Sightings


A possible flower association of Ferdinandea cuprea

This note was written for the national Hoverfly Newsletter and has been published in the autumn 2017 edition issued by the Dipterists’ Forum. It may interest some other naturalists too.

On 19 August 2017 I visited a large woodland site in the Cotswolds. The weather was cool and there had been rain during the night; the grass was still wet in the lower and more shaded rides. As there was very little insect activity I decided that I would spend some time photographing the Naked Ladies which were a conspicuous and colourful feature of the scenery. By Naked Ladies, of course, I mean the flowers of Colchicum autumnale, also known as Meadow Saffron.

My eye was soon caught by an unusually downward facing flower within which there seemed to be some activity going on. I found that there was a female Ferdinandea cuprea moving around inside the base of the inverted flower. The hoverfly may have been foraging for nectar or pollen but as the surroundings were devoid of flying insects, and because of the hesitant way it began to emerge from the flower on my approach, I formed the impression that it might have been sheltering under the tent of petals for some time.

The day warmed up later, but not very much, and the few flowering plants in the woodland continued to attract almost no hoverflies. I had walked some distance from my first sighting of F. cuprea when I spotted a particularly shapely group of Naked Ladies and decided to take their photograph. While I was getting into position I became aware that a fly of some kind was coming into view and was clearly moving towards the same flowers. I quickly took my shot, hoping that the fly might add some interest to the image. Fortunately, the fly came out almost as well-focused as the flowers, and is clearly again a female F. cuprea. On this occasion the hoverfly did not land on the flower; it apparently detected my presence, changed course and flew away.

 

 

 

 

 

 

 

 

 

 

 

 

These two separate sightings of F. cuprea with C. autumnale may be a random coincidence. However, as I am not aware of any reported association between this flower and any species of hoverfly, the observation may be of some interest. In Hoverflies of Surrey (Surrey Wildlife Trust, 1998) Roger Morris does not include C. autumnale either in the extensive list of flowers visited by hoverflies (Appendix 2) or among those mentioned in his account of F. cuprea.


Coombe Hill and Cobney Meadows on 21 October

Little sign of any rise in water levels in the Severn Vale: at the GWT reserve at Coombe Hill, the north scrape was till dry, there was just a small puddle in the south scrape, but still shallow water on the Long Pool (the only place where water has lasted throughout the summer). Some hay late had recently been cut on neighbouring fields – a sign of just how dry the conditions are. Storm Brian didn’t succeed in blowing the Grundon Hide away, but made it hard to see songbirds, which stayed in thick vegetation. 

The colour-ringed pair of Mute Swans that had nested locally were still present, with their eight full grown cygnets; at least 260 Greylag Geese grazing, eight Canada Geese, one very striking Canada x white Farmyard Goose hybrid, four Wigeon (the first of the winter here), 160 Teal, eight Shovelers, 11 Grey Herons, a single Green Sandpiper left; 6 Redwings flew over to the southwest (also the first  of the winter).

 At Cobney Meadows, not much water left on the flight pond either: 1 Sparrowhawk hunting, 1 Buzzard; a single Snipe on the old Parish Drain.

 


Black nightshade in maize stubble

Fodder maize in a Standish field was harvested during the week. Gulls and woodpigeons are feasting on the dropped cobs. I’ve taken the opportunity to check the weed flora hoping to find some unusual alien plants, but the ground is overwhelmingly dominated by Black Nightshade, Solanum nigrum, which is also common in my garden. It is a member of the potato family, and has small starry white flowers and round fruit that turn from green to black without going through a red stage (unlike Woody Nightshade, Solanum dulcamara, that has purple flowers and fruit that go from green to yellow to red.)


Another ringing session at Ashleworth Ham on 1 August

This was the ninth session out of twelve in the British Trust for Ornithology’s Constant Ringing effort at Ashleworth, three each month from May to August.  This study has been going on at Ashleworth for twenty years now.

Starting before sunrise, it didn’t look, at first sight, as though there were many birds about: little birdsong (just a few bursts of Willow Warbler: were these adult birds having a last session at the end of the summer, or newly hatched young ones, trying out their song for the first time?), nor much sign of bird activity early in the morning; yet the ringing session showed there were still quite a lot of birds about. 

