Friday, October 27, 2017

"Seriously, we’re all going to die: Insect populations are at apocalyptic levels"




You may have read in the news of a catastrophic decline in insects based on research conducted by scientists from Radboud University in the Netherlands and the Entomological Society Krefeld in Germany. It has been all across most news platforms for the past few days and makes for worrying reading. 

The number of flying insects has declined by more than three-fourths since 1989, threatening food supplies

This is the conclusion of a study published on Wednesday in the peer-reviewed scientific journal PLOS One:

"Our analysis estimates a seasonal decline of 76 percent, and mid-summer decline of 82 percent in flying insect biomass over the 27 years of study, we show that this decline is apparent regardless of habitat type, while changes in weather, land use, and habitat characteristics cannot explain this overall decline."

The study added, "Loss of insect diversity and abundance is expected to provoke cascading effects on food webs and to jeopardize ecosystem services."

The plight of honeybees has been well documented and it is now widely believed that a type of pesticide known as 'neonicotinoids' are responsible for the precipitous decline in honeybee populations.

Coincidentally, I have been reading Rachel Carson's 'Silent Spring' which deals with an ever-growing threat posed by insecticides and pesticides. She points out in quite graphic form how there is a global threat from the misuse and over-use of these chemicals, together with intensive farming methods. The really sad thing is that her book was published 55 years ago, and we seem to have learned nothing!

Or maybe we have, but just don't care, because nature comes second to the pursuit of the dollar!


Even that back-stabbing numpty Michael Gove had this to say on the subject: The Environment Secretary said "heavy farm machinery and overuse of chemicals was boosting short-term productivity but would render large tracts of soil infertile within a generation."



A reminder from LWEC (Living With Environmental Change) about why pollinating insects are vital to our ecology:


Why are insect pollinators important?

Bees, flies, wasps, beetles, butterflies and moths are part of a nation’s biodiversity and natural capital. They have intrinsic value and provide environmental and economic benefits because:


 — Pollinators improve or stabilize the yield of three-quarters of all crop types globally; these pollinated crops represent around one third of global crop production by volume.

 — Many fruit, vegetable, oil, seed and nut crops that provide vital nutrients for human diets worldwide, including more than 90% of our vitamin C, are pollinated by insects.

— The cultivated area of pollinator-dependent crops has risen, raising worldwide demand for insect pollination services three-fold since the 1960s. Globally the crop production attributable to insect pollination was valued at US $215 billion in 2005.

 — Honeybees, but also bumblebees and solitary bees, are managed and traded commercially for their pollination service. Wild pollinators are at least as important as managed pollinators in providing these benefits.




That opening to this update was a bit heavy eh? In fact it was heavier than regret! And so in true BBC 'One Show' fashion, let's move on to something  a bit more ...


My last update was all about caterpillars, which by the way are doing fine, there are just 2 left eating now, the others have all pupated. It is strange though how they all came from the same batch of eggs and yet the final two are about three weeks behind the others. Anyway, I will continue the theme with some more caterpillars in this update. 


Here's what the excellent UK Moths website has to say about the Convolvulus Hawk-moth:

A large species, with a wingspan of over 10cm, this is a migrant in Britain, appearing sometimes in fairly good numbers.
It most often occurs in late summer and autumn, usually with influxes of other migrant species, when it turns up in light traps and feeding at garden flowers, especially those of the tobacco plant (Nicotiana)

Although larvae are sometimes found in Britain, usually on bindweed (Convolvulus), it does not regularly breed.

I was very lucky to get some early (probably 2nd) instar larvae to rear. They came to me looking a little like Twiggy on a diet (ask yer gran who Twiggy is, and I don't mean Ramirez!) Oh! Hang on...here you are look, this Twiggy...



You get the picture now? Well, if not, here it is...


Quite an aerial though eh?

What to feed them on then? The clue is in the name of 'Convolvulus'. But what exactly is convolvulus? It's this...


The gardeners enemy: good old-fashioned bindweed. Should be easy enough to find plenty of bindweed? Maybe so, although it is getting quite late in our year to find any that is still growing and green. Then there is the little matter of me looking like a right plonker gathering the one weed that everybody else seems to hate. No matter, most folk around here think I am retarded anyway! Being spotted laying in wet grass, or photographing what looked like (and was) a cow pat...that kind of thing, hasn't helped my cause. 

