(20 October 2017) When they finally made it to our shores these tourists wanted only one thing: poisonous weeds left by exhausted sailors. Whom are we talking about?
Unlike privet and cane toads, the Aussies have embraced these invaders as part of their own ecosystem: ‘true blue’, orange Monarch butterflies.
Now, here comes the interesting thing. According to the naturalist George Gibbs (in ‘Ghosts of Gondwana’) the first milkweeds arrived in the mid 1800s when “sailors discarded their worn-out mattresses and pillows filled with milkweed floss. The seeds of this kapok substitute, germinated and introduced the plants to islands between America and Australia.” Others reckon that the weed was introduced because its poison was used to treat skin cancer. But I like the other story better…. Anyway, the Monarchs that managed to survived arrived around 1870.
Remains the question why the Monarch caterpillars need the poison. Well, they store the poisonous juices of the milkweed in their own skins, giving them a bitter taste which is very unappealing for predators. That helps to survive. And obviously, it is a very good way to get permanent residency as well.
The caterpillar: f/11, 1/6 sec, ISO 200, tripod. 60 mm macro lens. Even the slightest movement of the twig causes problems with 1/6 second exposure time. I took about 20 photos to get one acceptable result.
Ever thought of sending a copy of Green Island in the Sky to friends and relatives elsewhere: the best local present available! Do it now, to be in time for Christmas (or… Dutch only, St. Nicholas). Available at over 20 points of sales on the mountain.