Monday, 4 June 2012

We need your dragonfly and damselfly records

The British Dragonfly Society (BDS) is planning a new atlas of British and Irish dragonflies and damselflies for 2013. Though recording across North Wales has intensified since 2000 there are still many gaps in our recording of all species and your observations are greatly needed to help fill these. Please note that this is the last year to contribute to this atlas and I would encourage you to send in your observations before it is too late. I have the task of processing all such records and making sure they go into the national system. A copy of all BDS records for North Wales also goes to COFNOD.

Mating Blue Emperor (Anax imperator).This species
was a rare sighting before the late 1990s when it moved
north and north-west into the region. It is now widespread
and even breeding in the mountain tarns of Snowdonia.
Is this due to climate change?  
Dragonflies and damselflies, which breed in either running or still water depending on species, are under increasing stress from habitat loss and pollution. They are extremely sensitive indicators of water quality as they are also of Climate Change and worldwide there are many changes taking place in their distribution. Nationally, new species are moving north and entering Britain from the continent and, even for the relatively small region of North Wales, several species have extended their ranges to become resident here since around 2000. So it is important to establish just where each species is currently breeding so we can monitor future changes. Your records will also shed light on the phenology of these intriguing insects.

Female Large Red Damsel (Pyrrhosoma nymphula). This 
year the species was observed to emerge on the 6th April 
which was a record for the earliest emergence. 
Is this due to climate change?
Though lively and beautiful, sun-loving dragonflies and damselflies have never been as popular as, say, butterflies and moths but the publication of several new field guides has led to a surge in interest. Currently 35 species have been recorded from North Wales although four of these are occasional migrants from the Continent and are not known to have bred here. They are particularly popular with wildlife photographers as they pose an interesting challenge in technique. As they are very active flying creatures, identifying adult dragonflies can appear daunting but in reality, and with a little practise, it should not prove that difficult if one is patient enough to wait until they settle up. Their colours are sexually dimorphic: males are more brightly and distinctively coloured and the easiest to identify; females are typically cryptically coloured and with some species of damselfly there may be a bewildering array of colour forms. Poorly coloured emergent and immature adults (tenerals) are difficult to identify and are therefore best avoided by beginners.

Male Downy Emerald (Cordulia aenea). Llyn Tecwyn
Isaf is the only known site in North Wales where
this species is known to breed. The larvae live
 amongst the leaf litter of tree-lined lakes.
Are there any other lakes with this species in North Wales?
As regards where to record, I’ve attached a map showing what the state of recording is for each 10 km square across North Wales. This is the resolution that will be used in the new BDS atlas. The numbers refer to the potentially ‘missing’ species for each square. The squares with red numbers are my target areas. But records from anywhere are most welcome as we also need to understand the distribution at more detailed scales and it is hoped to publish a more detailed account for North Wales at a later date. The actual ‘missing’ species are shown in the attached Excel chart with the use of abbreviations.
As regards what details to give, the minimum criteria would be date seen, location name, 6- or (better) 8-figure grid reference and the name of the species seen (with photos if possible to confirm identification – quality is not that important). Of more help in recording would be numbers seen of each stage: adults (males and females), copulation pairs (including tandem pairs), oviposition (egg-laying), exuviae (larval skins), emergent adults. The latter two stages are really the most important as they indicate positively that the species has bred successfully at the water body. The best way of estimating numbers of each stage is: A = 1, B = 2-5, C = 6-20, D = 21-100, E = 101-500, F = >500.

An image showing the potentially missing species in North Wales can be viewed by clicking here.

Please send the records in anytime (much better late than never!) but if it was a really interesting sighting, for example an indication of a migration underway, a prompt response would allow me to say something in a current ‘North Wales Dragonfly Newsletter’; this is copied onto the Cofnod website. More detailed records are best sent in using Excel format with separate columns for each stage entry. Examples of the way to send records in is provided by the BDS website page: Send records to me at my e-mail address:

Dr Allan Brandon, North Wales Dragonfly Recorder for the British Dragonfly Society. (all images and content from Allan Brandon) 

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