Conditions were quite good to start with (overcast, no wind), but unfortunately the wind rose rather earlier than forecast soon after half past seven (the wind makes the nets belly out like galleon sails, so that the birds bounce off instead of getting caught).  So the catch, although just above the average for the time of year, was limited to 73 birds; 44 of them were summer visitor warblers all the same; interestingly, the vast majority of them were juveniles (probably locally bred as they were nearly all still in post juvenile moult), so it looked as though most of the adults had moved out already. Birds caught: 1 juvenile Grasshopper Warbler (another indication of local breeding, picture below by Mervyn Greening); 4 Sedge Warblers (all juveniles); 23 Whitethroats (not a single adult); five Blackcaps (one adult); 6 Chiffchaffs (just one adult in moult); 5 Willow Warblers (one adult in moult); plus the usual array of residents: as many as seven Reed Buntings (all juveniles); a single juvenile Great Tit; one juvenile Long-tailed Tit; no Blue Tits; 2 juvenile Treecreepers; one Blackbird; couple of Dunnocks, couple of Robins, five Wrens (all juveniles); three Linnets , three Goldfinches, two Bullfinches. 

Other birds on the reserve: 1 Sparrowhawk; 2 Buzzards; 1 Green Sandpiper; one Redstart; about 10 each of House Martins and Swallows hawking insects, probably migrants on their way south; one Raven; a flock of at least 50 Goldfinches (autumn coming!)  

No hay has been cut as yet on the reserve (which no doubt gave the Reed Buntings time to raise their second broods).  Water levels low on the scrapes, but a nice stand of Flowering Rush in the middle pool.  


Interesting observations at Coombe Hill, even in dry conditions

Recent rain in Gloucester hasn’t raised water levels at the GWT reserve at Coombe Hill; the north scrape is completely dry, and the south scrape is almost dry – just a dribble of water left yesterday 29 July.  There is still water on the Long Pool however, though the Long Pool hide is closed (as in previous years at this time), because of a hornet’s nest.

Interesting stuff however: at first sight, there were no birds on the north or south scrapes.  But occasional Little Ringed Plover calls could be heard from the Grundon Hide; after a while these became ever more anxious, as two Kestrels landed in the short aquatic vegetation in the north scrape; the Kestrels appeared to be an adult female accompanied by a juvenile, probably recently out of the nest, and were clearly hunting on the ground.  The adult LRP kept running around on the floor of the scrape, then undertaking nervous circular flights round  and round; the chicks (which ought to be fledged by now, as they were first seen on 3 July and someone recorded them during the week as fledged) never showed any sign of flying and stayed round the scrape – there was no sign of LRPs on the Long Pool.  Not sure what the outcome was: the Kestrels were never seen actually to catch any prey, while the chicks were never seen to emerge from the vegetation unscathed.

Surprising, on one hand that the chicks didn’t try to fly, but just lay doggo, on the ground; they can’t yet be confident of flying away; and on the other that Kestrels were trying to catch them on the ground: any other raptor, you might have thought, but surely the windhover is an aerial predator.

Otherwise, mostly on the Long Pool, which still attracts passing waterbirds:  eight unringed Canada Geese, 100 Mallard, 180 Lapwings, five Green Sandpipers, and two Snipe; still at least eight Sedge Warblers (generally churring rather than singing) in the thick ditch side vegetation through the reserve.

And lots of wild flowers now; Corky-fruited Water Dropwort and Flowering Rush among others


Ringing at Ashleworth

Yesterday 22 July we carried out another of the regular Constant Effort Site ringing sessions at Ashleworth, where no hay has as yet been cut on the GWT reserve.

