This aim of this blog post is to record some of the everyday events as the seasons change in the remarkable arid environment at Bon Bon Station Reserve; where every year is a new throw of the dice. It's not a record of all the things that happen on Bon Bon, but gives a snapshot of our observations and interactions with nature.
I’ll start with the beginning of 2014; a rather dramatic time that particularly sticks in our memories as record hot temperatures pushed the mercury towards 50ºC.
January – February
From the 13th January to the 14th February there was a consistent period of very hot, dry conditions which put all the inhabitants of Bon Bon under some stress. No effective rain had fallen since July and it was the second very dry summer in a row. The loss of our diesel generator, which backs up our solar power system, meant a scarcity of air conditioning and it made us realise how torrid the conditions would have been for the people who lived here in earlier times.
There was a huge congregation of birds and also some roos coming into the homestead area seeking some relief from the heat and dry (the birds numbered in the thousands; we’d never seen anything like it!)
We were able to provide some water at a small trough and also at a sprinkler or two which kept some of the garden alive. Our bore water pumping system was barely keeping up with demand at that time; it was a fragile existence.
Once the temperature reached the mid-40s thousands of zebra finches carpeted any available shade on the verandahs. They were so thick on the gum trees that a branch broke off under their weight. Birds that normally were enemies made a truce to share the sprinkler - the zebra finches ignored the collared sparrow hawk and even a few wood swallows (a bird that is never seen at water) came in for a bath. Some birds such as pipits did not look for water but sheltered in the shadow of the sheds.
The small, but very fast hobby falcons took full advantage of the dense flocks of zebra finches congregating at the water and seemed to handle the severe heat without needing additional water or shade.
One particularly hot afternoon a kangaroo was seen in the car shed. He hopped out when I took a bucket of water over, only to quickly hop back. He spent the next two days sheltering in the shed.
None of us were surprised when the Bureau of Meteorology put together the climate summary for 2014 and concluded it was the third hottest on record for Australia and maybe the hottest ever globally.
The heat broke with a good belt of storms that came over on the 14th of February just as our grading contractor started work. We drove back from Mt Ernest through sheets of rain (after Kevin the driver carefully parked the grader on high ground). We were very excited to record 20mm of rain at the homestead, but it must have rained quite a bit more to the north east.
Overnight the birds and roos dispersed; the season had broken; a sigh of relief!
The next good bit of rain came in April when we had 60mm scattered across the month. This heralded some decent plant growth. Herbs, peas, daisies sprouted and the mulga flowered; we even had enough water in two of the dams to have some resident ducks!
Weeds also got into their stride. Our buffel grass spraying program got under way by the end of April, firstly in the creek line downstream from the house, then down the old Stuart Highway to another creek 13km south.
After that we started spraying along the new highway, cleaning up regrowth from last year’s spraying and extending the area sprayed further south. In early April we had burnt areas of dry buffel along the highway with the help of Main Roads and the Coober Pedy CFS (Country Fire Service). These areas sprouted fresh growth after the rain, which was easy to spray.
The winter was quite cool. In late June the overnight temperature dropped to 0.5 degrees C and frost was seen on windscreens. Days were still nice with a bit of sun and we noticed quite a few desert pea plants (Swainsona formosa) coming up in the north of the reserve. They completely covered some of the tracks, which made us feel bad about driving over them!
In July many of the emu bushes (eromophilias) were in full flower and attracted huge flocks of wood swallows and a variety of honey eaters.
The second half of the year was generally dry, our buffel spraying season finished at the end of June when the grass started to dry off but the spectacular desert pea display continued well into spring.
The drier weather started to attract birds and kangaroos (mostly red kangaroos but a few western greys) back to the trough at the homestead. The two dams that had water early in the year were dry again. Back in the days when Bon Bon was a sheep station, they relied on wells and bores to water stock. Surface water was not sufficiently reliable to make dam sinking economic. There's not a single named creek on Bon Bon even though some of the drainage lines and lakes are capable of carrying large flows of water. We’ll have to wait for a 'boom' season to see that!
In September, just prior to the start of the annual spring monitoring (where around 50 sites are surveyed for vegetation growth and birdlife), we noticed some dead rabbits in the homestead area. Very quickly it became clear that there was an eruption of calicivirus (RCD) which wiped out most of the rabbits. The younger ones that are less affected by the disease also succumbed with the dry conditions.
In late spring, corellas flocked to the homestead and looked like settling in but eventually moved on to be replaced by a steadily growing flock of galahs. The collared sparrow hawks started nesting in the coolabahs at the house, taking over a nest not long vacated by magpies. The pair of mud larks set about nesting yet again but no luck. They got a decent mud nest made, which was an improvement on earlier efforts. We suspect the sparrow hawks nesting in the adjacent trees may have upset things there.
Other birds seen in quite large numbers in the homestead area were bourke parrots (just before dawn) and flocks of top-knot and bronze-wing pigeons.
Although conditions were very dry, the year ended with quite mild summer weather. The rainfall total for 2014 was 140mm; pretty close to the average.
Thanks to Bush Heritage Australia’s generous supporters, we approached summer with a new generator in place and a more sophisticated inverter and charger; enabling greater solar yield and a more reliable system (air conditioners were back in service). Along with repairs to our bore and with additional rain water catchment and storage in place, we were set to better manage whatever the remainder of summer might bring.
I’ll aim to post the next edition of 'Notes on nature – Bon Bon' in about July.