Wednesday, 12 August 2020

Common garden damselflies and dragonflies in the Hull area

Although a total of 23 species of dragonflies and damselflies have been recorded in Hull, only a subset of them can be considered regular in gardens, and a few species will even turn up in gardens without a pond. Here, I will present seven of the species most common in gardens, with identification tips. These species provide a useful benchmark to help you to identify rarer dragonflies and damselflies when in other habitats.

Two species of damselfly are common in gardens, where they regularly breed. They are even tolerant of fish, provided there are areas of thicker vegetation where their larvae can seek refuge, and will be even present in ornamental ponds with hard edges. Both are blue and black. 
1. Azure Damselfly
The Azure Damselfly gives an all vivid blue impression, it has a distinctive black hook or spur pointing forward on the side of its thorax, which distinguishes it in our area from the Common Blue Damselfly. I should have said males are all blue, as females are often green and black, as in the photo above. They can be found even in tiny garden ponds, provided they have plenty of vegetation near or in the pond. It flies from early May to early August.
2. Blue-tailed Damselfly
The Blue-tailed damselfly is the most common species recorded in Hull. It tolerates of all sorts of conditions: brackish ponds, polluted ponds, fish, and even poor weather! It  It has been described as a 'flying magic wand', as its black abdomen contrasts with the blue band near the tip. It has a distinctive two-colour wing spot, which is useful to identify females, which come in 5 different colour forms. It has a long flying season, from late April to late September.

3. Broad-bodied Chaser
This is a stunning dragonfly, the immatures are yellow and brown, with dark wing bases and a characteristic wide abdomen. In flight it is very reminiscent of a hornet. Mature males develop a powdery blue colour in their abdomen. This is a species likely to use newly built ponds, or ponds with plenty of bare or muddy margins. They fly early in the season, from mid May to mid August.

4. Migrant Hawker
This is the most common hawker in Hull, and is regularly found in gardens away from water. The individual pictured is a mature male, but it is immatures that are commonly found in gardens, and these have subdued colours and milky eyes. They tend to fly in the open at 3-5 m high, often going round and round in a relatively small area. It tolerates other individuals, which will congregate in gardens with plenty of food. It flies from late July to late October or early November. Although plentiful in gardens during their immature stage, they tend to breed in lakes and ditches. 
The usual view of a flying migrant hawker over a garden.

5. Southern hawker
A large colourful hawker, one of the most strikingly marked. The combination of apple green and blue markings in mature individuals is characteristic, as their habit of being curious towards humans, flying close as if checking you out. It tends to hawk close to the ground alongside paths and close to tree canopies, often in shaded, sheltered places. Females will lay eggs on floating wood or marginal vegetation in relatively shaded ponds. It has a long flight season, from mid-June until October.

6. Common Darter
A small dragonfly that hunts from the ground, or a perch, to which it returns. Immature individuals are yellow, but males become orangey-red, with two yellow panels on the side of the thorax. All individuals have a thin yellow stripe alongside their legs. One of the most common dragonflies. It can breed in garden ponds of medium or large size and including ornamental ponds. It has a long flight season, from June until November.

7. Ruddy Darter
The Ruddy Darter is less common than the Common Darter. It prefers to hunt from a perch, or from the ground, to which it returns after catching prey. Males have a more intense red than the common darter and a more waisted abdomen. Immature individuals and females are orange/yellow. The legs in both sexes are black. Flies from mid June to mid October. It breeds in ponds with plenty of marginal vegetation, although it can roam, and can be found in gardens away from ponds.

More information
  • If you are interested in identifying dragonflies and damselflies, Yorkshire Dragonfly Group has plenty of information on all the species and interesting sites to visit and runs an active Facebook group.
  • If you have any dragonfly records from your garden in the Hull area you can either submit the record to iRecord, or message me in the blog comments or on Twitter.
  • For more information on Hull Dragonflies and damselflies you can read the City of Dragons 2019 report here.