And so it was that I went out and scored my bag of weed to feed to the hungry caterpillars. They appreciated my offering and probably gave my efforts short shrift as they devoured it. It wasn't long before they began to moult and look like this...


It is a good thing that these are hungry little blighters, because, once cut, bindweed soon wilts like a flower without sun, or a woman without love. By the time of the next moult, they were looking different again...

  

Oh yes! They were now entering their 'new-wave' period: they even acquired 'Adam Ant' face stripes. Some of them moved on further, to what I am going to call the 'Buster Bloodvessel' period. You know the one - the chubby chappy from Bad Manners... 


                          

I don't usually add YouTube videos in the midst of an update for fear you might not return to the remainder of my writing, however, you are reading this right, so you must still be here. Why is there nothing as silly as this in today's music, who dumbed it down?

Where were we? Oh yes, they were starting to get a bit portly themselves...


It was at about this time that the difference between the fastest growing larvae and the slowest became quite apparent. In fact, prior to the smaller ones moulting again, the large green ones had already dug into the soil to pupate. Right before this happened, I measure one: it was 75mm long...



When they did eventually moult, something amazing happened: they changed from green to almost black...

Just completing a moult

Free from the moult

A few hours later and they looked like this (apologies, I have run out of music genre analogies)...


And finally this...



And that just about brings us up to date. There are two of these blackish caterpillars still eating, but I am expecting them to pupate at any time. Will I get any adult moths emerge come spring? Certainly hope to. 







Friday, October 13, 2017

Moon or Luna?



As much as I am enjoying sitting here listening to a bit of Bob Dylan on the iPod, sooner or later, one of us must know (a little clue to the song there) that it's time to knuckle down and write up another blog entry. Just before we get to the subject matter of this update, a question: what do you think is the significance of this next photo?

Well according to the BBC, who recently broadcast a programme about marbles in which presenters showed how a marble was held by the crooked index finger and flicked by the thumb, "this is where the phrase 'knuckle down' came from". 

Let's get to it then: let's talk about caterpillars...
Actually, these are not strictly caterpillars, but larvae: still, carry on John, nobody will have noticed. 

I recently obtained some early instar Actias selene (Indian Moon-moth) larvae. These would be fantastic to observe I thought, and as they seem to like a wide variety of food-plants, many of which I could obtain easily, would be a safe bet. I had a care-sheet from the Amateur Entomologists Society that stated the preferred food-plants:

The caterpillars will feed on a variety of plants, including:-
  • Walnut
  • Apple
  • Hawthorn
  • Cherry
  • Cherry Plum
  • Willow
  • Hibiscus
  • Rhododendron (Rhodendron ponticum)
  • Holm or evergreen oak (Quercus ilex)
On arrival I treated them all to a mix of walnut, apple, cherry, willow and rhododendron, and waited to see which they preferred. None of them was the answer! I added hawthorn and a couple of the larvae seemed to take to it but weren't eating very much and soon began wandering off in search of something better.

This is how most looked when they arrived...



The following day I was starting to think I had made a mistake taking these on as they were definitely not feeding. Then I did a bit of detective work and found that they will also use liquidamber, or sweet gum. 

Where could I acquire sweet gum though? Any ideas? Nor me! Hang on though...isn't eucalyptus a gum tree? That was rhetorical of course, because we  already know the answer . Just need to find some now. Hmmm... might be a problem. 

I pounded the streets, but that did no good and so I repaired them and moved on. I racked my brain...but even putting it on the rack had no effect, I couldn't recall where, or indeed, if, I had seen any locally. I decided the only thing to do was to have a drive around looking for some. My salvation came in St. Michael's near Tenterden, when I spotted this tree outside a house, beside the local garage...