Outwardly, it appeared that there were few birds about: scrapes almost dry, little or no birdsong, not much activity.  But the ringing showed that in fact there were large numbers of recently fledged young birds present, recently emerged from the nest, often just completing their post juvenile moult, before setting off on their long migration journeys to the Mediterranean and sub-Saharan Africa.  It is very likely that all these juveniles were locally bred, as they would hardly move off before completing this moult, and almost none of them showed any additional fat (which migrants arriving from outside the reserve would be likely to do).  So, this represents a snapshot of breeding attempts and successes.  After Friday’s fairly heavy rain, conditions were surprisingly favourable: windless in the early morning, with a light cloud covering which made the nets more difficult for the birds to see.  We had a catch of 93 birds, slightly above the average for the mid July visit, and made up as follows:

  • One juvenile Kingfisher; unusually, no Redstarts caught, though there had been several adults earlier in the season; one juvenile Grasshopper Warbler (particularly interesting, as on earlier visits we had caught an adult male and female in breeding condition: this is a very strong indication of local breeding); no Reed Warblers caught or heard, which suggests that they did not attempt to nest this year; nine Sedge Warblers (mainly juveniles, but a couple of ringed adults, caught earlier in the season; so they haven’t left yet, but will be going soon); as many as 32 Whitethroats (all but one were juveniles, showing that this species has increased greatly in the hay meadow hedges in recent years); seven Blackcaps (two adults and five juveniles, probably birds that had nested in slightly higher ground round the edges of the reserve, and were now moving into lower areas; like Whitethroat, more than usual); no Lesser Whitethroats this time, though we have caught juveniles on previous visits; eleven Chiffchaffs (every man jack of them a juvenile); two Willow Warblers (one adult and one juvenile); nine Reed Buntings (again, all juveniles; late hay cutting may have helped this species which nests in long vegetation in hayfields).  Also, as usual, a variety of resident breeders: one juvenile Dunnock; seven Wrens (nearly all juveniles); three juvenile Robins; one juvenile Great Tit; one juvenile Blue Tit; five Long-tailed Tits, mainly juveniles; one adult Linnet; one juvenile Goldfinch.

Few other birds of note around the reserve: one adult male Peregrine perched on a dead willow; about 20 House Martins and 20 Swallows hawking insects (probably locally bred juveniles as well).Mervyn Greening, Mike Smart

Mervyn Greening, Mike Smart


Strawberry theft by small animal

We have several raised beds with strawberry plants, and nearby another bed with courgette plants. They are all contained in a cage covered in chicken wire, to keep out the deer and pheasants, among other animals that would eat our vegetables. This is out in the country, near Caudle Green.

We noticed that we were not getting many strawberries and sometimes we found unripe ones cut off from their stems and lying on the ground under the plants. Today we found part of the answer. On going to pick some courgettes we found this huge stash of rotting strawberries. A creature has been picking the strawberries and carrying them to the courgette bed.

We have a huge population of voles in the garden, so perhaps it is them, or perhaps a mouse?

Richard and Jenny Beal


Curlews along the Avon

Baby Curlew 1 July 2017

I had a very interesting day looking at Curlews along the River Avon, both the Worcestershire  and Gloucestershire banks, on 1 July.  One site on the Gloucestershire bank is a Lammas meadow, cut late for hay (not silage) and above all, cut gradually, strip by strip; access by the public is not allowed in the breeding season from 1 March to 31 July, to avoid disturbance of ground-nesting birds.  Rather little of the hay had been cut (less than 10%), but the Curlews, both young and old, seemed happy feeding on the cut strips.  Looking along the cut strips from a distance with a telescope, I could see two young birds of the year: one was already able to fly (which is a very early date, last year I saw fledged birds from 9 to 23 July); it was obviously a young bird from the short, only partly de-curved beak, and from the bright spangled plumage on the upperparts – dark centres and buff edges, recalling juvenile Ruff.  The second youngster was nearly full grown, but with no proper tail and only a fluffy ball of down at its rear end, and the wings not yet fully developed, not showing beyond the tail, so not yet flying; presumably two different broods.  When I approached, the fledged bird flew off on its own; the other one disappeared, no doubt lying doggo and burying its way into the grass; one adult (apparently a male) hung around, very anxious, repeatedly giving the two note alarm call (“cour-LEE”, accent on the second syllable, repeated rapidly), which is no doubt the signal to big chicks to lie doggo.  Another adult got up a bit further on in the long grass, doing the five note alarm: I suspect this call means that there is another brood in there, with perhaps slightly younger chicks.  At this site last year, a little group of fledged birds of the year were present for a few days, in a group together, after the last adults had left; I took them to be locally bred birds, but they might of course have been passage birds from elsewhere; I’ll be interested to see if the same happens this year.

