Saturday, 19 December 2015

The very hungry caterpillar, and other lepidoptera...

More wet and windy weeks have passed with little opportunity for getting our into the local patch with my camera, so I thought I'd use this post to reflect on some of the butterflies and moths I've seen (and also not seen) this summer as my outings in the local patch recently have been few and far between, and also to have a look at how some of our most familiar butterflies fared in this year's Big Butterfly count.

Burnet moth acrobatics!!!
Starting with a moth I haven't seen at all this year... 6-spot Burnet moths which appeared to have a good season last summer, with dozens in one small area of meadow in a local country park worryingly I didn't see at all this summer in the same spot. Was it the weather, my timing or perhaps could many of the eggs/larvae have been destroyed in the harsh mow inflicted on the area towards the end of the summer??? I guess I'll never know for sure, but it's obvious to me that just in my lifetime the amount of insect-life has decreased dramatically. I've had the same conversation with friends who (when they stop to think about it) concur that things have changed dramatically from childhood memories, in my case largely the 80s....  

Summertime drives out with my Dad would result in a bug-spattered car windscreen - that's certainly something I don't have to contend with and can only indicate significantly fewer insects. Also an almost complete lack of moths. I can certainly remember a time when streetlights would be buzzing with circling moths, hopelessly attracted to the artificial light. Or slightly scary visits (this was when I was very young!) to any shed/garage or other outbuilding when the simple flick of a switch would be a clarion call for every large flappy moth in the vicinity to come and join me. These days I suspect I could leave every window wide open at night with the inside lights on and be lucky to see even one or two of the larger 'macro' moths. They're not good signs, and I live in hope that we can turn things around before its too late, assuming that it isn't already. (I have tried to avoid using blog posts as a place to rant but the indifference of successive governments to the plight of wildlife and the environment (particularly the current bunch) has been a constant source of exasperation.)

6 spot Burnet on Selfheal



On a more positive note, a lovely first for me this year was a Gold Spot moth, not one I'd previously heard of or seen, but a spectacular insect which lives up to its name with metallic golden spots on its wings (I'm not sure the photo really does the metallic gold justice, but it really was like spots of gold leaf on the wings).

Gold spot moth


Ringlets are a species of butterfly that are nationally fairly common, but locally I have always found fairly scarce. An exception to this is at CWT Swettenham meadows - a reserve which is well known as a wonderful spot for butterflies and where Ringlets appear to have had a very good year. (According to the 2015 Big butterfly count results, their numbers are up 75% on last year.) I first noticed this pair in flight - as they were already paired (presumably I had unwittingly disturbed them), I initially thought it was one giant insect, but tracked them down having settled on a large leaf, doing their bit to ensure the thriving colony at Swettenham meadows continues for another year...

Making more Ringlets...



Red Admiral butterflies were less prevalent overall in the Big Butterfly count this year  in comparison to 2014, declining by 28% however locally again they appeared fairly frequently, including in our garden counts. Only a small proportion of these butterflies are considered resident - adults may try to hibernate over winter, and there is evidence that particularly in southern areas they are doing so successfully, however most of the butterflies we see are migrants which, quite incredibly, have flown here from central Europe. Consequently their numbers can vary considerably from year to year .

The unmistakable Red Admiral on Green Alkanet flowers
Large Skippers, (considering their tiny size, 'large' never really feels an appropriate description) did well in the Butterfly count, increasing by 24% from last year despite quite a lot of poor weather. They were out in force in their favourite areas of long grasses locally as soon as the sun shone, as were the ever so slightly smaller 'Small' Skippers. Unfortunately these are the only kinds of Skippers I am likely to see in my local patch however they are two of my favourite insects. Apart from their tiny size and inherent cuteness, they are also quite laid-back, making them great to photograph. (The one happily sat on my thumb in my profile image demonstrating how nonchalent they can be...)   

Large Skipper on Soft rush



Gatekeepers along with Meadow Browns were the most widely recorded 'brown' butterflies this year in the Big Butterfly Count in 1st and 3rd places respectively, the former were also the most numerous butterfly seen in our garden. Gatekeepers are superficially similar to Meadow Browns and typically found in the same grassy habitats but they are smaller and more brightly coloured with white spots on their underwings.

Gatekeeper

Meadow Brown

Small Coppers had decreased in prevalence by 28% compared with last year in the count - they are so tiny they are easy to miss, though I did see a very small number this year, again at Swettenham meadows. 

Small Copper (taken 2014)
My most recent butterfly sighting, was the fleeting glimpse of the distinctive yellow wings of a male Brimstone butterfly. This was right at the end of November, though as one of our native butterflies that successfully hibernates as an adult through the summer, they can be occasionally seen even in winter months when the weather is very mild. 

