fall in the water while launching or landing the kayak;
2. Get to check out the birds on the sandbar;
3. Not cause too much disturbance to the birds.

All 3 objectives - and the sub-objective - were met.  

The route was intended to avoid the sandbars along the way, thinking the channel serving the Campground moorings was a  pretty good idea.  So it was: trying to shortcut ran out of draught rather quickly but no biggy.  The last few metres (yellow arrow) were shallow, so pedals out and paddle in.  From a combination of Google Earth and eBird tracking I think the distance from launch to landing was about 600m, so not really worthy of a Viking saga.

Here is my track on the sand bar as recorded by eBird.  There was less exposed sand outside where I walked: the image was taken on March 30, I suspect at low tide (and there had been little rain for about 10 weeks).

Photos of birds,  These are not unduly high quality as I took my old Panasonic camera in case the sub-objective was not met!

Caspian Terns and Red-necked Stints.

Stints and Red Knots.

Stints.

WRT to objective 3 the birds seemed unfussed by my presence - I did TRY to maintain an ethical distance - apart from where a couple of Silver Gulls, not part of the main flock, went postal and the whole lot (my guess was ~500 Crested Terns) took wing.  They just did one circle and landed again.

There were about 40 Bar-tailed Godwits in 3 groups.

One Eastern Curlew - I think a male from bill length: IMO the female would be about 30% longer.

Altogether a pretty successful outing.  It seemed that the numbers and diversity of waders were somewhat less tan some recent visits.  No Grey Plover, Greenshank or Turnstone which being on migration have probably just moved on.  Only a single Red-capped Plover and no Double-banded Plovers (the latter having possibly gone to their breeding grounds in New Zealand).

Variation in temperatures

 I have recently changed my calculation of the long term averages in my assessment of the temperature anomaly from a series starting in January 1993 which included data from (or based on) BoM data at the Airport site and my Weather Station (WS), to a series starting in January 2019 solely from my WS.  This was done to avoid differences due to the change in site,

I knew there were differences in maximum temperatures due to the cooling effects of sea breezes on the BoM data and had made adjustments sing regression models to compensate for that.  However recently I had decided that there might also be less significant, but still regular differences in the minimum series.  Rather than fiddle around trying to adjust the minima as well - giving a rather artificial set of data from 1993 - 2018 - I decided that a 6 year series would give a "good enough" basis for noting if a month was generally warmer/colder than normal (which is my aim in calculating the anomaly).

In working on the September data I noticed that the average temperatures were all over the place, as shown by the dashed lines in this chart.

This made me wonder if:

• September was an unusually variable month; and/or
• If the variability was higher in the WS series than in the previous longer series.

So I calculated the average daily maximum and minimum temperatures for each month and the Standard Error (SE) of those averages.  I then calculated the Relative Standard Error by expressing the SE as a % of the average.  That gave the following chart.

There are several interesting points in the chart.

1. Minima are subject to much greater variation than maxima;
2. September is variable but not as variable as July/August;
3. The WS series for minima is less variable that the hybrid series (possibly to be expected as it is much shorter so less chance of outliers);
4. The two maximum series are very similar (suggesting that my adjustments were satisfactory); and
5. Overall, the differences in the maximum series suggest the recent years are warmer than the earlier years (but there isn't a long enough WS series to make much of this).

I don't see any need for change as a result of this investigation.  I will keep the original (longer) series but use the WS-only series for calculating the anomaly.  If I find a rainy period I might investigate adjusting the old minimum series as I did the maxima but it is a fair bit of effort.

Some recent bird sightings

 I have seen an image of a Black-shouldered Kite flying around with a twig in it's beak.  I am happy to record this as a breeding record.  Also the Silver Gulls have assumed the position on Seagull Island. 

The Masked Lapwings running a reign of terror on our neighbours' lawn have hatched the first chick. 

Three more to go!

That was then, this is now (about 0900 on 19 September)

By the early morning of 20 September the chicks were moving about.

This image shows that they are several metres from the nest, on which the other parent is sitting with ? underneath her!  On checking a little later it was a chick in the nest: all 4 eggs have hatched.

A pair of Whistling Kites have been hanging about in the big Angophoras near by for some time.  I haven't seen them adding to the nest yet, but they perch near it.

I also took a couple of snaps of Common Bronzewings because why not ?

I went for a drive round the airport at lunchtime.  Although the last 2 months have been average or less in rain some areas are still boggy so I cut my route a bit short.  Sill got some interesting birds.

A Fan-tailed Cuckoo on the fence.

2 - I am tempted to say a pair - of Black-shouldered Kites, a little further down the fence.  I am uncertain whether these are likely to be the same 2 birds seen by another observer in Martin St.

A close up of the nearer bird!

Coming home via Betka I found 2 Hooded Plovers on a shingle bank in front of the car loop.

Observations on 6 September

 The good stuff began early with a sighting on our morning walk of 5 Australian Figbirds (1 male and 4 females) near Broome St.  When we first came to Mallacoota as visitors (2013-14) a Figbird sighting would get people driving from Melbourne to add them to their Victorian list!  Then as we walked - probably giving our rate of progress somewhat the best of it - up the mountain that is Angophora Drive a small flock of 5 Little Lorikeets went over and scored Bird of the Day.

I swung by Cap'n Steve's Point later where the highlight was 10 Caspian Terns.  Here are some of them, mixed in with a few of the 500 Crested Terns on the sandbars:

There were 37 Bar-tailed Godwits on the edge of the sandbars.

