Invertebrate report for first half of 2013

On 13 February - only a week or so from snow in the garden which wasn't to be the last – there was sunshine as well as a bit of warmth in the sun. On a stem of rhododendron just inside the entrance to the City of London Cemetery was my first ladybird of the year – a Pine Ladybird Exochomus 4 pustulatus, and there were more enjoying the sunshine, plus torpid ones sheltering in the dried up flower-husks, where they probably overwinter. Crocuses and Winter Aconiteswere flowering, and just one flower of Lesser Celandine, and on the white flowers of Viburnum, three species of hoverfly were found. Most of these were Drone Fly Eristalis tenax, and there were lesser numbers of the Marmalade Hoverfly, Episyrphus balteatus. The third species was a single individual and probably Melicaeva auricollis. On an adjacent Mahonia, its yellow flowers were attracting mainly Honey Bees, Apis mellifera.

No butterflies were seen, whereas last year Red Admirals were seen on Wanstead Flats on 26th February; it has been reported that butterfly numbers were considerably down last year, and this will doubtless be reflected on numbers this year. On the heathers – many of which were flowering – quite a lot of insect activity was taking place, with the flowers large numbers of Honey Bees as well as the large and familiar Buff-tailed Bumble Bee, Bombus terrestris.

Disappointingly, by the next day the weather had again turned colder, and this trend was to continue well into April and even May, with a few days of relative warmth followed by mostly unseasonal cold. I'd intended to put out a moth trap early this year, but on the few occasions that I did the catch was nil until 10th April, when there 3 Common Quakers nestling in the egg-boxes the following morning. In the whole of April I had 6 species and 28 specimens of moth in the trap. However, the trap occasionally does contain other things, and one such on 11th April was a wasp of an Ophion species.

Pond Skaters were to be seen on my small garden pond from about this time, too, and Eristalis tenax hoverflies were quite frequently seen on the slightly warmer days. The 13th April was one such, and in the City of London Cemetery – around the heather beds – together with the bumblebees and a few spiders, was my first Bee-fly Bombylius major of the year. Bee-flies will not fly in temperatures less than 17ºC., and considering the extended winter and long drawn-out spring, I saw more and in more places than I've ever seen before. The last – though not in the Wanstead area – was on 6th June. There was a Comma butterfly in the garden on 15th April, and mining bees (Andrena species) were appearing on Wanstead Flats by the 29th as well as the common Buff-tailed bumblebee Bombus terrestris.and Red-tailed Bumblebee Bombus lapidarius. A Small Tortoiseshell butterfly was also spotted on Wanstead Flats.

By the 1st May, Tim Harris – who had been putting out a moth trap in Belgrave Road at the other end of Wanstead Flats to myself - had accumulated a total of only 16 moth species during this year, and I only 6. However one or two new species for the area were cropping up in early May, including the micro-moth Pyrausta despicata and a Red-green Carpet.

On the butterfly front, Holly Blue butterflies began to appear in my garden and elsewhere on 2nd May and on 3rd there were Orange Tips, Speckled Wood and Peacock in Wanstead Park, plus Green-veined Whites, Large Whites and Small Whites in Aldersbrook Exchange Lands.

My first damselfly of the year was – as usual – a Large Red, in my garden on the 6th May, after which I had a look at Wanstead Park. An invertebrates of particular interest was a Slender Ground-hopper Tetrix subulata at the east end of Heronry Pond. I have only ever seen one before, and that too was by Heronry Pond, although in 2009. Also in the pond was the larva of a Tipula species Cranefly. I'd been catching sight of a Great Diving Beetle in my garden pond for some time, but it had surfaced only briefly then dived and swam rapidly out of sight into the depths. On 7th May I managed to photograph it at the surface and identify it as a female Dytiscus marginalis.

