Thursday, September 25, 2008

Herons Yesterday 24-09-2008

Hi Clive

Very interesting that you also had migrating Grey Herons yesterday down the east coast. Grey Herons going over in flocks here at Oxenhope are very uncommon..... they must like the anticycloinc conditions to move in. Did your groups of Grey Herons look anything like these four moving NW in a single very tight group?

I montaged 5 snaps together to save on sending individual photographs..... each group of four birds is a single snap showing the birds as they approached, went past and away.

Montage of five snaps of a group of four distant Grey Herons moving > high NW (c) 2008
Click to make it Bigger!

Same four Grey Herons going past > NW (c) 2008

Grey Heron > NW (c) 2008

Hi Dave

Yes my Grey Herons looked exactly like yours – although I forgot to photograph them! Perhaps we would see more herons if we spent more time at our watch points during high pressure systems. Sadly here in Britain there generally just aren’t enough big birds (raptors, herons, storks etc) to justify the amount of time it would take. Having said that, sits on the south coast do a lot better than we do further north, not surprisingly.

The Trektellen graph for Herons at GB sites shows that there is a marked passage period during the last three weeks of Sept. Graph for Grey Herons at UK migration sites
Click to make it bigger!

for this and graphic representations of other moving species in both this and other European countries.

The map in the BTO mig atlas shows a lot of movement from Scandinavia in a SW direction across the North Sea, UK and some across the Irish Sea and the time of year now ties in with with this movement described. The topography here at our watchpoint at Oxenhope is such that it often channels westward and even SW moving birds NW as it passes us so i wouldent put too much reliance on the NW direction which may well have been locally induced.

Clive and Dave

Oxenhope 25-09-2008

The Long Wall......Fog Stratus again at Dawn (c) 2008

Becoming Shallow Fog by 0735hr..... vertical visibility to Altocumulus perlucidus upper cloud (c) 2008

E F2 reducing E F1, 11.5degC rising 11.9, 200m - 2km, 7/8 Shallow Fog Altocumulus perlucidus, QNH 1033 rising.

A very poor morning for the vis.... when are these anticyclonic conditions with easterlies going to move off!!!!......Initially deep fog stratus but soon improving to shallow fog with good vertical visibility by 0735hr when the first Redwing of the autumn could be heard seeeping as it passed high overhead. In addition to this there was much activity above the fog this morning but most was visually out of reach just above or in the the fog top. Large groups of mipits were constantly heard going over but few could be counted. Albas, Chaffinch, Siskin and a few Redpoll were doing similar. Movement however was short lived and by 0815hr deathly silence prevailed in the quietening wind, punctuated only by the odd party of birds going over. By 0915hr the ceiling had closed and the fog was drawing in again, thus it remained until the end of the visit.

Moving birds in order of appearance:

Goldcrest calls from the fog upon arrival.
Meadow Pipit 156 > various
alba wagtail 18 > various
Chaffinch 14 > various
Redwing 1 calls heard
Siskin 4 lots heard > SW
Redpoll 3 lots heard > S
Reed Bunting 1
Goldfinch 66 > S
BH Gull 124
LBB Gull 7


Wharfedale 24-09-2008

From 1100hr and PM
No Vis-mig observed as such, but interestingly, still plenty of Mipits blogging over the moor plus a fair number of hirundines blogging over the valley and fell.