March 2019 (Painted Lady, Kershaw)

Last month I wrote about how similar the Australian painted lady butterfly is to the UK painted lady, and how puzzled I was about how there came to be two very similar but distinct species.  It turns out that the painted lady butterflies that we get in the UK (Vanessa cardui) is not confined to Europe and North Africa, but can be found on every continent except Antarctica and South America.  This is probably due to their exceptional migration capabilities – they migrate from North Africa, through Europe and the UK and end up near the Arctic Circle, from where in autumn, they migrate back to N. Africa, a distance of about 9,000 miles. 

UK Painted Lady - Vanessa cardui

This degree of mobility means that Australia has had painted lady butterflies probably about as long as painted lady butterflies have existed. Opinions on when butterflies evolved vary from 40 million years ago, to 140 million years ago, but their evolution probably coincided with the spread of flowering plants during the Cretaceous period (79 – 145 million years ago).  There is still a population of ‘UK’ painted lady butterflies (V. cardui) in Western Australia around Perth, whereas the Australian version (V. kershawi) can be found over most of the Eastern half of the continent and must have evolved from an original population of V. cardui.  The genitalia of the Australian adult male butterflies are significantly different to that of the European males so that it is now considered a different species.  It is unclear what caused the change, but evolution of nectar feeding insects can be affected by the availability of suitable forage plants.

Australian Painted Lady - Vanessa kershawi

As a footnote to this tale, I was intrigued by the reference to Kershaw in the scientific name.  It turns out that William Kershaw was a 19th century naturalist and gold prospector who had a passion for collecting moths, butterflies and beetles. His meticulous collection came to the attention of Frederick McCoy at Melbourne Museum, who purchased the collection and employed Kershaw at the museum.  They became great friends and when McCoy described the painted lady in 1868, he dedicated the species to his friend William Kershaw.

It was good to get back home after our Australian trip, even though the weather was cold, dull and wet for a few days. But we’ve had a week of mostly sunshine since then so that we can get out and see some of the early signs of nature coming back to life as winter loses its bite.  It was nice to see the familiar birds at the bird feeders – not as brash and colourful or noisy as the Australian birds but just as beautiful in their own right.  I thought that I caught a glimpse of a brambling but it may well have been a slightly scruffy chaffinch.  Brambling are one of a number of species that migrate to the UK when their food sources run out in Scandinavia.  This year there has been a shortage of beech mast which is normally reliable and long-lasting forage for the bramblings.  They normally feed in small flocks, which makes the solitary bird that I saw even less likely to have been a brambling.  Other Scandinavian species that we may see trying their luck over here are redwings, fieldfares and waxwings.  We had waxwings at Pett Level a few years ago, though I didn’t get to see them.

It was good to see snowdrops in the garden when we got back. 

We have now managed to increase our one solitary clump and now have 4 clumps of them, though clump is perhaps not the right word to use for the two that have only one flower each.  Pett village seems to be bursting into flower early this year with several verges putting on a good show of crocuses.  Not long to wait now before we hear the first lawnmower of Spring.

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