Warning: adult content- Shags on the Medway

As a starting point for this blogpost, Oliver's 'Bird Watching on the North Kent Marshes' is a good place to begin- his summary for the whole of the Marshes fits published records for the Medway in the 21st century "one or two individuals are reported in almost every winter... they favour the tideway in the Medway... most are from September to March, with a preponderance in mid-winter. There is no evidence to suggest that the increase in records is attributable to anything but an increase in the number of observers..."

Is that right?

Most local birders catch up with the bird when an individual takes a liking to the ready food source held within the Chatham Maritime basins, suitably served in a decent depth of water all day long. Up to the mid-eighties these basins were out of bounds in the old Chatham Dockyard Naval base, and Oliver was published in 1991.

Are there still Shags to be found on the tideway? Simple answer, yes. Thanks to being in the position to visit the estuary almost daily, that can immediately be revised to an annual visitor. To find your own, once again you have to think about food and roosting.

The old records point to deeper creeks, with no mention of tideway state when seen- Motney (so, Bartlett Creek), Greenborough/Stangate Creek and Kingsnorth (Damhead Creek, Long Reach). The comments under Cormorants regarding prey concentration during the running of the tide apply equally well here: a bird can be found actively feeding, a bird might be found hauled out on the rockier flats over the lower tide. 'Might', because they can often choose to use their favoured high tide roost, or go elsewhere to continue feeding.


Safe roosting

The Kent Bird Report of 1996 draws a conclusion that four Shags visiting the basins were the same as four seen roosting some four and a half kilometres away. Fair conclusion? Never seen moving to and fro, but much of that flightline is underwatched. The roost, the Oakham jetty at Kingsnorth, is one of the few Shag-friendly roost sites on the Medway. They do not join the Cormorants a short distance east on the crumbling metal framework of the Bee Ness Jetty; Kingsnorth is more substantial, designed to take traffic and made of concrete with, thanks to the support design, a series of suitable roost ledges tucked just under the roadway. Roosting birds can be well hidden, and were often only found by leaning out and scanning a long way back along the jetty.

In recent years when asked why a basin bird might be missing, I have suggested only really down to lure of easier concentrated fishing in the creeks and that a middle of the day search, especially around the high tide, is the best way of guaranteeing a good chance to tick-and-run. Over the tide, even if well-fed and looking to day-roost, buoys on the calmer waters right next to snackfood beat returning to the main roost.


Occurrence

It is fair to say Bill Jones has seen more Medway Shags than any other birder, thanks to his years as Environmental Initiatives Officer at Kingsnorth Power Station. His assessment of Shag timings for the Medway differs from that published- most have occurred around Oakham/Kingsnorth in early-/mid-spring, notmid- winter.

With most observers only having Shag on their 'radar' in winter, just as there are fewer birders on the Medway in the spring, there are fewer searching for them (sightings are often far from the shoreline). Even so there are March, April sightings popping up in the records, including from recent bird cruises on mid-estuary.

As discussed in several old blogposts, this estuary is 'non-coastal', so 'migration' often go undetected- late autumn movements such as those recorded from time to time on the north Kent coast do not happen.

Taking the North Kent Marshes as a whole, Shags have turned up in every month of the year (an exceptional story follows below) so they should never really be off a birder's radar. They do vary in numbers from year-to-year, which is most likely down to food abundance elsewhere; many do not bother to move that far from breeding areas- they just need to move on to the next easy fishing.


Origins

Ringing recoveries trace many Kent birds back to coastal eastern Scotland. Fewer Farne Island birds move as far- the Scots leapfrog them. Perhaps island fishing is better? Certainly onshore winds make fishing harder, and prolonged strong easterlies force Shags along the coastlines.

They do not come from the continent in any number. As per Cormorant, they do not like leaving sight of land- they need to haul out to dry off, so better to locate new feeding close to shore.


Are we really seeing adults?

In describing plumages some forty years ago, the first volume of Birds of the Western Palearctic used a phrase now out of favour- 'first adult plumage'.

Shags usually do not breed until their fourth year. Now another Shags can tell an age easily, but can struggle after the first couple of immature years. The problem, left out of many of the guide books, is the three year olds. As BWP went on to explain this first adult plumage is "acquired gradually between second and third autumn; some specimens, however, like adult in March of third calendar year..."

