I have finally gone through my records from 2014-2021 to tot
up catch by species for each year. Apart from being able to see some trends the
other stand out insight was how far out my impression of how common certain species
had been in previous years.
In particular I over-estimated previous catches of some of
the species which to me were more iconic. So things like Privet Hawk and
Buff-tip have been more or less stable rather than in decline as I’d believed
before I went back to do the yearly counts.
Looking at previous years I can also see that some species
that weren’t common or absent in 2021, had varied also in the past. I’ve also
excluded from the analysis those species that were in low numbers to start
with.
The ones that look as if there actually are trends are:
Heart & Dart 2021 only 31. (2020 = 179, 2019 = 272)
Treble-lines seems to have quadrupled in numbers in the last
3 years.
Small Elephant Hawk seems to be increasing in the last few
years.
Small Square-spot 2014-2017 averaged 20 a year. There were
then none 2018-2020. 10 appeared in 2021.
Buff Arches, average 2014-2018 10 per year, since average is
only 1 a year.
Riband Wave has consistently declined year by year, 2014 =
64, 2021 = 25.
Flounced Rustic numbers more than doubled for 2020-2021.
Dot Moth has declined, 2014 = 34, then numbers went down,
20219 & 2020 none, 2021 = 2.
White-point, as might be expected has increased. From 2014 =
3 to 2020 = 27 this was more or less a consistent increase. 2021 was 118!
Common Wainscot was more or less stable 2014-2016 at av 50
per year, 2017-2019 it was consistent at 190 per year, 2020 hit 546 and 2021 it
was 894. That means it over took Large Yellow Underwing numbers for the first
time.
Large Yellow Underwing seems to have declined. Until 2017
the average was around 1,200 per year (2015 went up to at 1,627). 2018 = 832, 2019
= 634, 2020 = 732 and 2021 = 751.
Hebrew Character numbers seem to have halved since 2019,
2021 = 28.
Straw Underwing seems to be increasing, average 3 a year
20214-2017, 2018 = 13, 2019 = 6, 2020 =42, 2021 = 20.
Setaceous Hebrew Character seems to go up and down, lowest
was 75 in 2014, 511 in 2018, and 508 in 2021.
Other observations
Tree-lichen beauty arrived in 2019, it’s now continued to
appear since.
Box-tree moth arrived in 2017 and seems to be increasing.
Clifden Nonpareil also appeared in 2017 and has appeared in
ones and twos since.
Dark Arches, Black Rustic, Broad-bordered Yellow Underwing,
Common Quaker seem to be going down, but had increased previously so it looks
as if it might be cyclic.
All of these were caught in a 40 w actinic heath trap. Location consistent and
trapping all nights when the weather was ok. Garsington is a village just
outside of Oxford and we are at nearly 400 feet. The garden is fairly unkempt
with some native herbaceous plants but sadly few trees or bushes. There are
trees in neighbouring gardens and close thickets. Some have been cleared for
development. The village is largely surrounded by arable farmland.
Total species caught over the years is about 550(ish).