I rang the doorbell. "Hi" said the guy who answered, only half interested as he browsed his phone. "This is gonna sound like a strange request" I said. "try me" he replied, still not looking up from his phone. "Could I possibly steal a few sprigs of your eucalyptus tree?" Finally! his interest had piqued. With a half-smile, he said "Take the whole tree if ya like". Thanking him, I felt I owed an explanation: although, he didn't seem at all interested in knowing my reasons. I mumbled something about caterpillars as he turned and shut the door and I cut myself some eucalyptus.

Success! In fact, a great success. All but a couple were eating like there was no tomorrow and the remainder soon joined in.

It was September 16th when I acquired the caterpillars and by the end of the 17th some were already moulting...






By the 19th of September, many had moulted and were now shades of green...




Time to separate them into individual containers, as I had read that they can be cannibalistic once they start to mature. They were all looking much healthier now and growing fast. All except for the little runt that is. He was still way behind the others and looked like this...


In fact, this is how it stayed right through until September 26th. It was eating, but not a lot. His/her plight was not helped when on the 19th, it somehow managed to circumnavigate the obstacles I placed at the top of the water jar that contained the food plant, and fell right into the water. I have no idea how long it was there before I rescued it, but I dried it as best I could and assumed that it  had possibly drowned as there was no sign of life. 

However, the next time I checked, it was feeding. A miracle. It did eventually moult and became green like all the others, even though it was now a couple of moults behind the rest, who were quite variable in size and colour but doing much better than the runt...





Freshly moulted 29th Sept.

Freshly moulted 29th Sept.


The largest ones were now really impressive beasts. Those feet are brilliant and once fixed to a leaf or stem, there is no moving them. I had also read that they could be aggressive, gnashing their mandibles and swiveling their heads round if threatened, but I had no problems and didn't find any displaying those traits.

October 7th saw my first completed cocoon...


Today (Oct 13th) most have now pupated and I have just three with a bit more growing to do. Now I have to wait and see if any adult moths emerge in around a month's time, or whether they will overwinter and eclose come spring 2018.



Tuesday, October 03, 2017

I'm not really a spider, honest...


As I sit here, wiping the sleep from my eyes, trying to spark my weary brain to action, it's about 192 hours since I last did this. Incidentally, 192 hours is according to a survey conducted by the Express newspaper, the amount of time we all waste per year. That includes at 31 per cent, waiting for slow computers to boot-up.

That French geezer who wrote a bit himself, Victor Hugo once said "Short as life is, we make it shorter by the careless waste of time". He also said "Nothing is more powerful than an idea whose time has come" and I have an idea, and so...


Much to my surprise, my Large White butterflies have started emerging. I have some caterpillars in my studio too (more of that in a future update) and I guess that the temperature I am keeping those at was just a tad too hot for the chrysalises. I suspected a few might be close to eclosing when I spotted the one in the photograph below. The wing spots are already quite distinctive...   



Isn't it annoying how mobile phones rule us! Not only alerting us to every minutia of our lives, but demanding we pick them up to answer immediately. I had been observing this chrysalis for at least a couple of hours, hoping to catch the moment it metamorphosed, when my phone summoned me with a knock, knock. I was distracted for no more than two minutes, when I turned back, it was already half way out! 

Oh well, here it is anyway, at least I got to photo it...



I determined that it wouldn't happen again and so I removed the temptation by leaving my phone in the house whilst I watched another for signs of new life. This time I did better. Not perfect, but better. I could have done with being a little further away really, so that it was still all in shot but at least I get to share what I recorded here.

Watch for the point at about 0:49 where the meconium is expelled. Meconium is the reddish fluid that butterflies expel when they emerge from their chrysalises. It’s a waste product left over from metamorphosis. Also right at the end, it struggles to free one wing from the empty casing...




And then a short video showing it expanding its wings...




Finally a shot of it resting before being released...



I think that the four, yes four have now emerged, were all females. Could that be significant? The other thing that struck me was that I had two colourways of these and it is the green ones that are left: not a single green one eclosed.

I wasn't able to release the first to emerge, the weather was just not good enough. I kept them inside my studio in the garden and allowed them to fly free overnight if they wished. I also provided a sugar-water drink and a sprig of Buddleia should they want to feed.

Luckily the weather the following day was much better, as were temperatures, and so I was able to release them all and watch them fly off. Was it just coincidence I wonder that they all flew to the South East of the garden? 