So, a third winter youngster, one not set to try breeding until the spring, may well look like an adult.
To ramp up the problem, the recent 'Identification of European Non-passerines' by Baker, seems to say this is a real problem. To quote,  "3w- most not ageable but a small percentage of birds (2% of males, 4% of females retain (an immature type) outermost primary until summer of fourth calendar year."

So, us southern softies, with our limited experience of Shags, and certainly not that many close up views, have a habit of going and claiming 'adults' when we often might have no way of ruling out a sub-adult (and probably never consider that age).

Does this really matter? Well, if you want ot publish official records as adults, yes. Philopatry. In rough terms, in many non-passerines long-lived species take several years to mature; they might not migrate routinely during their lifetimes. A successful adult will often winter close to the breeding grounds if food is available. Out-competed, outranked youngsters have to move. They may stay at a chosen wintering site first year, they might venture closer to natal breeding grounds in second summer and they might even stop awhile at the start of the third breeding season, but they are recognisable to adults and usually not taken on as 'risky breeding stock' unless, say, something has happened to a chosen mature partner just as the colony reassembles.

In Shags, variability in feeding can lead to varying numbers of adults moving more often in some winters, but for anyone trying to study Shags in the south-east any apparent increase in adult numbers does not reflect any real change in adult patterns- they are still not likely to go further than they need to. But read the bird reports and it seems adults are visiting. It is just as likely to be immature birds finding our recovering waters more suitable again. Ringing recoveries do show that adults are appearing, but we cannot presume adulthood as easily as we do.

Chatting with Bill Jones on the Kingsnorth Shags, he certainly wondered if any birds hanging on into spring on his artificial ledges along Oakham jetty signalled older youngsters with increasing hormones. Could loitering third summer birds ever lead to a claim of possible breeding?


The Kemsley young 'uns

A nice published history from older Kent Bird Reports from the neighbouring Swale:

1991- "two wintering in Ridham Dock in the last quarter"
1992- "in the north three first year birds were resident on the Swale at Kemsley to June, with two second years then remaining to year end"
1993- the two remained at Kemsley throughout the year and were joined by four others from Nov 18th to 28th"
1994- birds were present at Kemsley... for most of the year, with numbers increasing from one in January to six by Feb 12th, with peaks of three in March, six in April and four during July to October"

Now that is something- a great chance to have noted all these different Shag plumages through the years here in north Kent; juvenile/first winter changing to the paler first summer to the off-adult second winter and then into the more confusing second summer. I'd opine there'll never be anything as rare and exciting as that around that part of the Swale- though I'm sure others would disagree with that this very week.

Okay, so I might have to let that slip. But do expect a few hard questions if you try to tell me a Shag on view on the basins is an adult.

An eminent Shag researcher writes

Thankfully, this e-mail does contain some birds and some estuary (although more central and north estuary than I like).

Once again the e-mail in-box has been dominated by a Mr Trellis of the Gower, south Wales (I really hope he works out the 'comments' button here one day soon). It followed my recent post on Cormorants and the promise to follow up with a short note on Shags on the estuary.

Mr Trellis kindly supplied me with a photograph he took some years back at Kingsnorth, on the northern shore of the Medway. Birders will instantly recognise Shags, local birders might also recognise a youthful Bill Jones.

Two ridiculously tame young birds came to recognise the stench given off by Bill, prone as he was to collecting specimens from the Power Station intake grilles (leading to a massive fish species list for the site, a story for another day). Actually, the smell may have been his specimen bucket, we were never too sure. Over the course of a few weeks the birds came to appreciate both Bill and his bucket, which in turn led to their gaining BTO rings. There is no such thing as a free lunch with Bill.

In addition to the photograph, Mr Trellis supplied me with some interesting observations on Shag behaviour and timings for Kingsnorth and Nor, so I really have no excuse for not finishing the note. Watch this space...

------

(Bill and his bucket have featured before, see this Little Egret story)

An eminent geneticist writes (Rise of the Planet of the Geese, part two)

**Caution- this blogpost contains no birds and no estuary**

Two e-mails stood out in the other morning's in-box. In the first, an eminent geneticist, a Mr Trellis, PhD, MSci, of The Gower, South Wales had taken the time to comment upon the recent Haldane's Rule post. In the second, an eminent geneticist, a Mr Trellis, PhD, MSci, of The Gower, South Wales had taken the time to comment further upon the recent Haldane's Rule post.

