Variable Damselfly Survey

 

The British Dragonfly Society is asking you to help us understand the beautiful Variable Damselfly by submitting your sightings.

 

The Variable Damselfly is found in and around well vegetated ditches, canals and ponds, rarely in flowing water habitats. In Britain, Variable Damselfly is scarce and very localised with an extremely patchy distribution, but the species can be abundant at sites where found. Its distribution remains something of an unravelled mystery. There are sites adjacent to current populations which look suitable for the Variable Damselfly but which don’t appear to support it. Is there something the species needs which we are not aware of or are such anomalies down to variations in recording effort at different sites? Reasons remain unclear, indicating a need to better understand the species’ habitat requirements and current distribution.  A further, and rather worrying, aspect of the species distribution is the lack of records over the last 20 years for the Variable Damselfly in previously known locations. This suggests a contraction in the species’ range, with implications for its conservation status. Alternatively, this may, again, simply reflect changes in recording effort in different locations over time.

 

Map showing Variable Damselfly distribution. From the Atlas of Dragonflies in Britain and Ireland, courtesy of the BRC.

 

The Variable Damselfly is a tricky species to identify; it is not called variable for nothing! The Variable Damselfly is a known as a Coenagrion damselfly, a group of closely related damselflies which are strikingly similar in appearance. There are several blue and black damselflies in this group, with the widespread and abundant Azure Damselfly  most closely resembling the Variable. In some parts of the UK there are also rarer species that are similar to Variable Damselfly, for example Southern, Northern, Irish and Dainty Damselfly. There is also another blue and black damselfly which is easily confused with the Variable and that is the Common Blue Damselfly. Unfortunately, both the Azure and Common Blue Damselfly can be found in the same habitat as the Variable, making reliable identification a must. Additionally, individuals of Variable and Azure Damselfly have been observed where features have overlapped (more about this can be found on our Why? Group Forum). For example, there have been individuals with the markings of the Variable Damselfly and the pronotum of an Azure. We are keen to get a better understanding of the physical features specific to the Variable Damselfly, and this is where your records can come in.

 

Left: Variable Damselfly. Right: Azure Damselfly (both © Alex Berryman)

Left: Variable Damselfly, right: Azure Damselfly (both © Alex Berryman)

 

To answer all these questions, we need your help

For the first time, we are running a Variable Damselfly Survey and we would like as many people as possible to take part. We are asking volunteers to go out to known or potential Variable Damselfly sites and, using the survey ID guide and survey form, record Variable Damselflies. We are asking volunteers to take a photo of the Variable Damselflies they record, firstly to allow us to verify the record and secondly, to be added to a database of Variable Damselfly images.

There is a theory that the scattered distribution of the Variable Damselfly is partly due to varying water quality levels between sites. In order to obtain more data to explore this theory, we are teaming up with the Freshwater Habitat Trust’s Clean Water for Wildlife project. This project provides free water quality testing kits which are simple and quick to use. We are asking all our Variable Damselfly Survey volunteers to request these kits from the Freshwater Habitats Trust and survey the water quality, where possible, at sites where they have recorded Variable Damselfly. You can input the water quality data with your Variable Damselfly record. All water quality data will be shared with the Freshwater Habitats Trust.

 

Clean Water for Wildlife test kits show different levels of nutrient pollution - the darker the colour, the more polluted the water.

Clean Water for Wildlife test kits show different levels of nutrient pollution – the darker the colour, the more polluted the water. © Freshwater Habitats Trust

 

Within the next few weeks you will find all you need to take part in this survey on this page.

Click here to find out more about the Variable Damselfly.