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 113 records from 13 species have been submitted by 7 recorders from 20 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 19th July
  • Brown Hawker 19th 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.

Tuesday, 30 June 2020

Hull Dragons 2020: June summary

June has been a much more variable month than the dry and sunny May, with some rain, storms, more windy and more cloud. There were some good days for dragonfly watching, including a heat wave on the 3rd week, when temperatures reached 29°C in Hull. A total of 106 records of 11 species have been submitted during the month by 9 contributors. Foredyke Green Pond and East Park, with 7 species each, were the best sites in number of species. The only species recorded in May with no June records is the Large Red Damselfly. The Red-eyed Damselfly, Black-tailed Skimmer and Southern Hawker were added to the year list. An unidentified darter was recorded on the 25th June. 

My June odonate highlights
  • Watching a female Hairy Dragonfly coming to the shore by my feet at Noddle Hill fishing lake and start ovipositing on a dead branch was my highlight of the month. She moved on pretty fast before I could set the camera on her. As far as I know, this is the first time the species has been recorded ovipositing in the Hull area. 
  • Spotting a Red-eyed Damselfly at Foredyke Green, a new location for the species. 
  • At Ennerdale South Pond there was a strong damselfly emergence on the 2nd June. House Sparrows were feeding on them, sometime as I disturbed them and they flew up. As I watched and followed a female Banded Demoiselle by the river Hull, a house sparrow chased her and captured her!
  • Watching an ovipositing Broad-bodied chaser at Foredyke Green Pond.
  • Watching an Emperor and Hairy Dragonfly males patrolling and hunting on a stretch of the Beverley and Barmston drain, occasionally clashing.
  • As I was examining an emperor exuviae, I was surprised to see it moving, and a lodger emerged: a Larinioides cornutus spider! I had never seen spiders using dragonfly exuviae as retreats.

June species and breeding evidence

Southern Hawker. First and only record so far on the 26th June.
An emperor dragonfly resting briefly on plants near Foredyke Green pond.
Emperor Dragonfly. 8 records. Exuviae found at Foredyke Green Pond and Ennerdale South Pond.
Hairy Dragonfly. 2 records, with ovipositing female at Noddle Hill Lake.

Banded Demoiselle. Interestingly, all 4 records from the 2nd June from River Hull, Ennerdale S Pond and Cottingham.

Azure Damselfly. 22 records. Teneral at Beverley and Barmston Drain and Setting Dike. Oviposition noted at Pearson Park and Beverley and Barmston Drain.
Common Blue Damselfly. 16 records. Tenerals at Ennerdale S Pond. Mating pairs at Foredyke Green Pond and Ennerdale Pond.
Red-eyed Damselfly. Four records from four sites, the first on the 1st of June. They include a new site for the species, Foredyke Green Pond.
Female Blue-tailed Damselfly with Arrenurus mites (17th June).
Male Blue-tailed Damselfly with mites. Both at Foredyke Green pond (14th June). These are parasitic mites that feed on the host blood and drop to water once the host comes to mate to water. 
Blue-tailed Damselflies mating.
Blue-tailed Damselfly.
Blue-tailed Damselfly. 27 records, the most commonly recorded species. Tenerals were found at Oak Road, Ennerdale S Pond and Setting Dyke, oviposition was recorded at Beverley and Barmston Drain and Noddle Hill Lake.
Broad-bodied Chaser. 5 records. Oviposition at Foredyke Green Pond, where the photo above was taken.
Four-spotted Chaser. 6 records from 5 sites, including individuals emerging in a private garden.
Black-tailed Skimmer. 5 records, the first of the year on the 2nd June. A female was seen ovipositing at Snuff Mill Lane.

Saturday, 27 June 2020

Pirate wolf spiders in retreat

This afternoon I walked to local pond in search of dragonflies. Only Azure damselflies were active, half a dozen males bobbing about searching for females on the pond edge, a pair mating. As I looked for exuviae on the plant leaves, I noticed two female Pirate wolf spiders, possibly Pirata piraticus, in silky retreats at the base of branched burr-reed leaves, both carrying their bright white egg sacs. Apparently, unlike other wolf spiders, they build silky tubes, sometimes partially submerged, from where they hunt passing insects.

Monday, 1 June 2020

Hull Dragons 2020: May summary

We are running a Hull and surrounding area dragonfly and damselfly survey (Hull Dragons for short) in 2020, for comparison to 2019. I will post a monthly summary of the progress. This year is starting quite strong. The first flying odonata weren't seen until the 2nd week of May. During May, 55 records have been submitted to iRecord, from 9 species this year (compared to 23 records of 6 species recorded during the same time period in May). The increased number of records and species might be due to the favourable weather during the spring: we've had the sunniest spring and warmest May on record. This has not only provided ideal conditions for dragonfly watching, but might have also speeded up emergence. For example, the Emperor dragonfly records this year are almost three weeks earlier than in 2019.
My first Odonata record was on the 13th May, when while working on my desk by my front bay window a dragonfly, most likely a broad-bodied chaser, flew past. A tandem pair of blue damselflies was observed at St Andrews Quay pond on the 21st. Broad-bodied chaser are having a good year, with 4 records from 3 locations. The most common records were from Azure and Blue-tailed Damselflies. A very exciting record is that of a Large Red Damselfly at an ornamental pond in Willerby on the 25th May, given that we had no records for this species last year.
Finally, a Hairy Dragonfly was a very nice addition to the May list, on the Beverley and Barmston drain on the 31st.

First dates (as in adult identified species in iRecord submitted by 1st June 2020):
  1. Blue-tailed Damselfly, 20th May
  2. Azure Damselfly, 20th May
  3. Banded Demoiselle, 23rd May
  4. Broad-bodied Chaser, 25th May
  5. Large Red Damselfly, 25th May
  6. Four-spotted Chaser, 21st May, Paull Holme Strays 
  7. Common Blue Damselfly, 29th May
  8. Emperor Dragonfly, 29th May
  9. Hairy Dragonfly, 31s May