I have been provided with links to two rather interesting articles from 'Science'. The first hinted at how species hybridisation has played an important role in evolution, even in our own history as we all carry genes picked up from from inter-species shenanigans with our old relatives the Neanderthals and the Denisovans. The second was a link to an article by the same author concerning a hybridised population setting off on the path towards a new Galapagos Finch species within our own lifetimes.

So, thanks again to Mr Trellis for putting me through my paces. Of course, Haldane's Rule is just that- a rule. It is there for guidance, unlike a law, which is there to be broken. The majority of inter-species offspring follow the rule. Of course, I'm no geneticist, so take (perhaps too much) heart in wikipedia and the like, but do note from the first article not all professionals are in agreement as to the importance of such hybridisation in the evolvution of species. (The article omitted to mention that the jury is still out on whether Neanderthals and Denisovans were actual species or simply sub-species.)

The finch study is also fascinating, one where the hybrids have been fertile and gone on to choose to breed with other hybrids, but those that carried out the study are cautiously holding back from calling this the start of a new species. Within the example these hybrids found themselves in a short period of isolation thanks to a drought on their island. The setting for such a swift change is not one likely to be duplicated in the example that brought my original post- hybrid geese latching on to members of a much larger widespread wild population.

I should admit Trellis has been trying to educate me, with little success, for about 30 years now, and I'm lucky he perseveres. On the species concept, we already agree that evolution does nothing to make it easy for us to force all into neat little tick boxes. I'm secretly expecting another e-mail in the near future, following the recent decision of the British Ornithologists' Union to adopt the IOC list and the long, long awaited re-lumping of Lesser and Mealy Redpoll,

A Redpoll, of sorts

An eminent astronomer writes (A twilight saga, part two)

**Caution- this blogpost contains no birds, and no estuary**

One e-mail stood out in my in-box (as, obviously, as it was the only one). An eminent astronomer, a Mr Trellis, MPhys, MSci, of The Gower, South Wales, had taken the time to correspond upon the recent Twilight Saga post.

Their' source of information was Norton's Star Atlas (the amateur astronomers bible), and provided some excellent specifics. I quote:

"Twilight from ancient times, has been reckoned as ending when the the Suns centre is 18 degrees below the horizon, 6th magnitude stars then being visible at the zenith; it has no definite duration, however, as meteorological conditions may modify it. The glow, in its later stages is a segment of a circle , brightest vertically over the sun. Directly opposite the indigo-blue segment of the unilluminated atmosphere rises from the east as the sun recedes from the horizon.

"Twilight lengthens with distance from the equator, and is shortest all over the Earth about the equinoxes. The total variation never exceeds half an hour below latitude 40 degrees, and in higher latitudes, some 10-20 minutes during autumn, Spring, and winter; but above Lat 40 degrees, in summer twilight lengthens, till it lasts all night above 50 degrees. Civil, Nautical, and Astronomical (British Nautical Almanac) end when the sun's centre is 6, 12 and 18 degrees below the horizon- the first about the limit when "ordinary outdoor operations become impractical without artificial light" "

I have written thanking Mr Trellis for this new information. He continued by providing some specific timings for twilight duration at several latitudes, including:

Latitude.                                                Winter solstice.       Equinoxes.       Summer solstice

50 (a tad below London)                       1hr 59min.           1hr 50min.          Lasts sunset to sunrise
55 (around about Edinburgh)                 2hr 17min.           2hr 4min.                                  "

------

Having lured me in, Trellis then delivered his sucker punch. It appears knowledgeable astronomers insist twilight occurs only at dusk, never at dawn.

Had I upset the professionals? I'm no astronomer...

It called for some etymological research:
twilight (n.) "light from the sky when the sun is below the horizon at morning and evening," late 14c., a compound of twi- + light (n.). The exact connotation of twi- in this word is unclear, but it appears to refer to "half" light, rather than the fact that twilight occurs twice a day. Originally and most commonly in English with reference to evening twilight but occasionally used of morning twilight (a sense first attested mid-15c.).

So, used from time to time for dawn twilight for about 500 years.

It called for some ornithological research as well, by turning round and pulling the Poyser 'Birds by Night' off the shelves behind me (and yes, dear reader, perhaps I should have done so on the earlier post). The author is described by some as "the world's leading authority on nocturnal birds and one of the world's foremost vision researchers". Thankfully my initial post hadn't veered that far from his text. Admittedly, it took me to page 83, but there it was- "...passerines involved in morning twilight song..."