On 7th May Tim had a Broom Tip Chesias rufata, which was a new species for the area. This was worthy of a bit of research, and Tim could find no reference to any records in our area since at least 1989 on the Essex Field Club database. Indeed, in Essex it only seems to have been recorded in a handful of squares since that time. Wanstead Flats does have plenty of broom, so we may have a population. Another new species in the Belgrave Road trap was a Yellow-barred Brindle moth on 20th May.

By the latter part of May a variety of hoverflies were now visiting my garden including Helophilus pendulus and particularly Eristalis tenax.

On 27th May Tim Harris discovered a Green Hairstreak colony on Wanstead Flats - the first report of these butterflies in our area save for a possible one I saw some years ago by the Grotto. It is a widespread species, but found in very localised communities due to habitat loss so it is quite something that we have a population here. Small Copper butterflies were also beginning to emerge.

More species of damselflies were beginning to emerge as the weather became warmer at the very end of May. Most that were seen on 31st May were in the teneral stage, which is just after they have emerged from the pupal stage and either or both Azure and Common Blue. There were also Large Red, some Blue-tailed and some Red-eyed damselflies. By the Heronry Pond, leaves of Flag Iris had numbers of the Long-jawed Orb-weaver Spiders Tetragnatha extensa on them, and an adult and a few very small Slender Ground-hoppers were seen in the same location as the adult seen on 6th May. This would seem to indicate that we have a healthy population.

Also on 31st May, the Soldier Beetle Cantharis rustica was seen in the Exchange Lands and Flea Beetles - Altica species - were appearing on the leaves of water-side plants in Wanstead Park. Large White butterflies were seen, and there were many Craneflies around in the grassland.

(See also Early Invertebrates 2012 for comparison with last year)

Paul Ferris

Update on Slender Groundhoppers in Wanstead Park

In 2009 I came across my first ever sighting of a Slender GroundhopperTetrix subulata, in Wanstead Park. As this species was not previously known to the area - or indeed to Epping Forest - I wrote an article about it here.

Tetrix subulata Wanstead ParkTetrix subulata in Wanstead ParkOn 6th May 2013 I was walking close to the water-side by the east end of Heronry Pond when I disturbed a "grasshopper" which jumped into the pond. So early in the season, I assumed it was actually a groundhopper as these tend to be around much earlier than other orthoptera.

Through my binoculars I could see that it was in fact a groundhopper and that it seemed to be floating comfortably in the water. As I watched - not being able to reach it for a 'rescue' - it jumped out of the water onto the land. This species - the Slender GroundhopperTetrix subulata - favours damper places, and it certainly seemed to have no problem being in the water or getting out of it! On 31st May, in the same spot, as well as an adult I saw that there were two or three smaller individuals. We do seem to have a colony of this interesting and unusual - or at least rarely reported - species for Epping Forest right here in Wanstead Park.

 

Paul Ferris, 7th June 2013

 

Green Hairstreak butterflies in Wanstead

The nearest record of a Green Hairstreak to the Wanstead area shown on the Essex Field Club's website is dated 2011 and is from the south part of Forest Gate. The Green Hairstreak is a butterfly which may be found in a variety of habitats including heaths, downland and scrubby wasteland. It is a widespread species, although becoming localised. It was previously more common, but much of its territories have been lost due to a variety of changes to its habitat by man-made activities.

Green HairstreakGreen HairstreakI have only seen one possible individual locally, near to the Grotto and quite some years ago, and so was excited when on 27th May I received a text from Tim Harris which read "Green Hairstreak colony on Wanstead Flats". I of course enquired of the whereabouts, and was instructed to look for a bramble patch on the Flats, where he had seen six or possibly more.

The bramble patch which I thought may be the one showed no sign of butterflies. Indeed, by the time I arrived the wind had increased and clouds were beginning to build up - neither good for butterfly flight. I walked further on and in a patch of scrub with brambles, hawthorn and a persistent Chiffchaff singing, saw about five Green Hairstreaks making forays each time the sun came out, as well as two Holly Blues playing. Green Hairstreaks never open their wings on landing, so once they have alighted their green colour against the green of the foliage can be something of a camouflage. Too, I was some way off their actual position beyond a bramble patch - and they were quite high up, perched mainly on hawthorn. For a frustrating hour or so I tried to get a decent photograph, but conditions did not aid things. However, eventually I managed a photograph that I was satisfied with.

