Saturday, 8 April 2017

Birding Forecast

A high pressure dominated weak ahead firstly with a southerly airflow and then switching round to a northerly airflow. 

 Spring overshoot weather today and tomorrow- a southerly airflow drawing from Southern Europe which could bring southern scarcities such as Black-winged Stilts, Southern Herons, Quail etc. Maybe a long shot for London- more likely to concentrate in south east Ireland/south west England. Not great for grounding migrants but is good for migrants arriving to their intended breeding areas/ staging areas- great conditions for migrants but not so great for birders unless luck in with an overshoot. 
 By Monday a cold front moves across quickly- could be good for dropping migrants - the change in wind direction and the front could be good for a drop. Could affect London and Beddington .
High pressure with a northerly airflow takes control mid-week and according to the long range forecasts is maintained. Good for raptor passage with a light head wind.

Raptors: Good numbers of Buzzards, Red Kite and possibly scarcer migrants such as Marsh Harrier particularly from mid-week onwards.
Passerine/landbird migrants: Monday could be best. Maybe a chance of a scarcity- Redstart, Ring Ouzel or Gropper?  Still waiting for Wheatear numbers to arrive. Sedge and Reed Warblers, Whitethroat etc should be arriving soon and common spring migrants such as Yellow Wagtail could be in the game. In high pressure conditions the summering migrants should be arriving through the week.
Waders: Not a lot to make them come down- maybe Monday? Might get a bolt from the blue- especially with a spring overshoot on the long shot cards.
Terns: If moving will mainly head high to staging posts in these current conditions.
Waterfowl: Maybe Garganey anytime.
Gulls: Numbers should be decreasing now. Maybe Med and Little Gulls moving- even in high pressure- best to check high into the blue and listen for Med Gulls calling at height.
Seabirds: Maybe Kittiwake- had a few from the blue in the past this time of year.


Peter Alfrey said...

So far (Monday 10th) Rock Thrush, Red-rumped Swallow, Sub-A on Scilly, Cattle Egret influx in West Country- so a good call on that one
The frontal conditions forecasted for today did not materialise into much so not much happening there
Little Gulls, Sandwich Terns and Little Terns have been recorded at well known inland staging sites across country so a good call there too

Peter Alfrey said...

The front moved across later in day and looks like did drop a few migrants- 3 Wheatears at farmlands pm, also hirundines came down and a good scattering of Ring Ouzels and Redstarts across country and a few other migrants in London.

Peter Alfrey said...

Tuesday 11th was good for raptors with good numbers of Buzzard at Rainham and also an increase at Beddington. Also Reed, Sedge and Whitethroats did arrive as predicted. Overshoots continued to arrive nationally too with a new Black-winged Stilt in the west country. So all in all a completely spot on birding forecast :-)

Looks like weather forecast has changed now to a westerly airflow along the northern flank of the high pressure then to a moderate north westerly with cold fronts - probably will put the breaks on for migration somewhat.

Peter Alfrey said...

Wednesday 12th April -instead of the north westerly putting on the brakes there were significant falls of migrants at Portland and other migrants elsewhere- so a north westerly clearly not a migration killer I often think it is.
Also a good scattering of migrants in continuing westerly airflow until 14th.
With such a busy time of year presumably a lot pushing through even in unfavourable conditions.