Getting close to NSW!

 Dale announced that he was taking a tour up the Wallagaraugh River on 26 November, and I thought this was a good chance to add a few more species to the District list, even though a trip the previous Saturday (with 17 expert birders on board) had found 65 species.  So I joined the group on the Gipsy Princess at Gipsy Point.

Here is the route marked with orange arrows (other symbols will be explained below).  The double headed arrow marks the turning point, very close to the State border.  This was not due to fears of a check point, but the presence of a small waterfall blocking the way (after dodging a few submerged rocks in the final few hundred metres).  

This is the view in the upper parts of the trip.  The area was thoroughly burnt in the Black Summer fire but has regrown densely.

We paid close attention to the vegetation at the Johnson Bridge (red arrow) as Black Bittern has been seen there in the past.  No joy on this trip.  However when we got to the point marked with '1' an unusual looking dark Bittern-shaped bird was seen on the bank, jumping up into a tree.

Much excitement ensued as we thought we had seen what the 17 experts had dipped on: the aforementioned Black Bittern.  I tried to log on to the Mallacoota Birds Facebook page (being a caring and sharing person, not gloating at all, no Sir, not me).  Unfortunately my phone didn't have coverage so that failed.

This was actually a Good Thing, as when I compared my photos (and those of others) with the paintings in The Australian Bird Guide it was clear that what we had seen was not a Black Bittern but what we would call a Striated Heron.  eBird has renamed this Little Heron - the detailed reasons for which they demand coin (although it is summarised in this which also contains a number of threats of future changes - an ominous sign that Avibase won't stop continual random changes to taxonomy).  Wikipedia links to the 34 page Masters 'thesis' as the explanation, which is also referenced in the eBird summary.  So poor connectivity saved me from making a public chook of myself.  

That is still a very good bird as the Southern limit of their range is usually around Bateman's Bay and there are only 2 eBird records West of Mallacoota.  They have not been recorded in the District since January 2024.  Another photo.

We had a few sightings of White-bellied Sea-Eagles but they showed no interest in our boat.

This pair were in the vicinity of a nest which had been occupied by young until very recently. 

On Dale's previous trip 12 Azure Kingfishers had been recorded including a bird entering a burrow with a small fish.  We saw none on the way up, but did record 3 on the return.

The weather was growing close to ordinary by the time we turned, possibly accounting for the absence of reptiles on the banks.  One Gippsland Water Dragon was seen in the upper reaches.

Overall we recorded 41 species for the trip which was quite good.  A number of very much expected species (including Lewin's Honeyeater, Pacific Black Duck, Chestnut Teal and White-browed Scrubwren) were among the MIA.

October 2025 Weather Report

 The weather recording in October was dominated by two themes:

1. The impact of the Sudden Stratospheric Warming (SSW) over the Antarctic which disrupted the expected climate drivers over Australia; and
2. The downgrade of the Bureau of Meteorology (BoM) website.

The first of these caused the dry weather experienced in September to continue into the first part of October, but appears to have gone away for the last week of the month.  There are some signs that community outrage regarding the second event is having some effect although that will probably not be known until the new Director of BoM takes up his Office later in November.  As this report is mainly concerned with data from personal weather stations (WS) this will probably have little impact on what I have to say.

Overall the month has been quite moderate: rain has ended close to median fall; temperature anomaly close to zero; and wind runs moderate.

Rain

The impact of the SSW (and its disappearance) is shown in daily rainfall for September and October 2025 compared with mean falls (2019 onwards).  This should be viewed against the situation in early September, where forecasters were suggesting that the drivers of the climate (notably IOD  and La Nina) were suggesting a wet Spring.

This is emphasised by my usual chart comparing this year, last year and median fall for months. 

As a result of the good falls in the last week of the month the rainfall for October has got to 93% of the median fall for the month (for year-to-date we are at 135% of the median fall).

The heavy falls in Autumn and Winter mean that the pro-rata estimate for annual rainfall is still holding up at a high level, having passed the annual median fall on August 24th.   

The current pro-rata estimate - 1231mm - if met would be the 8th heaviest annual fall of the 47 years for which I have records from my WS or the BoM site at the Airport.

Temperatures

The temperature anomaly for the month ended at +0.13C after a fairly variable month.

The time series for the anomaly continues as a positive and the moving average is in the same band as recent values (but the trend line is showing a drop in the last few readings).

A notable feature of the temperatures over the month - especially the first  weeks - was the great range of temperatures.  This was drawn to my attention on the 5th when the temperature range was 20.1oC and is illustrated in this chart.

Minimum temperatures

The average daily minimum was 10.13oC somewhat below the average October minimum recorded at my WS.  This continues the cool values since June.

I recorded 8 minima significantly below the monthly mean minimum and the coldest value  - +5.7oC  -was very significantly below mean.  Three days had significantly above-mean minima.

Maximum temperatures

The average daily maximum was (not a surprise, in view of the extremes graph above) well above (+1.4oC) the average for my WS.  This gets it to "the top of the heap" for recent years but still well below the 23.5oC average achieved at the Airport in October 2015.

I recorded 2 maxima significantly above the monthly mean maximyum and  days very significantly above the monthly mean.  The hottest value - +30.4oC  - was very significantly above the mean and the 6th warmest October day recorded (the hottest at my WS was 34.9oC on 31/10/2019).  Only 1 day (27th) was significantly below mean maximum.

Humidity

The chart for relative humidity at standard times shows a very orthodox pattern with afternoon values generally below those for the morning.  In both cases the series show a lot of variability from day to day.

Wind

The daily runs for the month as a whole were quite variable for October. 

Looking at the month as a whole the average daily run at my WS was very low.

I was able to locate the table of BoM observations for October and this showed that many of the observations of wind were from the ESE to S section of the compass, from which my WS is particularly sheltered.  So I believe the value shown is an egregious understatement of the windiness of this month.  This is particularly annoying as I had hoped that the wind direction would be helpful in explaining the temperature observations.

Tempest series

A friend with a weather station near the Wharf has provided access to his data published on the Tempest network.  This includes data for solar radiation and lightning strikes.

The records for solar radiation show a high level of seasonal variation so I have included a 12 month moving average which removes that effect.  The result shows the level to be very close to  constant, with a range from 165 to 178

The data for Lightning strikes relates to a circle of 40 km radius around the site ...

... and includes data from other sources (see https://help.tempest.earth/hc/en-us/articles/360046877513-Lightning-Detection).  The very high number of strikes (6941) in February 2025 cause  some issues in charting the data using a normal scale so I have used a Logscale (Log 100 = 2.0; log 6941= 3.8414 etc).