Friday, 3 May 2019

Early dragonflies and damselflies

The dragonfly season is already under way in the south of the country, although here I still haven't seen any dragonflies and damselflies. It's time to prepare though, as during May, several species emerge from their larval stages and are most likely to be encountered around ponds and wetlands. These are four species worth keeping your eyes open for as you visit suitable sites in and around Hull.
1. Large Red Damselfly, Pyrrhrosoma nymphula
The earliest flying damselfly is usually the distinctive Large Red Damselfly. It emerges from the end of April to early May, flying until late July, and peaking on the 3rd week of May. It has very uncommonly been recorded in the Hull area, even though it has been recorded in the Tickton area east of Beverley and in the eastern fringes of the Wolds near Brantingham.
2. Hairy Dragonfly, Brachytron pratense. Its early flight period (end of April to Early July) helps separate this species from related hawkers. Peaks on the 3rd week of May. This is a recent colonist to East Yorkshire and there is only one record (2018) in the Hull area, but we expect their numbers to steadily increase so it's worth keeping an eye for them. It holds breeding populations in the middle river Hull area (Tophill Low and Leven Canal).
3. Azure Damselfly, Coenagrion puella. Peaks on the 3rd week of May. It can be abundant in suitable habitats, which include small garden ponds, especially if they have abundant marginal vegetation. It's main distinguishing feature from other local blue damselflies is the spur on the side of the thorax. Several locations known in Hull. Males hang onto females while they oviposit and often many pairs oviposit together.
4. Four-spotted Chaser, Libellula quadrimaculata. Long flight period, from end of April to end of August, peaking on early June. It can be dull in flight, without distinctive features, but males are territorial and like to sit in prominent perches overlooking water, where their lovely markings can be appreciated. The dark spots in the middle of each wing are diagnostic. Females oviposit by flicking eggs into the water, while makes guard them at a distance. They are good colonists and there are records from a few Hull locations including Oak Road Lake, Pickering Park and Noddle Hill.

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