I then moved to the east bank, in Worcestershire.  In one hay meadow there, I have seen fledged young in the last couple of years.  On previous visits this year, I have found adults present on this field, but on my last visit, there was no sign of them, though I walked right through the field.  I walked right round the field again on 1 July, and had almost completed my circuit, without seeing any Curlews.  Then, suddenly, only ten yards away, a very agitated adult rose, calling desperately, and I heard quiet calls, apparently from young birds.  When I looked closely  I found two freshly hatched young, with large remains of eggshells still in the nest, (see pictures); they were so young, they didn’t even run away or burrow;  I think they must have hatched that very day. This shows, firstly, how closely birds will sit, without rising at the approach of an observer: it’s very easy to overlook birds acting so secretively.  Secondly, this is an incredibly late date for hatching: it must be a replacement clutch.  The young won’t be flying until about 5 August, even if they manage to escape hay-cutting: I’ve spoken to the farmer, who is sympathetic, but he needs to cut his hay some time!  After this, I then visited another nearby field, where the farmer purposely leaves his fields uncut until the Curlews have fledged.  He has already seen young in this field, and on my visit there was an anxious adult doing the five note alarm: I’m sure there is at least one young bird in the long grass.  At this site, there was a flock of up to 15 adult Curlews in mid-June: I take these to have been failed breeders or non-breeders, gathering in a flock before departing to moulting and wintering sites on the estuary and coastline.  No sign of them on 1 July, just the one anxious adult.


Holy Bee-flies!

Bombylius major (Dark-edged Bee-fly) in a Cotswold churchyard.

No, the title of this note is not an unexpectedly pious exclamation from the script of a new Batman film, but rather the consequence of an idea that has been developing in my mind as one of the county fly recorders.

Dark-edged Bee-fly feeding.

Our most common bee-fly is Bombylius major (Dark-edged Bee-fly) which appears quite early in the year (the first Gloucestershire records in 2017 are from 15 March). The species has two essential site requirements: the presence of solitary bees (because its own larvae feed on the larvae of the bees) and of the spring wild flowers which the adult flies visit for nectar. These requirements may be met in a wide range of habitats, including urban parks and gardens, but are not so easily found across intensively farmed countryside.

Dotted Bee-fly at rest.

Although it is much less common, Bombylius discolor (Dotted Bee-fly) can also be seen in Gloucestershire. The two species are difficult to distinguish unless the pattern of dark markings on their wings can be seen clearly.

Last year it occurred to me that churchyards might be good places to search for bee-flies, particularly in the Cotswolds where some village churchyards provide oases of semi-natural vegetation within many square miles of agricultural land. This year I am continuing to explore this idea during the flight season of the adult bee-flies, which are active between March and June.

A tightly mown churchyard – but bee-flies inhabit a marginal semi-natural strip.

Sadly, even some of our most picturesque rural villages have churchyards in which the only natural vegetation permitted is tightly mown grass. The solitary bees may still make use of some of these places, but they are unlikely to attract bee-flies in the absence of unmanicured corners where native flowers can grow.

A corner of the most floral semi-natural churchyard I have found.

On the other hand there are churchyards subject to less intensive management (either deliberately or thanks to benign

neglect) where springtime flowers can flourish; my experience so far suggests that, with a little patient searching, the Dark-edged Bee-fly can almost always be found in such places.

There are also, of course, intermediate situations, such as a spacious, mown grass churchyard I have visited where several trees have been removed in the recent past, but the ground flora of violets and celandine that they once sheltered is hanging on; presumably the surrounding grass will eventually overwhelm these flowers, but for the moment they are still attracting bee-flies. Unsympathetic management is an obvious threat to the flora and fauna of our churchyards; perhaps the presence or absence of bee-flies could play a part in assessing their wildlife value,  in both rural and urban parts of the county.

Heaven for bee-flies, bumblebees and other pollinating insects – another corner of that very floral churchyard.