Horrid autumn- 2/10/17

Geography Lesson: saltmarsh creation to the west of Horrid,
open water to the east.

7:00-11:00
Viz mig: Marsh Harrier 2, Kestrel, Lapwing 25, Sandwich Tern 23, Common Tern 11, Swallow 10, House Martin 8, Meadow Pipit 88, Rock Pipit 2, Pied Wagtail 11, Linnet 70.

Point: Green Woodpecker, Cetti's Warbler, Linnet 16, Reed Bunting 2.

Offshore: Peregrine hunting Redshanks. That never rocks my world as much as many others who enjoy a hunt and a kill. I'm more about cheering on the underdogs. Besides, that bird was spoiling the ballet. Watching waders assemble like watching ballet; beautiful, but it helps to know what the movements actually mean. Today's subtle backstory was among the tracks of birds from Ham Ooze and other points west; addition numbers joining the western basin cast, following weekend wildfowling by their preferred roosts. Monday matinees often give you a show you didn't expect. Today's map? Stage directions for the Grey Plovers.

That other story, that Pergerine? Well, she succeeded at the second attempt, managing to flush part of, then the remainder of, the Redshank roost on Rainham Saltings. Both groups headed off fast and low to Motney Saltings. Many not to the main roost along the northern edge, but spread along the southern saltings. It was almost as if they were watching back to Rainham; after 25 minutes, about 60% of the roost flighted back, circling twice before going in. Why? They could have roosted on Motney with the rest- the site can hold higher numbers on a busy tide. Perhaps, just perhaps, these birds wanted to be back to take the prime feeding opportunities at Rainham Saltings as the tide drops? Often largest return movements from Nor, Friars, back to Rainham happen after a few birds have made their way back; rather like the doves and ravens leaving the Arc, no leaving the safety of the roost until sure. Then it's a big percentage rushing over. Some days they jump the gun, and have to come back. Today, good luck to those that risked moving back early. After all, the early wading bird gets the most ragworms.

Reflections

I'm torn. My favourite man-made landmark on the estuary gets blown to kingdom come in the morning, and I really haven't made up my mind whether to watch the fall of this old friend or not. You see, not only do (did) I look at it every day, I have been lucky enough to look down from the top of it a couple of times.

The external safety lights needed routine inspection, and the sparkies had passed comment on the number of dead birds behind the fittings to the Environmental Initiatives Officer. Having passed the medical to say fit enough for the stairs, I was allowed to accompany them on their trips. The two poor quality snaps reproduced below are 'x-rated' record shots of, first, the number of corpses that could be recovered on one six-monthly inspection and, second, the chimney nesting platform so thoughtfully provided by the owners but being used, rather ungratefully, as a larder, by the birds responsible- Peregrines.

Contrary to many birders' beliefs, the Peregrines never actually nested on the chimney- that was some distance elsewhere, but the chimney made for a great hunting perch, towering some 802 feet over a dozen "football stadium floodlights" which lit up the entire site all night long, making passing birds easy targets. The peregrines could be busy at night, often to be heard on the wing calling, by the small team of bird ringers arriving to set nets pre-dawn.

When their feeding was good, the breast meat might be all that was taken or, sometimes, just the brain. The adults would also bring their young to the chimney to teach hunting skills by having them fly out to snatch a deliberately dropped kill. So, while the older corpses were a matted mess to try to identify, any fresher kills were much easier. Waders featured highly; Woodcock, Snipe, Jack Snipe, Lapwing, Golden Plover, Knot, Dunlin... Water Rail and Little Grebe also featured, land birds included Skylark and Quail, Little Tern was on the menu, and, much to the annoyance of some, even a rarity, a male Little Bittern (not much chance of that plumage sneaking past under the floodlights).

40 plus species noted on my visits if I recall correctly- though my notes are long gone, and the ringing station logbook is probably somewhere in storage gathering dust. The records were copied in to the county ornithological society at the time, though full details never made print, as station security was on 'high alert' due to terrorist threats. Part of the visiting arrangements were that the ringing team had to avoid publicity and not attract 'extra public' to the fenceline (though news of the Little Bittern did go out some time after the event to provide a story at the time of the first 'No Aiport at Cliffe' Campaign- no birder really wants to 'tick' rehab birds, yet alone one way beyond any veterinary help).

Great memories. Certainly cured me of my fear of heights. What the heck, the chimney is on north side of the estuary and I do only bird the south side nowadays- I will go and watch it fall. Maybe.

The view to Allhallows

Grain village

Smithfield Marsh

2002, 244 metres up

2016, one metre down

An estuary retreat

The Dunlin departure was apparent from just before mid-month. In the eastern half of the estuary, the roost numbers dropped and for the remaining birds very few now followed with the tide- it was almost as if the falling pressure of numbers allowed the smaller flocks to feed more leisurely.

This effect was the same in the western half, but not as apparent to the casual observer, as numbers loitering on the flats close to Rainham might not, at first, have seemed to have dropped. But close to this prime area, Dunlin using the flats east of Horrid Hill were greatly reduced, and fewer flocks could now be found out mid-channel. Birds that remained were not moving far. Correlations/causations- certainly the second half of the period was notable for some particularly slack neap tides, helping stop the Rainham flats from draining quickly, but it was also noticeable the birds were choosing not to roost so further away, largely giving up on Bishop and using the nearer Friar's saltings instead. Reasons can only be guessed at; e.g., could the antics of the gulls re-establishing on Bishop now be having an effect? Why risk moving a tad closer to the two young Peregrines often seen loafing on Nor? The roosting Dunlin were certainly being put to flight more often, heading south-west to Motney saltings, which they had ignored for the greater part of the winter.

Questions, questions. Including, of course, 'so how do the numbers compare?'

As before, these numbers for the south Medway are merely a representation, impossible to simply 'add up'. If I had to offer a considered opinion, I'd estimate a drop of about 50-60% between periods. Now very interested to see what changes the third period brings.