A very unscientific look at 2011 compared with the previous two years threw up some quite interesting statistics. There are obvious drawbacks with such a small data set, and even taking into account 25% more effort through the year, the spread of trapping sites and dates was fairly consistent. The 20 most numerous macro species were, in most cases, considerably more numerous than the average of the previous two years.
There were declines noted in 4 species, Common Quaker and Small Quaker down due to the extremely good numbers of Spring 2010; Large Yellow Underwing was well down on 2010, but similar to 2009, as was Mottled Beauty which was only fractionally down on the average.
The next few slight increases may be accounted for mainly by the extra effort, and then there are some dramatic figures, more than doubling for Brown Silver-line, Clouded Border and Yellow-tail. Next, Flame Shoulder, Common Footman, Dark Arches and in particular Smoky Wainscot and July Highflyer increased greatly, and the amazing numbers of Four-dotted Footman was also the third most common species which in itself is remarkable.
Taxon | Vernacular | 2011 | 2010 | 2009 | Ave 2009/10 | % change |
Orthosia cerasi | Common Quaker | 272 | 530 | 135 | 333 | -18.2 |
Noctua pronuba | Large Yellow Underwing | 190 | 283 | 180 | 232 | -17.9 |
Orthosia cruda | Small Quaker | 107 | 201 | 48 | 125 | -14.1 |
Alcis repandata | Mottled Beauty | 217 | 133 | 303 | 218 | -0.5 |
Campaea margaritata | Light Emerald | 122 | 39 | 187 | 113 | 8.0 |
Pheosia gnoma | Lesser Swallow Prominent | 116 | 71 | 99 | 85 | 36.5 |
Orthosia incerta | Clouded Drab | 188 | 223 | 51 | 137 | 37.2 |
Conistra vaccinii | Chestnut | 107 | 112 | 22 | 67 | 59.7 |
Xanthorhoe montanata | Silver-ground Carpet | 142 | 81 | 69 | 75 | 89.3 |
Idaea aversata | Riband Wave | 124 | 39 | 89 | 64 | 93.8 |
Petrophora chlorosata | Brown Silver-line | 175 | 112 | 62 | 87 | 101.1 |
Oligia strigilis agg. | Marbled Minor agg. | 112 | 69 | 39 | 54 | 107.4 |
Euproctis similis | Yellow-tail | 131 | 38 | 88 | 63 | 107.9 |
Lomaspilis marginata | Clouded Border | 194 | 46 | 86 | 66 | 193.9 |
Ochropleura plecta | Flame Shoulder | 136 | 39 | 35 | 37 | 267.6 |
Eilema lurideola | Common Footman | 562 | 119 | 142 | 131 | 330.7 |
Apamea monoglypha | Dark Arches | 109 | 42 | 7 | 25 | 344.9 |
Mythimna impura | Smoky Wainscot | 122 | 24 | 22 | 23 | 430.4 |
Hydriomena furcata | July Highflyer | 220 | 23 | 33 | 28 | 685.7 |
Cybosia mesomella | Four-dotted Footman | 258 | 0 | 13 | 7 | 3869.2 |
Four-dotted Footman |
The Four-dotted Footman trapped in 2011 were all in the Pilmoor area:
Pilmoor wood SE | SE4672 | 1 | 07-Jun-11 | |
Pilmoor wood NE | SE4673 | 1 | 07-Jun-11 | |
Low Wood (E), Pilmoor | SE4772 | 5 | 14-Jun-11 | |
Sessay Wood, Pilmoor | SE4773 | 14 | 14-Jun-11 | |
Pilmoor wood SE | SE4672 | 1 dead | 29-Jun-11 | |
Sessay Wood, Pilmoor | SE4773 | 82 | 02-Jul-11 | |
Low Wood (E), Pilmoor | SE4772 | 21 | 02-Jul-11 | |
Pilmoor wood NE | SE4673 | 84 | 10-Jul-11 | |
Sessay Wood, Pilmoor | SE4773 | 42 | 14-Jul-11 | |
Pilmoor wood SE | SE4672 | 7 | 21-Jul-11 |
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