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

Friday, 4 October 2019

Hull Dragons: September summary

I didn't think I would write a September summary for Hull Dragons. However, the first three weeks of September were generally dry, sunny and warm - though breezy at times - allowing for plentiful dragonfly surveys. In contrast, the end of the month was very overcast, wet and the temperatures plummeted. Overall, 134 records were submitted to iRecord from 9 species in September by 4 observers. Although fewer species have been active in September compared to August (9 compared to 13), and the general diversity is lower, the spread of the records is increased, with the records coming from 30 km2. 83% of the records were for Common Darter and Migrant Hawker. There were 8 Southern Hawker records and 5 Ruddy Darter records, the remaining species having one or two records each in the month. Most notably, however, a male Willow Emerald was first recorded at East Park. This is not only a great addition to the Hull Dragons survey, but it is the first record for all of East Yorkshire (see my previous post about it here).

With the addition of these records and the dragonfly records submitted through Birdtrack, HullDragons has now accumulated over 500 records, which are far more than I would have anticipated at the start of the survey.

Other than my Willow Emerald twitch, my favourite dragonfly trip this month was at Noddle Hill. The sheltered 'Snake Pass' ride is a favourite haunt of Migrant and Southern Hawker, hunting and sunbathing and both Common and Ruddy darters also favour it. The NW corner of the lake, with a wide belt of marginal vegetation, in a sunny, sheltered corner, had plenty of Migrant Hawker activity, with several mating pairs, two of them sitting close to each other. A male Ruddy Darter was also on territory. The following are some photos of that survey on the 18th of September.
Female Migrant Hawker.
Male Southern Hawker.
Mating Migrant Hawkers.
Mating Common Darter.
The patrolling Migrant Hawker males over the water offered some opportunities for in flight photography.
Male Ruddy Darter on territory.

 List of species recorded on September

  1. Southern Hawker
  2. Brown Hawker
  3. Migrant Hawker
  4. Ruddy darter
  5. Common Darter
  6. Small Red-eyed damselfly
  8. Black-tailed skimmer
  9. Common blue damselfly
Note: this will be the last survey for HullDragons

Tuesday, 10 September 2019

Willow Emerald twitch at East Park

When I posted the Hull Dragons August summary on the 6th of September, I noted that, regarding the Willow Emerald Damselfly "there is a possibility this rapidly expanding species may make it into Hull in the near future". But I was never expecting the near future to be as quick as 48 hours! @pondwatcher on Twitter:

How exciting was that!?
The Willow Emerald benefits from urbanisation, as it favours permanent garden and park ponds, surrounded by trees or bushes. Its is a late flying species, making the end of the dragonfly/damselfly season more exciting. It is the only Odonata species that oviposits into live wood, usually thin branches overhanging water, where eggs induce a diagnostic, gall-like reaction in the wood in a pattern of parallel lines.
 After a few sporadic records, the Willow Emerald became a regular breeding species in the UK in 2009, where many breeding colonies were discovered in Suffolk. Since then, it has steadily increased in range west and north, and this year it crossed the Humber for the first time.
 Today, there was a forecast of sunny spells and light WNW wind, and I decided to got on a damselfly twitch. I arrived at the park at 9:00 and walked to the eastern side of the lake, where the area around the boardwalk is favoured by dragonflies and damselflies. The first sunny spell took about an hour to arrive. When it did, Migrant Hawker males became active, with up to 5 males sharing the area, patrolling and resting over the large patch of marginal vegetation (above), a single female making a short appearance.
A female Common Darter (above) sat on the railings of the boardwalk, the first record of this species in the park this year. After walking up and down for a while searching for the Willow Emerald and with another large cloud looming, I moved onto the western side of the park to search for Small Red-eyed Damselflies. No luck, not a single damselfly on the west side of the main lake or boating lake.
 After a hot drink in the cafe I returned to the boardwalk. More searching of trees and marginal vegetation and walking up and down the boardwalk. The Migrant Hawkers were active so I watched them for a while. It was 12:20, the temperature quite pleasant in the sun, barely a breeze. Two male Common Darters were in attendance, chasing. After three hours in the park, I thought I had to content myself with a tandem pair of Common Darters, which were looking for an oviposition site. Maybe the Willow Emerald had succumbed to predation, of moved on. Another cloud was coming. I thought I'd stay for the next sunny spell. Then, a lovely, large sturdy green damselfly flitted about, checked the passing pair of hesitant darters in tandem, and sat on a leaf near the boardwalk: yes! the male Willow Emerald! It gave the impression of a sizeable insect, it is indeed as long or a bit longer than a common darter, and a stronger flyer than the common emerald. It sat on exposed leaves over the water, moving every now and then to another perch. It sat on alder leaves, on branched burr reed flower heads and leaves. I could take plenty of photos, as I watched it for about 20 min. A lovely damselfly tick!
This photo shows the 'spur' on the side of the thorax and the pale pterostigma with dark edges.
The pale appendages are also distinctive. No bluish pruinescence is apparent.

Willow Emerald males often sit on low branches of trees, overhanging water, which are the ovipositing sites chosen by females.