Odonata survey training event adds Red-eyed Damselfly to Crossness roster

Some ten plus Red-eyed damselfly (Erythromma najas) seen on the Southern Marsh at Crossness by attendees at the June 3rd Dragonfly and Damselfly identification workshop led by London Wildlife Trust’s David Courtneidge, brings the total number of species recorded at the reserve to 18, two more than the next best site in the Borough which is Foots Cray Meadows with 16.

Male Red-eyed Damselfly at Crossness Southern Marsh, 3/6/17 – a new site record. (Photo: Karen Sutton)

Red-eyed Damselfly has been present in Bexley since at least 2009, and has now been recorded at Danson Park, Lamorbey and FCM, also at Tump 53 in Thamesmead, so its appearance at Crossness was expected, and it may have simply been overlooked to date. The site is probably also the best-placed in the Borough to be colonised by other ‘new’ species now moving up the Thames estuary. 

Four people attended the event, along with David and Reserve Manager Karen Sutton.  It started off at the Thamesmead Football Club at 10:00 with a presentation on key ID features. The group had lunch and made its way to Southern Marsh at 12:30, on what was lovely sunny Saturday.

The survey group in action. (Photo: Karen Sutton)

Six species were recorded:

5+ male Emperor dragonfly (Anax imperator) which were seen patrolling along the lake edges, 2 four spotted chaser (Libellula quadrimaculata), 1 male black tailed skimmer (Orthetrum cancellatum), 10+ red-eyed damselfly (Erythromma najas),           20+ blue tailed damselfly (Ischnura elegans) and 50+ azure damselfly (Coenagrion puella). Efforts were concentrated on the Wetland Field and Saline Field water bodies, and all the vegetation in between the two. The Saline Field didn’t turn up any species that we hadn’t already recorded (Emperor dragonflies and Azure and Blue-tailed Damselflies), but the Wetland Field was where the Red-eyed Damselflies and Four-spotted Chasers were seen.

Four-spotted Chaser at Crossness. (Photo: Karen Sutton)

Mating Azure Damselflies, Crossness Southern Marsh. (Photo: Karen Sutton)

David will be doing more surveys in Bexley and it’s not too late to get involved. A survey calendar will be published shortly and anyone is welcome to join in. Meantime contact David at <dcourtneidge@wildlondon.org.uk> if you are interested.

Info for this post provided by David Courtneidge, Karen Sutton and Chris Rose.