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Keep in touch with the good earth
Saturday
Apr122014

A royal visitor - a Monarch butterfly in our garden

It is autumn, a good time for planting shrubs - they have time to settle in with the rain and our relatively mild winters before the spring gales stress everything.  I had some swan plants ready as I want the garden to be more welcoming to Monarch butterflies next summer - none had visited our garden this year despite a butterfly-friendly abundance of flowers.  But I didn't have to wait till next summer - the swan plant foliage was being devoured already.  One hungry caterpillar was at work, its little black filaments waggling as it munched, the claws on the front legs seeming to direct the leaf to its mouth...They might be fussy about what they eat (basically just milkweed plants thank you) but they are not what you would call fussy eaters - "eating machines" is one epithet.  The caterpillar (also known as a larva and called an instar if it is between moults) demolished much of the still modest sized swan plants, then disappeared.  Apparently they often go walkabout before the next stage.Not too far away, the caterpillar had climbed into a plant of Ballotta pseudodictamnus, a pretty little shrub with grey-green leaves covered with soft white hairs.  Its rear prolegs were hooked into a dense white silk mat that it had woven on a leaf and the caterpillar, now called a pre-pupa, was dangling down, ready to go through its fifth moult to emerge as a green pupa.  You can see that change is afoot - the skin (exoskeleton) looks a bit more transparent, the pre-pupa is paler and lacking the healthy glow of the earlier instar.  Fortunately the autumn rains (hence raindrops) did not cause any problems. 

Next stage - pupa!

The soft stripey skin was shed to reveal the harder protective exoskeleton of the green chrysalis or pupa, blending well with the foliage - except for the bling.  Apparently the gold  and black band marks the end of the abdomen and the other gold spots occur over the thorax, the wing bases, and the eyes. When fully developed the butterfly emerges head first from the lower end of the chrysalis.  You can see the pattern of the wings through the transparent shell.

I had read that the pupation stage for a Monarch butterfly was about two weeks.  So when a month had passed, and the chrysalis looked black and lifeless, I had given up hope - it was too cold and wet I thought (the weather had suddenly changed.) 

And it turns out that the weather does indeed affect the pace of things.  The butterflies take longer to emerge (eclose) in autumn.  But if they survive the nastier autumn conditions they will then live much longer than their summer siblings.  They have a big task - keeping the population going by migrating and overwintering in warmer locations, ready to get started when winter is over. 

Not knowing this I had stopped checking, and I was very surprised one very wet morning, to see...I am tempted to call this the "empty nest" - technically it is the "exuvium", the protective pupal exoskeleton no longer needed, metamorphosis complete.  So the butterfly had gone, just the imprint of its wings left behind.  But had it flown? How could it survive?  It was horrible weather - gales and rain and mist.  My heart sank.  I had read that cold and moisture can be deadly for them. 

But it is all relative.  I had forgotten that they are also tough little creatures.  They have been seen by glider pilots at 11,000 feet above ground.  And they are known (like glider pilots) to catch thermals which lift them up high to the strong winds - but only the wind heading in the right direction (how do they know?) for their migrations covering distances as great as the journey from southern Canada to central Mexico.  And then it didn't take long for me to catch a glimpse of orange through the tangle of grass being buffeted by the wind.The imago - an adult Monarch butterfly.  Out only a few hours, apparently, with wings not quite completely expanded (butterflies emerge or "eclose" with rumpled little wings and haemolymph is pumped into the wing veins over several hours to expand and stiffen them) and sheltered near the empty chrysalis.  I was worried about how the wind was whipping the long brown leaves of the native grass (Carex buchananii) around and disturbing the butterfly's balance.  But somehow she held on, keeping down and away from the wind and rain.She moved a little, occasionally fluttering her wings - but not very open.  This protected them from damage and anyway, butterflies need warmth to get moving, and there wasn't any!  But she seemed to be exploring - coiling and uncoiling her proboscis.  And those eyes - what does she see, I wonder.

You may ask - how do I know this is a female Monarch?I know because of her wing markings - the stripes on the wings of a female are thicker and don't have the spot on them which marks the males.  This moment was a rare one - a glimpse of her wings outstretched.  Mostly she barely moved and huddled, conserving energy and avoiding damage by sheltering down a bit and out of the wind, with raindrops on her antennae and her hairy thorax.  It didn't look promising for her.  But the next morning, she was gone. 

So - we were visited by a Monarch (butterfly) - and a monarch (human) of the future.  Her emergence coincided with a visit of William and Kate, royals from England (a hangover from our colonial past.)  The really wet weather has coincided with their visit - to the point that people from the drought beleaguered areas of Northland jokingly suggested that William and Kate go up there and take the rain with them.  If she has the chance, this lovely little lone butterfly may fly north too, and join the other overwintering Monarchs in a warmer part of New Zealand.

Sunday
Apr062014

Fresh green fronds of wheki, the rough tree fern

Although the days are much shorter and the colours of autumn are beginning to appear, we are still enjoying warmth and sunshine.  The mostly evergreen New Zealand plants can look subdued when the sky is grey, but sunny days highlight the textures and brighten the different greens.  However, even in the shade of the bush there is fresh green to be seen.  Unfurling new fronds of wheki (Dicksonia squarrosa) glow against the deeper green of the mature fronds and the bristly brown hairs of the frond stalks.Wheki is also known as the rough tree fern.  Presumably this is because the texture of the fronds is quite harsh to the touch, but the plant itself can also look a bit "rough" too - old and dead brown fronds hold on to the trunk, giving a raggedy look - not the thick skirt of dead fronds typically seen on the related wheki ponga (Dicksonia fibrosa).  Wheki is a medium sized tree fern found throughout New Zealand, often near streams and in damp places.  It is also quite resilient - bare trunks are used for fencing, and they can quite delightfully come back to life, sprouting from buds on the trunk.   

