Based on the article “Damselflies and Dragonflies (Odonata)”, by Roy Beddard, in Birds of Brent Reservoir: The Natural History of the Welsh Harp
To date, 15 species within the order Odonata have been recorded at the Welsh Harp — six damselflies (suborder Zygoptera) and nine dragonflies (suborder Anisoptera). All are listed below, with an indication of their status and the time of year when they are most likely to be seen.
- Banded Demoiselle Calopteryx splendens
Very rare (only three records). Mid-May to early September.
- Azure Damselfly Coenagrion puella
Widespread. Common breeder. Late May to late August.
- Common Blue Damselfly Enallagma cyathigerum
Widespread. Very common breeder. Late May to September.
- Small Red-eyed Damselfly Erythromma viridulum
Very rare (unknown in the UK before 1999). The only record is of 12–15 in the northern reservoir in August 2007.
- Blue-tailed Damselfly Ischnura elegans
Common breeder. Late May to late August.
- Large Red Damselfly Pyrrhosoma nymphula
Previously very rare but becoming more common. Late May to early June.
- Southern Hawker Aeshna cyanea
Scarce but annual. Breeds in very small numbers. June to early October.
- Brown Hawker Aeshna grandis
Regular breeder in small numbers. June to early October.
- Migrant Hawker Aeshna mixta
Common and widespread breeder. Late July to October.
- Emperor Anax imperator
Widespread regular breeder in small numbers. Late May to late August.
- Broad-bodied Chaser Libellula depressa
Regular breeder in small numbers. Late May to early August.
- Black-tailed Skimmer Orthetrum cancellatum
Recent colonist. Regular breeder in small numbers. July to August.
- Red-veined Darter Sympetrum fonscolombei
The only record for this species is a male seen on 24 May 2009.
- Ruddy Darter Sympetrum sanguineum
Localised. Possibly a regular breeder. Early July to October.
- Common Darter Sympetrum striolatum
Widespread, common breeder. Late June to October
Beddard R. (2002) “Damselflies and Dragonflies (Odonata)”, in Birds of Brent Reservoir: The Natural History of the Welsh Harp (eds L. Batten, R. Beddard, J. Colmans, A. Self). London: Welsh Harp Conservation Group.