Northern Ireland's Priority Species

Orthosia gracilis – powdered quaker

Orthosia gracilis

Orthosia gracilis (Denis & Schiff., 1775)
Family: Noctuidae

This is a medium-sized, normally creamy coloured, moth which is splashed with many fine black speckles giving it its name. It flies in Spring and is rarely encountered in any numbers although it is fairly widespread. This species has declined by 64% over a 25 year period in the UK but in Northern Ireland there is no evidence of decline.

In brief

  • Widespread in Northern Ireland although there are few records from the north of the country where there is little recording effort
  • The adult flies from late March into May
  • Most likely to be encountered at light
  • A Northern Ireland Priority Species because of declines detected in other parts of the UK where it has undergone a 64% decline over a 25 year period. There is no evidence that the species has exhibited a similar decline in Northern Ireland

Species description
It is a medium-sized, long winged Noctuid moth. The wings are quite pointed, more so than in similar species. The base forewing colour is variable from creamy white through pale grey to brownish but it is consistently sprinkled with black speckles. Other forewing markings are generally obscure apart from a crescent shaped row of faint black dots parallel with the end of the wing.

Life cycle
Single brooded with adults on the wing late March to early May. The caterpillar (May-July) feeds on a variety of plants but especially willows, poplars, blackthorn, bog myrtle and meadowsweet. Early stage caterpillars feed within the spun terminal shoots of the chosen food-plant. It overwinters as a pupa in an underground cocoon.

Similar species
Although there are many superficially similar species none have the combination of relatively long pointed forewings, pale ground colour and black speckling.

How to see this species
The species is commonest in damp habitats such as fens, marshes and wet woodland. Light trapping in such suitable habitat is likely to produce this species

Current status
It is widespread and not uncommon throughout Northern Ireland but with a noticeable lack of records from the north.

Why is this species a priority in Northern Ireland?

  • Listed as a UK Priority Species and therefore on the Northern Ireland Priority List by default
  • Rapid decline (64% over 25 years 1968-2002) assessed using Rothamstead trap data

Threats/Causes of decline
It is thought to be declining in the UK as a result of many factors, including habitat change, pollution and the use of pesticides.

Conservation of this species

Current action
In Northern Ireland there are no specific actions proposed for this species

  • Occurs on many designated sites

Proposed objectives/actions

  • Occurs on many designated sites
  • Increase Rothamstead Trap network to gather data on status
  • Encourage submission of records to the Moth recorder

What you can do

  • Report all moth sightings to the Moth Recorder for Northern Ireland, Andrew Crory, or use the Butterfly Conservation Northern Ireland (BCNI) sightings web page at The BCNI database is managed by CEDaR and these records will then be used to update the Butterflies and Moths of Northern Ireland website.
  • Join Butterfly Conservation. Butterflies and Moths are in serious decline — with your support Butterfly Conservation can take action to reverse this.

Further information

The Butterflies and Moths of Northern Ireland

MothsIreland Website

The state of Britain's moths - an explanation as to how declines have been calculated

Background information on the Rothamstead Trap Surveys

UK Moths Website with an up-to-date distribution map

Skinner, B. (2009). 3rd revised and updated edition. The colour identification guide to the moths of the British Isles. Apollo Books.
Thompson, R. & Nelson, B. (2006). The Butterflies and Moths of Northern Ireland NMNI, Belfast.
Waring, P. & Townsend, M. (2009). 2nd edition. Field Guide to the Moths of Great Britain and Ireland. British Wildlife.

Text written by:
Allen & Mellon