Following on from Raymond’s message, thought I’d have a look at my results for the same period. I have run lights for around 20 years at 2 regular sites that haven’t changed, supplemented with additional trapping in the summer at other spots on the site to cover different habitats.
Here are my species totals:
2012 – 649
2013 – 746
2014 – 710
2015 – 738
2016 – 689 (with just a small number to add once confirmed).
Looking at these figures, 2016 looks just slightly below average here. 2012 was a cold wet summer so no surprise the total is the worst for the period. I don’t think this tells the whole story though, so now here is a list of the total number of moths caught for the same period:
2012 – 27876
2013 – 31477
2014 – 31423
2015 – 35114
2016 – 27471
Again, it can be seen that 2012 was poor, but then 2016 was slightly worse for numbers compared to a more average figure of over 3000 here. I think also the number of trap nights will add more to the picture, as I don’t trap every night but just pick the better ones.
I trapped on 124 nights in 2016 and have just compared this to 2015 when I trapped on 113 nights. I was away on holiday for a week in May and June plus 10 days in July in 2016 so I know I put in more effort once I returned in July and also in the autumn when migration was taking place. But even putting in this extra effort didn’t boost numbers of moths trapped. I do go on holiday every summer for a few weeks so I don’t think me being absent would make a lot of difference to the 2016 totals (especially in May and June that year).
My feeling on 2016 was that it wasn’t too bad for the variety of moths seen but certainly the actual numbers trapped were down, especially so with the common moths like the underwings. The first 6 months were terrible, with very poor numbers of quakers and the only moth in numbers being the migrant Plutella xylostella. I put the blame mainly on the mild winter. At least this year we have been getting cold snaps so it will be interesting to see if things are better than 2016.
Anyone else able to add information on their trap results? Be good to see some figures from other parts of Suffolk.
Neil
Yes. Interesting Neil. I would tend to agree on the total numbers of moths but unfortunately I don’t have figures to prove it. This was certainly the case for the poor spring but I am not so sure for later in the year which although late did improve on the numbers caught. It is quite remarkable that the actual number of species we have each recorded is so very similar except for 2016. However we catch different species. I have looked up the number of times I have trapped each year. Bearing in mind that 2012 was not so organised as the other years and with different and sometimes only one trap.
2012 – 680 species 169 nights
2013 – 745 species 112 nights
2014 – 726 species 102 nights
2015 – 738 species 119 nights
2016 – 751 species 109 nights
This tends to suggest either I am atypical for 2016 or your catches are down owing to some environmental variation in your locality. While looking through the temporal variation of nights trapped the variation was enormous despite similar annual totals. Overall remarkably static data.