So, I am indebted to Mr Trellis for putting me through my paces, and causing me to stumble upon other excellent terms such as 'dusk chorus' and 'zeitgeber*' for the first time. I am aware Mr Trellis attends astronomical conferences at Taggs Coffee Shop at Hoo St. Werburgh from time to time, so I shall have to drop in to purchase him a cup by way of thanks.

* Zeitgeber- a rhythmically occurring natural
phenomenon which acts as a cue in the
regulation of the body's circadian rhythms.

Duck Soup ingredients- (vi) a chinois of Shoveler

Their sieve-like bill makes the Shoveler the most specialist feeder of the dabbling duck, with planktonic crustaceans a mainstay. On the Medway they take mainly hydrobia and some salicornia seed. Through necessity feeding takes place on calm (usually fresh) waters, but is also routine on mudflats, especially on the wettest interstitial mud where prey numbers can be much higher than found in open water- why the Shoveler will often feed close to the footpath at low tide in Rainham Creek towards Rainham Docks East, or just offshore from the Twinney Saltings.

Interestingly, Shoveler often loaf within their feeding zone, unlike most other Anas species which prefer distinct separate areas for loafing.

When disturbed, the majority of birds in the western half make for Friars Saltings or Nor. To the east the Twinney flock tuck into Millfordhope/Slayhills, less often into Funton.

As winter progresses, small numbers spread out and take up with ducks at the other main loafing areas.

In the past very few used the estuary as a feeding area. Now, peaks are usually noted during early winter, after which time poor weather (strong winds on open waters) can see decreased numbers (often reflected by increases elsewhere around the North Kent Marshes). Freezing conditions see birds deserting shallow waters first for the estuary flats, all evidencing why large counts alone might not reflect true carrying capacities.

The main autumn loafing areas are marked on the following map (yellow), together with the two main mid-winter concentrations.

From personal experience, the present five year average peak from WeBS (192) is an understatement of the wintering population. Over the covering/high tide, esturine Shoveler tend to tuck up tightly in cord grass; watch a mudflat loafing/feeding group through the covering cycle and numbers will always be higher when the mud is uncovered. WeBS are high tide counts. A good example why birders on many estuaries around the country carry out co-ordinated low tide counts much more often than the BTO LTC six year survey. Another species where more ad hoc counts by birders can help provide a more detailed picture.

Duck Soup ingedients- (v) a scoop of Pintail

Structurally, the long neck of the Pintail allows feeding at a greater dabbling depth thanfor  other Anas, especially when upending. It is rather unremarkable in diet choice, with most texts quoting a reliance on grass/seed, but here on the Medway food primarily consists of hydrobia, supplemented with samphire and seablite seeds. Pintail will also come to wildfowler/game feeding sites in small numbers, more so in cold weather.

Feeding intensity usually peaks both late morning and late afternoon and is also influenced by tidal state, so loafing flocks on the flats can be at their lowest at these times.

The general winter trend is for a double peak- in October and (more strongly) December- early January, with numbers starting to drop from the end of January. The early autumn birds move on to southern Europe and Africa, later birds staying for the winter. Cold-weather movements are noticeable during freezing conditions.

The map shows their main areas; Rainham Creek, Lower Halstow and Funton provide easiest viewing. The red circles mark the most favoured onshore sites during late winter.

From personal experience, the present five year average peak from WeBS (505) fails to reflect the true number for the estuary. This may well be down to the 'weekend effect' already mentioned in other species accounts; there is more weekend disturbance leading to more loafing numbers retreating to the islands.

Duck Soup ingredients- (iv) a julienne of Mallard

Mallard often stir up little or no interest in birders. Which is a shame, as there are some important questions regarding true numbers of wild birds that need answering.

Mallard take most of their food from the landward side of the seawall- on/around brackish/fresh water, grass or cereal crops. Wide range of feeding techniques for the variety of foods taken. They are mainly nocturnal feeders, so most birds encountered on the estuary are loafers.

Several private feeding areas, maintained by game shooters/wildfowlers, produce the highest numbers at the start and through the winter. It is always difficult to assess how many are 'wild', as some of the shoots release good numbers (in the hundreds)  in the month before the start of the shooting season.

Early autumn peak numbers might be expected to remain relatively stable as shot released stock are replaced by incoming continental birds- however numbers close to the seawall do drop away. It is thought that fewer continentals are now migrating, but the result could also easily be down to a more localised effect as more birds spend longer on small waters inland.

The main loafing areas and flightlines are shown below.

