WINE RACE 2016 .. MATTc380 .. TRENT 353 .. BEN 347 ...... Garden species:- Macros 357, Micros 365, Total 722

Tuesday, 10 April 2012

10th April 2012 ... Meaningless minimum temperatures

It is now 19.40 on the 10th April.
The rain has stopped, the temperature is 7 deg and falling rapidly towards a predicted grass frost in the early hours.
This is the forecast for the rest of the week.
The traps will be going on until the temperature falls below "silly" degrees, which should be around midnight-ish.

At the end of March this year, I was well ahead of the 2011 macro species count which I attributed to the much better weather compared to last year, but I have since slipped behind during April, which I thought was probably due to the fact that last April was one of our best months weather-wise.
With that in mind, I figured that I would slip well behind last years running macro moth count as the April long range forecast for this week is for colder average day temps with a risk of frost in the mornings....not good.
Or will I ?
Time for some comparisons....
I have been recording the minimum nightly temperature for the last two years to compare temp/species/numbers ratios, as warmer nights mean more moths...right ? 
Last year in the Biggleswade area, March was a cold month compared to March this year.
In 2011 I had 26 nights with the traps on, the average minimum nightly temperature was 3.8 deg.
This year, March was seeing record daytime temperatures around the UK.
The traps were on for 29 nights but the average minimum night temperature was 3.6 deg....surprisingly lower. 
My recording of MINIMUM night temperature is totally useless and I gain no helpful information mothwise.
It might be better to take temperature readings at dusk and say two more readings at one hour intervals for March.
Maybe in that way some sort of behavioural pattern will emerge.
And maybe barometric pressure and wind speed/direction can also be incorporated along with chill factor and humidity.
The information gleaned from all this would be invaluable....I could determine the good trapping conditions with some accuracy and the nights when not to bother, and save on the electricity bill....................
Or better still...use Sods Law and rely on Pot Luck, with it's unknown highs and lows...way to go !
 But I will still post the min. temp. for my area if only for curiosity value...............  


  1. Hi Trent,

    Glad to see that someone else ponders about the effects the various weather criteria have on our winged friends! Sometimes I get a bit caught up with it and then throw my data down, go and stand in the garden, stick my finger in the air and say "Sod it, I'll trap anyway!"

    Keep up the good work!

    Steve T