Moth Report 1999 By Jane Hayden
Moth recording was much less intensive than in 1998, due to the lack of an experienced person throughout the season. However, trapping was carried out nightly from mid June until the end of August, with some trapping during April and September. Day flying species were recorded throughout the season. A total of 107 species of macro-moths were recorded during 1999, of which only one (Square-spotted clay, Xestia rhomboidea) was new to the island. Of the micro-moth species recorded during the year, three were new to the island: Choreutis myllerana, Stigmalla plagicolella and Argyresthis albistria. Skomer also had two new butterflies this year, Holly Blue (Celastrina argiolus) and Monarch (Danaus plexippus). The Skomer lepidoptera list now stands at 353.
Immigrants and other unusual moth species from Skomer (not mentioned above) are recorded below (all records refer to adults trapped at light unless stated):
Diamond-back moth P. xylostella Just 3 records on 10 June, 30 June and 12 August.
Rusty-dot Pearl U. ferrugalis A poor year with only a single record on 3 July.
Rush Veneer N. Noctuella Only 2 singles, on 18 July and 20 September
Spruce carpet T. britannica One on 22 August was the second record for the island.
Shaded Broad-bar S. chenopodiata One by day on 29 August is the first record for the island since 1946.
Convolvulus Hawk-moth A. convolvuli One by day on 30 September was the only record.
Poplar Hawk-moth L. populi One on 17 June was the third record for the island.
Hummingbird Hawk-moth M. stellartarum Five singles, between 25 June and 7 July. The fifth was on 2 April, the earliest on Skomer by far.
Dark Sword-grass A. ipsilon A total of 287 from 2 April to 20 September. Max. 84 on 22 August.
Pearly Underwing P. saucia Only 3 records from 23 to 26 September.
The Delicate M. vitellina 2 singles on 22 August and 11 September.
Pale Mottled Willow C. clavipalpis One on 20 September was the second record for the island, the first being in 1974.
Silver Y A. gamma 112 recorded from 26 June to 25 August. Max. 63 on 22 August.
There are also numerous rare or scarce species that breed on the island. All three of the "Notable A" species were re-recorded in 1999, with four records of Barrett's Marbled Coronet Hadena luteago barrettii, five of Devonshire Wainscot Mythomna putrescens and two of Black Banded Polymixis xanthomista. Of the "Notable B" species, Eudonia lineola was trapped on 6 dates (with 12 in the trap on 23 July), and there were a total of 32 Hoary Footman Eilema caniola, 112 Square-spot Dart Euxoa obelisca, 841 Crescent Dart Agrotis trux (the most abundantly trapped moth in 1999, as in 1998), 25 Marbled Green Cryphia muralis and 4 Webb's Wainscot Archanara sparganii.
Butterfly immigration was generally unimpressive, the highlights being the Holly Blue in May, a single Clouded Yellow Colias croceus on 2 September, and the Monarch on 30 September.
Many thanks to Elizabeth Wilberforce, John Talbot, Norman Lowe and Chris Lowe for contributing to these records. Thanks especially to Norman Lowe for identification of most of the micro-moths.