Phyllonorycter species at Dene Park

Interesting to think about leafmines at this time of year.

I found some nice blotch mines on the upper surface of Hornbeam leaves at Dene Park this afternoon, which I thought must be mines of a Phyllonorycter species from their "general look". The most likely species should be Phyllonorycter esperella, (Goeze 1783), according to the pictures on the leafminer website. The species has an old synonym, Phyllonorycter quinnata, (Geoffrey, 1785).

Phyllonorycter esperella mines are generally found first in June, then again in September-October, specifically on Hornbeam, Carpinus betulus (L.). The young mines are roundish, on the upperside (generally unusual for a leaf-mine), usually centred over a side vein, silvery with brown speckles, and they then expand to be larger ovals, often substantially contracting the leaf beneath them as they do so. All these characters seem to fit very well the mines that I found today!

The adults emerge, like many other Phyllonorycters, first in May and then again in August as a second brood.

I don't think it could be Phyllonorycter tenerella, as although this species is found on Hornbeam, it is described as being on the underside of the leaf, from the midrib to the edge of the leaf, and quite narrow, generally between only two veins.
http://calderdalemoths.blogspot.co.uk/2008/09/phyllonorycter-tenerella-challange.html

Equally it is very unlikely (but not absolutely impossible) that it should be Phyllonorycter ulmifoliella, which normally feeds on the underside of Birch leaves. There is however one recorded instance of this species feeding on the upperside of Hornbeam leaves, noted in the Entomologists Record of early 2013 following the emergence of an adult from a mine collected in the autumn of 201.?

I also do not think it will be Phyllonorycter messaniella, as that is generally found on Oak, Beech or Sweet Chestnut,  and less commonly on Hornbeam. On Beech and Hornbeam this species is found on the lower surface between two adjacent veins, with a sharp fold, so again this does not really fit the majority of mines found. However there was one mine, clearly different, and I thought it was most likely to be this! It started well out from the midrib, and finished well before the leaf margin, and fitted the pictures really quite well.

Black tern at Cliffe again, even better views.

A good day, although a little bit wetter.

About 1,000 Avocets, 300 Redshank, 150 Black-tailed Godwits, 80 Lapwings, 70 Great Crested Grebes, 80 Little Grebes, 1 Pochard, 1 Tufted Duck, 12 Wigeon, 4 Shoveller, 40 Teal, 15 Mallard, 4 Cormorant, 3 Grey Heron, 1 Greenshank, 10 Greater Black-backed Gulls, 10 Herring Gulls, 40 Black-headed Gulls, 30 Dunlin.

It was lovely to see the Wigeon arriving, circling and whistling, and then settling.

And 1 Black Tern, flying well, steadily and buoyantly in the still conditions and regularly swooping down to the water surface and just the beak touching (in an on-line swoop straight ahead), possibly to drink??

Still plenty of Bumblebees and Dragonflies and a warm day!

Black tern at Cliffe

A much nicer afternoon than morning, so after getting a whole load of College admin done before lunch I headed off to Cliffe pools with Monty. On the Radar viewpoint there were about 200 Black-tailed Godwits, 12 Little Egrets, 20 Redshanks, 3 Greenshanks (including the one-legged bird), 20 Great Crested Grebes, 15 Little Grebes, and some Black-headed Gulls. Across on the Ski Pool there were about 70 Shelduck, 49 Avocets and some Greater Black-backed and Herring Gulls amongst the Black-headed Gulls.

And then I saw a Black Tern over the back of the Ski Pool, noting the quite even grey of the uppersides, the grey breast smudge more visible in flight, the white forehead and black cap, and the slightly forked tail. I was also struck by the generally easy and steady flight, not making a lot of ground speed, quite bouncy and occasionally twisting and swooping down to close to the water surface and then back up again. I now think that it would have been taking insects from above the water surface, although at the time I thought that it was searching for fish and failing! This all ties in with its reported diet, mainly insects but also with small fish and amphibians on the breeding grounds and a mix of insects and fish on migration and on the wintering grounds.

After a while I trailed up towards the flamingo pool lookout, and saw the Black Tern again (unlikely I think to be a second bird), and this time it also settled on a distant rock at the near end of the Flamingo Pool.

