Thursday, 24 April 2014

A bit of an experiment....and `Target Aspen`

I had three traps out last night (23/4), two in the garden at Pwll and a `mobile actinic` amongst some aspen thickets east of Burry Port. A fourth actinic did n`t go out, as I ran out of time!
The experiment in the title refers to a comparison made by the placement of two exactly-the-same actinics in the garden, one on the flat roof of a small extension and the other on a seat lower in the garden. One problem with the flat roof site is exactly the same as the problem that Isabel highlights in her posting below, ie in heavy rain, many moths get stuck in surface water making them difficult-to-identify and easy prey for birds (if you`re not up before them!). There`s no really good answer to this problem apart from possibly putting a form of transparent shelter above it or a permeable material (eg an old bed sheet) spread around the immediate area of the trap itself. This `rain problem` is hardly an issue when you trap in natural habitats - I`ve left out actinics overnight in torrential thunderstorms and had really good catches!
The results of my trapping experiment were similar - 14 spp v 17 spp, with the higher figure perhaps surprisingly on my `lower down mid-garden trap`.
The two different trap sites are shown below:

                                         Above: the `mid-garden trap`
                     Above: `visual moth catchment` looking back (south) from the higher roof-top trap

Moths caught at the two Tyrwaun, Pwll traps included `first-for-year` (FFY) puss moth, knot-grass, brimstone moth, muslin moth, whilst there were increasing numbers of swallow prominents and a single frosted green.
                                      Above: a rather unrelaxed puss moth showing its furry legs.
                                         Above: `FFY` knot-grass at Tyrwaun.
                                         Another `FFY` - this time, a male muslin moth.
                                         Above: one of last night`s powdered quakers at Tyrwaun.
The only `away-from-home` site at which I trapped last night was amongst a thicket of aspen, east of Burry Port. I was trying to see if I could catch a lead-coloured drab but failed, either because they are simply not there or perhaps because they were `over`. I caught quite a few early tooth-striped moths and checked them for the aspen-feeding seraphim, but again no luck. I will re-try for the latter in a few weeks` time as well as small chocolate tip later in the season. Amongst the 13 spp at this site was a FFY flame carpet and quite a lot of the micro Grapholita jungiella, whose larvae feed on vetches etc. Given my indifferent photographic skills, I did n`t attempt to take a photo - a good photo can be seen on p51 in Chris Manley`s excellent (and recommended) British Moths & Butterflies: a Photographic Guide.

                                         Above: early tooth-striped.





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