In the afternoon we went for a walk up the Narrows, mainly looking for flowers.  Many of the orchids we had seen on previous visits had gone over but there were still a few good plants around.

Indigofera australis is beginning to hit its straps.

As is Pultenaea daphnoides.

Daviesia latifolia was an addition to the Sptember list for the District.  A classic 'egg and bacon' flower.

Glycine clandestina was evident rather than being clandestine!  (NB the big leaves are Hardenbergia, the sets of 3 are Glycine.

Viola hederacea

Another addition to the September list: Prostanthera rotundiflora.

Finishing off a good day, as we drove along Lakeside Drive about 6:30 a Southern Boobook flew in the bushes on Stingray Point.  We are likely to hear one later, so it didn't beat the Lorikeet for Bird of the Day.

U3A plant walk: September 2024

 As there seem t be flowers around we started up our plant walks again.  After meeting at the tennis courts we went to the powerlines opposite Karbeethong Rd.  I wrote down 21 species of plants listed in the page "Seen on walk" in this Google Sheet.  Here are a few flower images.

Aotus ericoides

Comesperma ericinum

Thelionema umbellatum

Xanthorrhoea resinosa: this is the local species without a trunk visible above ground.  

Some interesting patterns of grass in one of the remaining puddles.

August 2024 Mallacoota Weather report

 The BoM has the Climate Outlook at "Neutral" between El Nino and La Nina with a tendency towards La Nina.  That would imply an expectation of above average rain.  Not in this District in August: very dry (in terms of rain at least) but also ending up extremely warm overall, compared to average temperatures for the month.  As is often the case, it appears that the answer is blowing in the wind (if Mr Zimmerman doesn't mind me borrowing a phrase).

Rain

What is this thing called 'rain'?  We totalled 22.6mm for the month, the 6th lowest since my records begin in 1977.  Obviously well below average (35.7% of median) but better last year's miserable fall of 13.8mm.  The benefit of a low fall is that the low daily falls actually appear in a chart!

We are however still well in front of 2023 in total (by 285mm) and the pro-rata estimate for the year as a whole is still 1066 mm.

Temperatures

The final value for the temperature anomaly was +1.8C.  That is not the highest value of the anomaly I have calculated (there are 3 higher values) but only +2.0C in November 2020  is significantly higher.  Despite this high recent value, the 12 month moving average still suggests a downward movement may be evident, although the trend of the average is still upwards.

The development of the anomaly through the month shows a rather cold start to the month followed by a steady increase.

The extreme temperatures show that the cause of the high anomaly is the very high maxima recorded in the month.

A further point of interest in temperatures was the daily ranges.  For most recent months a combination of high minima and low maxima has meant the daily temperature range has been below the range of the averages for a high proportion of days in the month.  For August the range in the average was higher on only 6 days, reflecting the consistently high maxima and low (or at least relatively low) minima.

Minimum Temperatures

The average minimum for the month was 8.39C.  The highest minimum temperature was That was the highest recorded since my broad series (Airport and home) begins in 1993.  The next chart shows the 6 year series of readings on my weather station.

It will be no surprise that this year is top of the pile.  The highest minimum temperature was 13.3C on the 13th: this was =6th highest August minimum.  11 days were more than 1 SD above the monthly average (ie significantly hot).

While there were 3 consecutive days of minima more than 1 SD below the monthly average, these were not accompanied by significantly low maxima and thus do not amount to a Cold Spell.  

Maximum temperatures

The average maximum for the month was 19.12C, the highest average maximum for August by 0.5C. 

The highest maximum was 'only' 23.7C which is the 21st highest August maximum in my records (including a small adjustment to make the WS and Airport data more consistent).  There are two other WS record of higher maxima.  What has caused the high average is the number of days significantly above the monthly average maximum: 

1. only 6 days were below the average maximum for that date;
2. of the 25 days above average 
1. 15 were more than 1 SD above the monthly average and 
2. 4 of them were more than 2 SD above the monthly average.

Further, there were 10 days in which both maxima and minima were significantly above average.  It seems a little panic-ridden to describe a period with a maximum temperature ~22C as a "Heat Wave" but it is certainly significant that of the last 19 days of the month only three of the extreme temperatures were below average for the date and of the last 8 days of the month only 2 readings were less than 1 SD above the monthly average.

Humidity

The average morning rH at 82.1% was well above average while the afternoon reading was close to average.

The values for 31 August - especially the afternoon reading - were so low that I assessed the pattern through the day.  It looks normal so I will regard this as an effect of a constant wind from the NE.

Wind

I have difficulty with wind, as my WS is far from optimally exposed (too low and too sheltered from the Southern half of the compass).  There is relatively limited information available (at no charge) from BoM. The average daily wind run this month was about normal for August.

Of more interest this month is material about the the direction of the wind.

This shows that 61% of the records of wind (excluding those with no wind run - ie calm) in August came from the segment of the compass from NW to NE (31% of the compass).  Looking at all WS records 42% of windy records came from that segment.  I have taken this above as an explanation of the Humidity data, and expect that it also contributes to the high temperatures observed.

Tempest data

A friend operates a weather station neat the Wharf using the Tempest app.  This includes some very interesting data on Lightning Strikes (within 40km) and Solar Radiation.

The solar Radiation chart is particularly interesting in understanding the need for running the hot water booster and why my solar feed in varies (beyond the appalling feed in tariff now offered).