On Flamingo there might have been another 30 Coots, 40 Great Crested Grebes and 30 Little Grebes. I also got a fleeting glimpse of an odd duck that might have been a Wigeon in eclipse.

A birder coming back from the Thames told me that there had been another half dozen black terns going West up the Thames. This seems to be a fairly typical movement for this species - I wonder where they are all heading for? Birds regularly migrate Westwards from Europe into England in the autumn (but are less regularly seen on the return trip). Presumably they then head South down the coast of Europe and perhaps the Atlantic coast of Africa to their wintering quarters along the Western African seaboard, centred in the Gulf of Guinea. Juveniles may often accompany them, but may not make the return journey for 2 or 3 years.

The Black Tern, Chlidonias nigra, is spread across the Paleartic, with the nominate subspecies nigra breeding in Eurasia and wintering in Africa, while the subspecies surinamensis breeds in North America. They tend to be fairly gregarious and can commonly be found in groups of 2 - 20 on the breeding grounds or on migration. However they can also be found in much larger aggregations of up to thousands in certain migration points, or in Africa. Some birds may move South down the Nile and Rift valleys, perhaps wintering around the Sudan.

Spring migration of adults begins in late March, mainly via the West African coast. On reaching Spain many birds may move along a Mediterranean route while others follow the Atlantic coast, of which some may be seen in Britain. The "Sudanese" winterers come back up the Nile, and may join the main stream of migration as some of them on the Mediterranean route move Eastwards along the Northern coast of Africa before moving across to Eurasia.

The breeding grounds seem to be under some threat due to habitat loss, but the species is not declining fast enough to be considered threatened (by extinction). Interesting that the species can be declining and generally disappearing from specific areas, but not thought to be under threat! The birds arrive in a group at the possible breeding area, and explore it, finally settling to jointly build the nest - a pad of vegetation on the marsh or water or a scrape on the drier ground - and laying only about 3 days later. There are some great behaviours described in BWP, and overall it is a fascinating bird.

Courtship is primarily monogamous, at least for the current season. Courtship is both aerial and ground-based. There is generally only one clutch, of 2 - 4 eggs which take about 21 - 22 days to hatch. The young are precocial and nidifugous. They are fed by both parents (up to 80 times a day), and also brooded for the first week or so, staying in the nest itself for only 2-3 days, then wandering further as they explore the area around the nest site, and then heading off into the surrounding vegetation.  They start to fledge after about 19 days and are capable of independent feeding and then flight from about 25 days old.

Oare Marshes

3 or 4 Ruffs, Philomachus pugnax, some juveniles, 1 poss adult. 500 Black-tailed Godwits and about the same number of wonderful Golden Plover. Dozens of Teal, some Shovellers, a few Redshank, about a hundred Lapwing, all on the main scrape, an amazing place to see birds close-up. No photos unfortunately.

Warmer Cliffe

About 500 Avocets, 500 Black-tailed Godwits, 20 plus Great Crested Grebes, same again of Little Grebes, at least a dozen Little Egrets, a few Redshanks. 

Cooler Cliffe

400 or so Avocet (fantastic site wheeling about), 100+ Redshank, 50+ Lapwing, 20+ Great Crested Grebes, 15+ Little Grebe, 60+ coot, 2 Goldfinch, 20+Black-headed Gull, 3 Black-Tailed Godwits.

Warkworth Sunday

Fantastic walk along the beach. Sandwich and I think Common Tern, Common and Artic Skua, Black-headed Herring and Lesser Black-backed Gull, Redshank, Curlew, Turnstone, Curlew, Dunlin, Red-throated Diver, Eider, Cormorant,

There were about a flock of about 50 finches in the dunes inland of the beach - I hoped for Linnets but the could all have been Goldfinches.

After I trudged quickly back down the beach South to the old harbour, little more was seen until I reached the river estuary and followed the muddy offshoot of the Coquet (locally known as the Gut, I think) towards the dune slacks overlooked by the picnic site where I had left the car. On the Gut itself there were Black-headed and Herring Gulls, lots of redshank and a single curlew. I saw one Lapwing overflying, but the walk had now turned into a bit more of a route-march to try to get back to the house at a reasonable time - and to have some breakfast!