Something a little different to complete this blog-update. I recently submitted 2 pieces of work for publication, the idea being that it gave the publishers a choice between the two. Having chosen, it left me wondering what to do with the one not chosen and so I thought, why not use it here, rather than leave it unread and unused.

Here it is then...

“The ghost of a spider” 



It was January of 1963 and although we didn’t realise it at the time, we were experiencing what would become the coldest British winter since records began. At Herne Bay, the sea froze for a mile out from the shore: it also froze inland in places, removing the last chance of food for many inland water birds.
At home it was mightily cold too, with temperatures indoors only marginally above those outdoors in the snow.

 Central heating had been used in some select homes since the mid-1800s but it wasn’t for the likes of we plebs. Memory tells me that the house was heated on the ground floor by an open fire, and a Rayburn cast-iron range cooker; upstairs there was no heat source whatsoever, nothing to prevent the frost from forming on the inside of the windows, as it often would in wintertime. Even so, on this particular night I was anticipating bedtime nicely. My pyjamas had been warming on the towel rail at the front of the cooker, ready for me to climb into after ‘my turn’ in the bath, and the stone hot water bottle was already airing my bed. Best of all, dad who was a bit of a Jack-of-all-trades, had installed his latest creation, a set of bunk beds (I shared with my brother) and tonight was to be the inaugural sleep on my choice of the top bunk.

 Yet it wasn’t a wholehearted acceptance of bedtime, there were a couple of reservations uppermost in my mind. There was the omnipresent threat of the terrors: nightmares! By the tender age of 12 they had already become a staple of my nights. Then there was ‘The Thing’, the physical embodiment of nightmares. It hung there in the corner of the room, just below the ceiling, taunting me, making eye contact, threatening to invade my already angst-ridden dream-time and who knows what else it might be capable of should I avert my gaze for even a millisecond. Gossamer thin, opaque at a distance, becoming more translucent should I dare to creep closer: ghostly! In fact such was its form that I had christened it ‘the ghost of a spider’. I had already asked mother if she could banish the ghost of a spider from the bedroom, and by association, my dreams, but my request was met with a curt, “You know I hate spiders, ask your father”.

 I plucked up enough courage to broach the subject that same night, right after he’d admonished me for “that racket” he insisted I was making by trying to play ‘Foot Tapper’ on my Stylophone. I tried to explain as best I could that the tune was one of ‘The Shadows’ finest and my rendition was top-notch, and anyway Stylophones wouldn’t be invented until 1967. “Surrealism isn’t even your prime peculiarity” was his retort; followed by “get yourself off to bed and let’s hear no more about the ghost of a spider, you are almost an adult now start behaving like one”.

 As I ascended the wooden ladder of gloom to my lofty berth, I determined to sleep at the foot-end of the bed. That way the ghost of a spider would at least have to travel a fair way before it could nosedive on its silken thread, pausing only when we were eye to eye, to eye, to eye, to eye to… scare the living B-Jesus out of me. I slithered under the covers as best I could, my chilblains stung as my toes found the water bottle, covering my head with a pillow I drifted off into the best night’s sleep in a very long time. When daylight pierced a gap in the curtains and drew patterns on the wall through Jack Frost’s graffiti on the windows, there in the corner was the ghost of a spider.

 Wiping the sleep from my eyes I crawled to ‘his end’ of the bed. “Today you will become a man” I whispered, almost convincingly to myself. I raised myself up to my full, manly height, all the time trying to avoid stepping on the bottom of my sagging PJs, until me and the ghost of a spider were face to face. Fearlessly, I thrust out my right hand, expecting him to run for his life; instead he remained motionless and so using my first finger and thumb in a pincer movement, I plucked him from his ivory tower. What an anti-climax: he was nothing more than a spider moult. I had been terrorising myself for so long over an inanimate object.


 As with most lessons in life, it had its upside though. Now that I was officially a man, that school bully was about to feel the wrath of my new found confidence. 





If you find yourself anticipating another update 192 hours from now, then apparently to find out exactly when that will be, you need to divide 192 by 24 and then round it down to the nearest whole number, then add that number of days to today's date.