Tim has just contacted me as I write this, saying how nature can surprise us. We could travel miles to see something less than usual, and yet have some wonderful - and sometimes even quite scarce - creatures on our doorstep!

Paul Ferris, 28th May 2013

Wanstead Flats Skylark survey, 2013

Wanstead Flats probably has one of the largest breeding Skylark population in the London area, possibly within the M25 motorway. Their song during the spring and summer months is a familiar accompaniment to those visitors to the Flats who give themselves time to listen; local dog walkers may well be aware of them, though the weekend football players less so!

SkylarkIn fact so familiar have the Skylarks been to me since I moved adjacent to Wanstead Flats in the 1960's that I perhaps hadn't borne in mind until more recent years just what a wonder it is for them to live here. Considering the amount of noise, light, dogs, people and other disturbances that the Flats are prone to, the Skylarks persist.

For the last few years local naturalist Tim Harris - together with a number of other naturalists and birders - has been trying to ascertain just how many Skylark territories there may be on the Flats. A few years ago we encouraged the City of London Corporation in their role as Conservators of Epping Forest to erect notice-boards advising people of the presence of Skylarks and particularly asking dog-owners to try not to let their dogs roam free over the areas that may provide nesting-sites for the birds.

skylark notice wf 130320 50362The first displaying male was singing on 2nd February this year. In early March, Tim, with the help of a few others, erected about 20 supplementary temporary notices. Dog-walkers were soon seen to be reading these, and hopefully some will take heed and try to keep their dogs away. As has been said, considering that the area is so disturbed, the larks do remarkably well, but the last two seasons have seen an apparent decline in breeding numbers so everything that we can do to try to stop this is important.

To ascertain this year's population, Tim has proposed surveys take place at least – if possible – each week. Not everyone can make such commitment, so provisions were made to hand out maps and survey sheets at a preliminary survey on 16th March so that people might be able to pop over for an hour or so when they have some time. That way we could start to build up an accurate picture of how many pairs there are. Later in the season we could look for family parties and try to estimate the breeding successes of our birds.

Skylark on Wanstead FlatsA male Skylark on Wanstead Flats. Skylarks sometimes sing from the ground.So, on Saturday 16 March, a group of six people assembled at the car park on Centre Road. The day was hardly an ideal one for such a survey. Thoughts of a spring walk across the Flats listening to the gentle sound of the lark became a reality of cold strong winds with a deal of rain. However, the larks were singing, and we managed to positively identify three displaying males, and eight or possibly nine birds in all. In addition, at least six Meadow Pipits were seen at one time and even some of these small birds were attempting display flights in the strong winds. Meadow Pipits are another important element of Wanstead Flats, their melancholy little song less obvious to many people than that of the Skylark but evocative of moors, mountains and wide open spaces.

Our introduction to the surveying process completed, and timely-so for the rain was beating down even harder, we all repaired to the more convivial surroundings, on such a day, of the Gatehouse Pantry in the City of London Cemetery, where tea, coffee, hot chocolate and a variety of warming foodstuffs were enjoyed by all.

 

A video about the Skylarks of Wanstead Flats is available here.

Tim Harris has an article available on the Wren Group's website here.

 

Paul Ferris

Wanstead Waterbird Survey

The Wren Wildlife and Conservation Group's monthly winter waterbird survey took place on Sunday 13th January. This survey, the Wetland Bird Survey (WeBS), is the scheme which monitors non-breeding waterbirds in the UK. The principal aims are to identify population sizes, determine trends in numbers and distribution and to identify important sites for waterbirds. (from RSPB's website at http://www.bto.org/volunteer-surveys/webs)

Tim Harris – who usually co-ordinates this and leads the walk around Wanstead Park's waters – was away and he's asked if I would lead it in conjunction with Jackie Morrison. So it was that on a somewhat cold day, but at least not with the threatened snow, I met with Jackie by the kiosk in Wanstead Park and together with Gill James, Linda and David we proceeded to count the birds.

