Delving into Dragonflies

On a bright summer morning, Farm Environment Adviser Emily Stacey set off on a dragonfly walk through the Panshanger Nature Reserve, a former sand and gravel quarry just outside of Hertford, guided by the Herts & Middlesex Wildlife Trust. The reserve consists of a mosaic of different habitats including parkland, woodland, wildflower meadows, wetlands and reedbeds.

From the late 1700’s to early 1900's, the Panshanger Estate had been owned by the Cowper family. However, in the 1980’s the site was bought by Tarmac for gravel and sand abstraction. This led to the creation of the lakes that are present today. Part of the site has been open to the public since 2014 and more will be restored and opened as the abstraction works come to an end.

The wetland and grassland habitat created has been especially beneficial for one group of insects, the dragonfly. The site has been named a dragonfly hotspot by the British Dragonfly Society and is home to 19 species of damselfly and dragonfly.

The morning took attendees on a walk along the dragonfly trail, winding through reedbeds, woodland, along the lake edge and across the River Mimram, which is an extremely important habitat as a rare chalk stream. The light wind did not deter the dragonflies and damselflies from making an appearance as they basked on sunny logs and darted along the vegetated lake banks.

How to distinguish between a dragonfly and a damselfly?

With the exception of one species, the damselfly is smaller and more delicate than the dragonfly. If you have a good eye, and are lucky enough to see them land, look at how they hold their wings. Damselflies perch with their wings closed, whilst dragonfly wings remain open. 

Dragonflies:

Dragonflies exist for most of their life as larvae, living in the water for 2-3 years before transitioning into adults. They miss the pupal stage unlike other insects and live as adults for around 2 months, remaining near to the water. Although, the females will stay away from water until they are ready to mate.

Three types of dragonflies were spotted during the morning walk: Hawkers, Darters and Chasers.

Hawker dragonflies are the largest of the three. They do not perch and instead continuously fly around. The Southern Migrant Hawker (also known as the Common Hawker) was seen in large numbers on the site. Despite being known as the Southern Migrant Hawker, it made itself a resident in the 1940s. It is also the smallest of the hawker dragonflies, and the males are blue and the females are brown. These are not to be confused with the Southern Hawker, which is larger. They are also slightly different colours, as the males are green and the females are brown and yellow. Another species seen on the day was the Brown Hawker, which is a large brown dragonfly with gold wings. The males have small blue and yellow markings, and the female have yellow markings.

Male southern migrant hawker (British Dragonfly Society) to the left and a Female southern migrant hawker (Emily Stacey) to the right.

The Common Darter was the main darter species seen on the day. They like to perch and are often seen basking on tree logs in the sun. It is one of the two red darters seen. The Common Darter is brick red, whilst the other is the Ruddy Darter, which is a ruddy, blood red.

Chaser dragonflies are shorter and fatter than the other species and have heads that are squarer in shape. These tend to perch and wait to chase or ‘dart’ after prey. Unlike other dragonflies that lay eggs in stems, chaser dragonflies lay their eggs straight into the water. At Panshanger Park they were seen swooping down to meet the water’s surface to lay their eggs. The most common is the Four Spotted Chaser, which likes sunny areas of tall, sheltered vegetation. They are brown with two distinctive black dots on each wing.

There is also the skimmer dragonfly, which is a similar shape to the chaser, however, the key difference is that the chaser has dark coloured triangles on the hind wings.

Damselflies

The Common Blue Damselfly is a regular sight at Panshanger Park, perching in the warm sheltered grassland next to the lakes. The males are bright blue , whilst the females are darker.

Another species of note was the Willow Emerald Damselfly. This is a larger damselfly which is dark metallic green with pale spots on the top of its wings. This species goes against the rule in that it rests with its wings slightly open. Most damselflies lay their eggs in the stems of plants on the shoreline. The Willow Emerald species only lays its eggs in the stems of willow trees. If you study a willow branch next to a waterbody you may see scars/bumps on the stem from where a female has laid 6 eggs, 3 either side of the branch.

It was a lovely morning spent exploring the park and learning about the wildlife that make it their home. Although peak flight activity is in June and July, you can see dragonflies at Panshanger Park from late April into September. Go see them for yourself!

The Wildlife Trusts run a range of training courses and walks across their areas. Visit the website to see what is going on near you: https://www.wildlifetrusts.org/events

Visit the British Dragonfly Society website for further details of the different species of damselflies and dragonflies: https://british-dragonflies.org.uk/odonata/species-and-identification/