The year 2000 was outstanding for the numbers of migrants visiting the reserve and the following account is an attempt to put the records into context on a local, national and international basis.
Dark Sword-grass Agrostis
ipsilon
Immigrant and transitory resident. A common immigrant which has occurred from March to November and has been noted from most parts of the British Isles. Its distribution in Europe is not known but migrants are common as far north as Denmark and southern FennoScandinavia. It is believed to migrate from north Africa to Europe in the spring and to return in the autumn.
A total of 57 individuals were taken on the reserve from 1 July to 1 November with a maximum of 12 on 30 September.
Pearly Underwing Peridroma
saucia
Immigrant. Has been recorded in every month of the year but is usually most numerous in September and October. It has been noted throughout the British Isles. Cosmopolitan in Western Europe and is possibly resident in the Mediterranean area. Moderately common immigrant to the Netherlands and Denmark. 10 individuals were attracted to light on the reserve between 25 September and 27 October, with a maximum of two on 30 September.
Small Mottled Willow Spodoptera
exigua
Immigrant. Normally appears from mid-July to October but individuals have been recorded as early as February. A regular visitor, reported in most years, usually in small numbers, but sometimes common. Mostly noted in the southern half of Britain. Its range abroad is subtropical and tropical, almost world-wide. It can be an abundant pest of crops. In Europe it is common but possibly only as an immigrant. A single was caught on the night of 7 September and was a new reserve record.
Scarce Bordered Straw Heliothis
armigera
Immigrant. Recorded in virtually every year in southern Britain and increasingly reported inland. It is a tropical and subtropical species and in Western Europe it is resident in the Azores, Canary Islands, Madeira and generally in the Mediterranean region, becoming scarcer further northwards. On 2 October the first record for the reserve was obtained and this coincided with a large influx along the south coast.
Convolvulus Hawk-moth Agrius
convolvuli
Immigrant. It is seen in most years, sometimes in large numbers. It appears from mid-summer to mid-autumn and has been notes from most parts of the British Isles. It occurs throughout most of Eurasia, Africa and the Pacific. This species was a complete surprise when found in Trap 1 on 25 September. It was in a very worn condition with half of its right antennae missing but, never-the-less a welcome addition to the reserve list.
The Vestal Rhodometra sacraria
Immigrant. A regular visitor to southern England with varying numbers almost annually. It has been known to breed in this country, and abroad it is widely distributed in southern Europe and North Africa. Three individuals were taken during the season; the first on 20 June, the second on 1 September and the third on 25 September. It has occurred annually on the reserve.
The Gem Orthonama obstipata
Immigrant. Recorded in most years in varying numbers, usually from the southern half of England. Abroad it has an immense range, occurring throughout Europe, Asia, Africa and North and South America. The two individuals taken this year appeared in the traps on 20 June and 12 August.
2000 was a very good year for migrant lepidoptera on the reserve. Although seven species were recorded, with several common species still not on the reserve list, there is obviously a potential for more.
References:
John Heath & A. Maitland Emmet. 1983. The Moths and Butterflies of Britain and Ireland. Volumes 9 and 10. Harley Books.
Bernard Skinner 1985 + 1986. Colour Identification Guide to Moths of the British Isles. Viking.