The trunks are slender and up to 7 metres tall.  The fronds of wheki, 1.5 to 3 metres long, are smaller than those of other tree ferns and they grow in almost horizontal array.  Wheki can cope with some sun and wind, but it shows - they tend to look more weathered and scruffy.

This one, in the fern glade at the Otari Native Botanic Garden here in Wellington, is in an ideal situation - a sheltered shady area that is not too dry. 

Here the filtered light highlights the textures and shapes of the fronds, which seem to sparkle against the darkness of the shade cast by the big trees above them.

Monday
Mar242014

Peaceful waters

Island Bay has many moods.  At sunset on this early autumn evening the water is calm, with subtle texures reflecting the gentle water movement.  The colours of the sunset are reflected in the water - pinks, lilacs and grey-blue.  A small group of seagulls float on the water, giving scale to an otherwise quite abstract sight.

Tuesday
Mar182014

The Golden Bearing - a sculpture by Reuben Paterson in Pukekura Park

Pukekura Park in New Plymouth is a lovely green and well-tree'd hilly space, the slopes surrounding peaceful waterways.  Located in a valley described as originally swampy and tree-less, since 1876 it has been shaped (creating an open central lake meandering into a sleepy sheltered upper lake, a number of smaller ponds, a fountain and water cascade that play on request) and planted with exotic and native trees and plants to make that curious mix that is a garden - nature groomed for our pleasure.  The upper lake area is still, reflective, the exotic and native plants a lush and dense presence on odd little islets and on the water's edge.  Such a space creates an atmosphere that is evocative - we are inclined to project our feelings and ideas onto it - it can be experienced as mysterious, peaceful, magical, foreboding, comforting, and so much more.  If we linger we can breathe in the scents of plants and water and soil, and hear the quiet sounds of the life around us.  And then - this bright apparition.A sculpture,  The Golden Bearing by Reuben Paterson , on the Boatshed lawn, an opening amidst the trees.  Descriptions of the sculpture, a golden glittering 'archetypal tree form' installed in a park - 'an unnatural environment of natural beauty' - suggest that the work questions ideas of artificiality, reality and 'natural' environments, and that it references many ideas including the concept of the golden mean, classical composition and the framing of images, of focal point and navigation by the glittering stars (nga whetu), and so on.  

At 4.5 metres tall it was imposing and arresting.  It clearly delighted people who came upon it while I was there.  Some seemed to want to climb it, others asked "is it real?"  I am not sure how much thinking really happened - a lot of snaps were taken, including mine.  And I was left wondering about thinking and feeling, our senses and emotions, and how we connect and relate to nature.  And while I appreciated the stimulus to think about things, I was pleased to resume walking amongst the trees, soaking up the quiet and green and turning off the thoughts for a bit.

Tuesday
Mar042014

The daddy longlegs spider and the blowfly - a domestic drama

"Daddy longlegs" is a name used for more than one species, as is the case with many common names or nicknames for plants and beasts.  Needless to say, this can cause confusion.  In the northern hemisphere "daddy longlegs" seems to be used most often for "harvestmen" - creatures which are arachnids, but not spiders.  It is also used for "craneflies" which are flying insects.  But the creature that I know by this name is a spider, Pholcus phalangioides, also known as the cellar spider - thus named because it tends to hang out in shadowy places, often in cellars or in warm quiet corners in houses, where it makes its rather raggedy tangled webs and can do good pest control service. 

In a shady corner I saw this daddy longlegs at work.

Dangling above a hapless blowfly, it was wrapping it up in silk - first trapping its wings, then banding its legs in a tangle of white threads.

Apparently daddy longlegs can cast their silk at their prey, a bit like casting a fishing line.  Once the prey is caught, they wrap it up ever tighter and then can deliver their venomous bite.

Despite their delicate appearance - their bodies are 6-9 mm long and their long legs are thin and translucent - they can catch prey much larger than themselves.  In addition to flies, woodlice and so on, they are known to catch and eat nasties like the very venomous Australian Redback spider. 

This may have led to the myth that their venom would be deadly to humans if only their mouthparts could puncture our skin.  Wrong on both counts!  Their venom is apparently not that bad on the scale of spider venom toxicity, and they are capable of making tiny little punctures in our skin.  They just don't seem to do it that often, even though on the whole they prefer to live in our houses and are often there in great numbers.  And watching this one, I'm happy not to be the object of its intentions.The spider, having completely swaddled the fly, appears to be envenomating it - biting and poisoning it.  And while I know that a spider has got to eat, it did feel like watching a horror movie, a chilling domestic drama.  Sometimes it is hard not to anthropomorphise.

I didn't just witness a skilful killer at work, while doing my researches I also found a new word.  Daddy longleg spiders are synanthropes (from the Greek for "together with" - syn, plus "human" - anthro).  A synanthrope is a member of a species of wild animal that lives near and benefits from associating with humans and the environments we have shaped around us.  It appears that we benefit from the hunger of the daddy longlegs too - they like to eat the bugs we don't like to have around the house.