Brimstone (taken in the summer)

Elephant hawkmoth caterpillar
One of my lepidoptera highlights of the year however was found by my husband just in our garden. It started with the mystery of what was eating a new climbing fuchia... Large chunks were disappearing but no culprit had been found.... until one weekend when my husband called through the house with a sense of urgency in his voice... "JAN.... there's something you need to see here..." Grabbing the camera to see what the fuss was about I was amazed to see that he had found what I instantly recognised as an [impressively large] Elephant hawkmoth caterpillar, the size of my index finger. Having been caught in action, the caterpillar performed striking actions like a tiny snake (making me jump even though I knew they could do this if feeling threatened!). 

In the top photo, you can just make out two of the caterpillar's 'spiracles'. These are openings through which air diffuses into a series of tubes called trachea which make up an insects' breathing system supplying organs directly with air.     

Sensing that this caterpillar might need to be found a new home, I found out about their natural foodplants - whereas they would usually feed on Rosebay willlowherb and bedstraw, they are also known for having a bit of a thing for garden fuschias. Recalling how my Mum had reared caterpillars found in the garden so as a child I could see their lifecycle, I thought this would be an ideal opportunity to do the same for my own kids. Rosebay willowherb stems were duly gathered and caterpillar and alternative food supply were relocated to a mesh pop-up insect 'cage' (which had been one of those random purchases by my youngest at his school fair). It was only a couple of days before s/he loosely spun together a couple of leaves and settled to pupate in the bottom of the enclosure. Hawkmoth caterpillars wait out the winter in this stage so has been moved to our cold garage. Come the spring she will be brought back into the warmth and we will be watching (like nervous parents!) keeping fingers crossed for a successful emergence and the appearance of arguably one of the UK's most spectacular insects in their vibrant colours of pink and green. To be continued...


Below are the 2015 results for the 20 target butterfly and moth species taken from the Big Butterfly count website.




Abundance % change from 2014
1 Gatekeeper 106995 17
2 Large White 83042 46
3 Meadow Brown 76713 16
4 Small White 72483 -3
5 Peacock 42754 -61
6 Small Tortoiseshell 31322 -57
7 Ringlet 27604 75
8 Red Admiral 21027 -28
9 Comma 18765 42
10 Common Blue 17932 -12
11 Green-veined White 14437 -42
12 Speckled Wood 12342 -25
13 Large Skipper 11198 24
14 Holly Blue 10334 151
15 Six-spot Burnet 9448 2
16 Marbled White 8071 52
17 Painted Lady 7416 28
18 Brimstone 6075 18
19 Small Copper 4395 -28
20 Silver Y 1912 92

8 comments:

  1. Hi Jan, thanks for pointing out the BBC awards - I wasn't aware of that. Congratulations to you as well on being 'highly commended', you deserve it - its a beautiful blog. These butterfly photos are fabulous.

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    1. Thanks very much Phil. :) I'd hoped to get up to Arnside Knott this year to try and photograph some of the less common butterflies that we don't see around here but between work and weather didn't manage it - maybe next year!

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    2. btw I thought I'd give the trap a go last night (the very mild weather has produced some interesting things for some people) - wasn't expecting much and that's exactly what I got - moths:0, slugs:3, weevil:1

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    3. I've wondered about giving moth trapping a try though I honestly doubt I would catch very much here (you never know until you try I suppose). At least slugs are doing ok! The general scarcity of butterflies and moths in the warmer months is a worry though.

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    4. What is about your site that makes you think you wouldn't catch much? You'll catch, at least, something almost anywhere - my trap is in what would be considered a poor site in that it's tucked into a corner so only a 90 degree beam angle, but I get enough. I'm quite glad I don't get the massive catches (400-500 some nights) that some people get with mercury vapour lights and 360 degrees. You can get overwhelemed, ID-ing them all, but also the logistics and time required to 'process' them.

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    5. I'd probably just set up in the garden which in theory should be quite good - loads of mature shrubs and hedges, lots of flowers, no insecticides etc. I just don't notice many moths at all around outside lights, or at the windows when our indoor lights are on at night. It would be good to see what is about though - have you got any recommendations for a starter trap?

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    6. The majority of moth-ers just trap in their gardens -I do. I think you'll catch plenty - another consideration though is number of competing lights in the area. One like mine would make a good starter I think- less powerful than a mercury vapour 'skinner' but fine for me. I put mine in a corner so as not to bother neighbours.
      http://www.watdon.co.uk/acatalog/E7592-40W-heath-trap-mains-operated.html#SID=10

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    7. Brilliant thanks for that - I will look into it. (It might make a good late Christmas present!)

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