Saturday, 26 January 2019

February 2019


Well, we are still in Australia, and have survived hailstorms, torrential rain and 43 degree C heatwaves.  As I write this, the weather has calmed down to a balmy 24 degrees which makes the wildlife-watching much more comfortable.  While in the Australian Botanic Gardens, I photographed some butterflies that looked very similar to the painted lady butterflies we get in the UK and Europe.  When I investigated, I found that it was an Australian painted lady – a different species to the UK one.  However, when I compared the photograph to a photograph of the UK species, there was hardly any difference between the two.  There were small differences but it is not uncommon to get small differences between individuals of the same species.  The scientific names are different – Vanessa cardui for the UK species and Vanessa kershawi for the Australian species. 
Painted Lady UK/Europe version

Painted Lady, Australian version
This suggests that they are different species and not populations of the same species geographically separated, but it is puzzling how two separate species came to look the same.  There is a concept called ‘convergent evolution’ where widely separated species evolve similar characteristics due to a common threat.  For example, there are poison frogs in Madagascar as well as in South America; they are completely unrelated and have evolved different poisons as well as bright colours to warn off potential predators – same ecological pressure with similar solutions.  But the pattern on butterflies’ wings doesn’t seem like the same sort of thing, it looks more like a way of attracting a mate than responding to threats.  When I get back to a reliable internet service, I intend to email some butterfly experts to see whether painted lady butterflies were at some stage introduced to Australia, and who the Kershaw mentioned in the scientific name of the Australian version was.  Watch this space.
Wildlife watching can be a frustrating business – some days you see hardly anything new, sometimes you see hardly anything, and sometimes you are just plain lucky.   We had a very lucky day while staying at Fish Creek in the South-east of Victoria state.  We decided to visit a nearby nature reserve which had good reviews but on the path through the reserve saw little but a few snakes that shot away before we could get a good look at them.  At the end of the path was the steel skeleton of a new bird hide that was to replace one that had been deliberately burned down (it seems vandalism is a global phenomenon) where we met a fellow bird-watcher.  There were not many birds about but when I focussed on one of the ducks on the lake he asked if I had taken its photo as he thought it could be a freckled duck – a real rarity.  The ducks were a long way away so I changed to a longer lens to try and get the closest shot, but the light was against us and it wasn't clear from the camera screen what the duck was.  As he was a local, we asked if he knew anywhere else nearby where we may be able to see more species.  He told us about a trail at Waratah Bay across heathland where we may see something different, so later in the day, we went to try and find it.  We were successful, but it was a long dreary walk uphill and we were tired.  It was basically a fairly long straight fire-break and we didn't even see a kangaroo.  So, we gave up and walked back and Maya called my attention to a bug on the path and we stopped and were chatting about something and I idly glanced up at a tree where there was something that wasn't a nest and had a furriness to it. 
Koala Bear - in the wild!
I pointed it out and Maya got as excited as I was becoming and as we walked nearer to the tree, the koala turned its head to look at us.  We stared back for a good long while as it was the first koala either of us had seen in the wild and this is my fourth trip to Australia.  To cap it all, when I got back and looked at the photographs, the picture of the duck showed that it was indeed the rare freckled duck.  Yes, just plain lucky!
Freckled Duck - Bald Hill Creek Nature Reserve


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