Thursday, 6 June 2013

A party political broadcast on behalf of moths

Moth numbers are undoubtably depressed. Back garden mothing has taken on a whole new ball game, with vacant egg-boxes and empty pill-boxes being the normal state of affairs. At the moment I'm not even bothering - the night's are decidedly chilly and those brave lepidopterists that are switching on regardless are not being rewarded for their efforts. I thought I'd look back twenty years to see what sort of numbers I was able to record then - all counts being of macro moths coming to a single 125W MV trap in my suburban Surrey garden. I stopped counting every moth in 1994. There are times when I wish that I had continued to do so, as I would now hold data for 26 continuous years from the garden.

The following represent the highest count gathered from the first 10 days of June:

1990 - June 9th: 435 of 38 species
1991 - June 7th : 65 of 25 species
1992 - June 7th: 225 of 39 species
1993 - June 8th: 253 of 39 species

As can be seen, 1991 was a cool and dull spring. Most of these counts were not un-representitive of the ten-day period that I looked at. Not terribly scientific, but a picture can be built.

Early June 1996 was exciting. There was a massive arrival of migrants, with Painted Lady and Silver Y to the fore (I had 50 and 2,000 respectively in the local park one afternoon). My garden MV produced a Gem, nine Bordered Straws, plenty of noctuella, xylostella and ferrugalis. Not bad for a site 50 miles away from the sea. I didn't do full counts at the time, but the numbers were high.

It is getting worrying. How many years have moth numbers been falling now - is it four or five? It is most probably more noticeable in town gardens, although some coastal trappers are experiencing similar low numbers. I have read that populations can be cyclical, but are we now reaping what us humans have sown?

I've often thought that, in a hundred years time, man will look back on the mid and late 20th century, shaking their heads, and mutter "Did they not realise what they were doing to themselves and the wildlife of the planet?" Maybe some of us did, but those that wielded the power were not interested if it got in the way of personal short-term gain.

Iron Prominent - catch it while you can...

2 comments:

  1. Ditto Birds,ditto Butterflies.....

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  2. Yes Laurence, it's all a bit grim, isn't it

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