Saturday, 1 August 2020

Hull Dragons 2020: July summary

The first three weeks of July had very changeable weather, with plenty of overcast, muggy weather and some showers. Sunny spells were few, short and far between until the last week, where we enjoyed a few days of warmer, consistent sunny weather. 

Odonata highlights
Records were initially slow coming in July, but overall the month had a total of 144 records from 15 species have been submitted by 10 recorders from 23 km2, a few more than in June. As expected, the Blue-tailed Damselfly tops the list in terms of numbers of records, followed by the Emperor Dragonfly, and the Common Darter, with the same number of records. The surprise is that the Brown Hawker is tied 4th with the Azure Damselfly, with 11 records, more than were recorded during the whole of last year. The year total so far stands at 18 species.

First records of the year
  • Ruddy Darter, 11th July
  • Common Darter 11th July
  • Emerald Damselfly 19th July
  • Brown Hawker 12th July.
  • Migrant Hawker, 24th July
  • Small Red Eyed Damselfly, 25th July
Emperor behaviour
Emperors seem to be having a good year at the recording area. I've had a great time watching the behavioural differences between males and females. Males are a very showy dragonfly, 'presiding' over their territory, a pond, lake or a stretch of ditch, flying powerfully, over the open water, occasionally hovering on a spot, rising to catch an insect or flying over the banks, even checking birds flying past (I watched a brief Swallow-Emperor face off, both flying away!). They are always pulled back to the water, unlike other hawkers. At some point, they stop their hunting and patrolling to bask or finish a meal, usually on marginal vegetation facing the sun, but also rarely on the ground.
An emperor resting on the ground is an unusual sight. It is likely that it was sheltering from the wind.
Female's behaviour is completely different. They approach the water stealthily, flying low and near the shore, searching for oviposition locations (sticks or floating vegetation). They can be as colourful as males, as the following photo shows. If a male discovers a female, she will try and fly higher than him, curling her abdomen down in a signal of rejection. I've never witnessed a copulation in this species.
Ovipositing Emperor at Foredyke Green Pond. 
Male Emperor at Pickering Park. 
Pickering Park lake is large enough for several Emperors, but the northern side of the pond seems to be the most attractive and it is a place that year after year allows me to see males chasing and clashing for territory. In this case, one of the males landed in the vegetation to rest, while the other one carried on the patrolling. Ovipositing was also observed in the same area of the park. Ovipositing in July was also observed at Noddle Hill Lake, and Foredyke Green Pond.

Watching Brown Hawkers
Brown Hawkers are also having a good year. Four were seen hunting along rides and paths at Noddle Hill nature reserve. At the Beverley and Barmston drain near Beresford Avenue, I watched one for 20 minutes as it hunted repeatedly flying up and down the drain. It took advantage of the light breeze to glide back, then flew powerfully upwind, checking every passing insect, releasing some that were not of his taste. I was slightly amused as the hawker checked every passing creeping thistle seed (just like me!), and there were plenty floating in the breeze. I was hoping the Brown Hawker will have a rest at some point, but it didn't. Its territory-  and it was a male - was 20-30 meters along drain, with plenty of emergent and floating vegetation and a hedgerow on one side by the allotments. It flew high over the water, maybe over 1 m high, and then occasionally charged against the marginal vegetation, possibly to dislodge resting insects. Although I've got no photo opportunities so far, I enjoyed watching the species behaviour from a great vantage point.

Species gallery
Four-spotted chaser at Foredyke Green Pond.
Teneral Southern Hawker at Setting Dyke.
An Azure Damselfly rejects another's advance.
Blue-tailed Damselfly.
Teneral Common Darter at Pickering Park.
Common Darter at Midmeredale Pond.
Mating Blue-tailed damselflies at Pickering Park (note that the female is the same colour as the male, they are known as androchrome females).
Emerald, one of two males at Noddle Hill NR.
Small Red-eyed Damselfly at Paull Holme Strays. A mating pair was observed at Pickering Park.
A record shot of my first Migrant Hawker this year.