Partly explaining why a.m. radar often shows different directions for birds still completing broad front flight at height when compared to low-level vis-miggers. Sadly, Low Countries BirdTAM best 'alarm' for you at mo'. (Many wind farms have radar they don't share either. Shame.) HOI 4/4

Many spp. migrating at mo' fly mainly during 1st half of night, vols dropping after midnight as 'settle' (per Newton) only to restart c/ol vismig flight starting hr b4 dawn, for couple of hrs before wind turbulence builds. 3/4

BirdTAM is military, not freely/easily available in all countries e.g. UK & Norway, & Denmark since '08 - see fig, before/after. Note more German availability. Some E Anglian arrivals do arrive via Southern Bight crossing of N Sea or Channel and then overflying Kent/Essex. 1/4

Making up the pension shortfall w/out using annual subs has meant pain the last few years. And goes some way to explaining the job cuts announced back in the summer. However it is spun, they're still saddled w/ finding savings for a few more yrs.

The Nutcrackers have arrived , not the ones I wanted...

Ah, desire paths. I love 'em. "Desire paths have been described as illustrating 'the tension between the native and the built environment and our relationship to them'. ... they can be seen [as] a way for 'city dwellers to ‘write back’ to city planners, giving feedback with their feet'."

Why a dedicated patch worker, saying waders *appear to be in freefall*, freaks me. Had me thinking on vismig usefulness as still dismissed by some as "The sky numbers are falling! The sky numbers are falling!" Should we listen? A short series of daily threads follows.. (you have been warned🤔😉)

If right, as a major Greenshank estuary, decades of going wrong here may have influenced national upward trend a tad. Accuracy. Precision. Too late for robust long/ medium- term trends for here now? Knock-ons for national level? And common spp.?

E.g. I could do a whole thread on Redshank. As soon as back I knew where probs were in our data, but taken until recently for whole estuary count to get back close to cum. tot. for what is often shore alone.

Greenshank, in it's low nos, should be an easy spp. to spot trends in data/ real life. Are trends harder to spot in common spp? The bread and butter one on passage, many why an estuary protected. Certainly our big bucking of trends was highlighted in past. We've didn't have a grip here.

We still have no grasp of core wintering nos for here. Greenshank in Aug-Oct, will include many moult/short- stagers (some just now moving on). We have no official idea of their actual number either. Trends are well out, and we're no. 2 estuary.. How many other estuaries have similar probs?🤔

In passing, can be many other li'l contributory errors. Eg locally, Greenshank in my pic are in sector said to be counted. But w/ nil counts since 2017. Not no birds present, no counts allowed by landowner. Even if had complete coverage here, might not necessarily be complete. Devil in the detail.

When I moved back I compiled published annual County monthly max figs as start point for w/ what was known. Did as heat spreadsheets, here pulled up actual figs Sep-Dec. Told me no real long-term trends on display. At same time other locals told me were there, just undercounted.

Let's return to that English 'winter' graph upswing. If main 'winter' definition, Sep-Mar (Core 'winter' months: Nov-Feb, Int'l reporting month: Jan) Autumn passage tops core winter nos. Point is, varying effort irt most important estuaries could have big impact on trends.

Now, let's look at all main estuaries , c/o old 5 yr avg vs current. Those that have declined over the years are highlighted. A lot going down. Of course, difficult to compare. Efforts change, co-ordinated amount changes, etc, etc.

Now, let's look back to when I started watching the Medway nigh-daily.. Back then, a much, much lower (incomplete) average.

Ask the WeBS not to show supplemental results, Medway has to have avg calculated on incomplete counts (still top in county). Look at Thames. Has a complete count. Uses that. 41/1 = 1 (Accuracy/precision. Part of why I used to bang on about incomplete coverage..)

Let's focus on Medway Greenshank and WeBS. Publicly viewable results make for interesting reading. Last 5 yrs' average WeBS, Medway top in Kent. C/o supplemental count (that's a count not made on WeBS date). All other yrs in brackets. = Incomplete counts so not used to calculate avg: 120/1 = 120.