Gulls and Coots on Heronry PondGull and Coot competition on Heronry Pond...We began with the lake onto which the kiosk faces – the Heronry Pond. Here, as usual, were a largish number of Coot, some Canada Geese and plentiful gulls, almost all of which were Black-headed. There were a dozen Mallard, a few Tufted Duck and Pochard, a scattering of Gadwall and a Cormorant – which was perched across the lake on the branch of a tree. Five still-brown-streaked young Mute Swans flew off, and caused a degree of uncertainty during the course of the counting as they tended to move around a bit. This isn't at all unusual, particularly as the parent birds are becoming territorial at this time of year and are chasing their young – and any new arrivals – off “their” lake. Numbers of the species mentioned, plus Moorhens, mounted as we moved down the north side of the lake towards the Shoulder of Mutton pond.

At the Shoulder of Mutton the predominant species were Gadwall, with 29 counted, plus about the same number of Black-headed Gulls. A new species for the day was a Grey Heron.

Retracing our route past Heronry Pond, we reached Perch pond where – apart from Black-headed Gulls – Gadwall were the the most plentiful species.

Mute Swans...and somewhat territorial Mute SwansFor some reason that I've never fully understood our largest body of water - the Ornamental Waters - is not included in the survey; the numbers of waterbirds that may be found there is not required. As such, and as I was cold, had other things to do and had suffered the mud-slips that would be encountered a couple of weeks ago, I elected not to walk around the lake and count the birds. Linda also chose that lesser (and less muddy!) option. We returned to the kiosk for a warming cuppa before returning to our homes.

However, the others did do a count – although not finding any different species. Whilst we were surveying the waters of Wanstead Park, Debbie was counting the birds on the Eagle Pond and Richard Oakman the Basin. Richard had the pleasure of seeing three of a less common species in our area, Wigeon, plus the only grebe – a Great Crested Grebe – seen that day. Before I met the others in the Park, I'd counted the birds on Alexandra Lake, Wanstead Flats. Here, the only species not seen elsewhere was Greylag Goose, with a count of 30. The overall results are presented in the table below.

These waterbird surveys provide valuable data about the country's wildlife, and can be a pleasant social occasion with the opportunity to learn more about our wildlife. If you would like to attend, you'd be welcome – whatever your level of expertise or knowledge. Look at the Wren Group's website at http://www.wrengroup.org.uk/ for more information.

 

Wanstead area Water-bird Count 13/01/2013

 

Species

Alex

Basin

Eagle

Shoulder

Heronry

Perch

Ornamental

Total

Little Grebe

 

 

 

 

 

 

 

nil

Great Crested Grebe

 

1

 

 

 

 

 

1

Cormorant

 

 

1

 

1

3

1

6

Grey Heron

 

 

 

1

 

1

 

2

Mute Swan

7

2

6

2

10

5

2

34

Greylag Goose

30

 

 

 

 

 

 

30

Canada Goose

112

2

26

 

15

4

8

167

Wigeon

 

3

 

 

 

 

 

3

Gadwall

12

101

2

29

16

18

19

197

Teal

 

 

 

 

 

 

 

nil

Mallard

37

3

14

3

27

1

31

116

Shoveler

7

2

3

 

1

 

 

13

Pochard

 

 

4

 

3

 

9

16

Tufted Duck

6

7

47

1

30

3

16

110

Water Rail

 

 

 

 

 

 

 

nil

Moorhen

18

7

7

 

4

1

5

42

Coot

88

24

56

5

35

10

18

236

Black-headed Gull

30

 

210

26

162

44

57

529

Common Gull

 

 

6

1

4

 

 

11

Lesser Black-back

 

 

 

 

2

 

 

2

Herring  Gull

 

 

1

 

 

 

 

1

Paul Ferris, January 2013