From personal experience, the present five year average peak from WeBS totals of 359 for the whole estuary is well below the early winter peak for the southern shoreline. As a mainly nocturnal feeder with a predilection for loafing in small numbers in cover, WeBS timings are really not the best for obtaining maximum counts. The question of true 'wild' numbers is muddied by releases, and co-ordinated counts in late August would certainly give a better indication of totals involved (again, higher than the present five year peak as quoted by WeBS).

Duck Soup ingredients- (iii) a sieve of Teal

Teal have a specialised technique for sieving and need just a thin layer of water over their feeding ground- why when on the flats they are nearly always found at the water's edge along the creeks.
The most usual feeding method is walking slowly in shallow water, filtering as goes.

The first returning birds in late summer often stick to the flats but start to use inland flashes and shallow pools in autumn where new flooding lifts dropped seed. Esturine feeding more reliable- nowhere is rainfall guaranteed. Spikerushes and Crowfoots are most favoured.

Teal have a lengthy autumn migration, between late June to November. Once settled, birds remain, unless prolonged freezing stops them from feeding in favoured shallow waters. We might then see westward influxes from the near continent, or see 'our' birds move south. If they do leave, they do not return, remaining instead in their new quarters until spring migration from late February onwards. Generally, the peak is December, prior to the majority of cold-weather departures.

As well as the obvious offshore loafing areas (although if you count, often many will be feeding), Teal are very happy in deeper cover, including scrubby reed beds. Motney sewage farm and Motney reed bed, Horsham andOtterham is a good example of a large core zone. Pre-dawn, large numbers will be feeding in the creek and on the marsh. By an hour or so after dawn, many of the birds will have flighted to cover, favouring the sewage farm especially.

The following map shows their main mid-winter concentrations.

From personal experience, the present five year average peak from WeBS totals of  1,563 is an under-estimate of actual numbers present. Early morning counts of loafing areas, before numbers retreat to dense cover, routinely pass this total for just the southern shore through much of the winter. Any counts from birders out early in the day would prove useful data.

Duck Soup ingredients- (ii) a grating of Gadwall

The Gadwall is not really 'esturine'. It seeks still, fresh waters and takes a lot of freshwater material, especially pondweeds. Plant material gathered from just beneath surface, mainly with the head a little under water. Gadwall feed sparingly on land. In late winter may take more seed, then can be found at feeders on the game farms. An interesting behaviour is their routine bullying of Coot. Find somewhere favoured by Coot, you will find Gadwall stealing their food.

Numbers are generally steady through the winter. Single figure counts at individual sites are the norm, though find the safe night loafing site and you can get 20 or so birds together pre-dawn. Another species more common the further east on the estuary you are (the main loafing zones and flightlines are shown in yellow)..

Below the high water mark each winter one or two Gadwall might latch on to Mallard and, when loafing birds are put up, follow them. This leads to one or two being seen out around Nor or Folly Point, and flighting between Bayford and Greenborough.

From personal experience, the present five year average peak from WeBS totals of 45 underestimates the true total, thanks mainly to their skulking behaviour during the time of day most counts take place.

Duck Soup ingredients- (i) a paring of Wigeon

A grazing specialist, Wigeon first rely on pondweeds and algae, becoming more reliant on grasses as a winter progresses. Very much a generalisation, as some individuals might favour grassland, while others might rely almost exclusively on the estuary itself, but certainly between September and November, the vast majority will favour the flats, then switching in large numbers from saltwater to freshwater vegetation from November onwards, as volume of algae drops. What is left is also then deteriorating in quality, making grass is a better energy source, especially when the weather is mild and the growth continues. (This winter it has been interesting to see Wigeon exploit a newly seeded growth on one stretch close to the sea wall.)

Providing there is no hard weather around the time of this switch, although a birder might count fewer Wigeon loafing on the flats, total numbers on the estuary actually remain roughly the same. Birds can choose to feed 'inland' during the day at sites such as Ham Green and Chetney. Although there is a big turnover of individual Wigeon during an autumn as birds use the Medway to stage and refuel before continuing south, unless there is severe weather, perhaps heavy snow denying easy access to food, there are no routine cold-weather movements, just localised redistributions. Individual birds will often use the same areas at similar times in subsequent years.

The over-simplistic map below illustrates autumn/early winter feeding/loafing areas (yellow circles) with an indication of usual movement on the rising tide. They will loaf on or near algae beds, then retreat toward safer areas as needs be.

After the switch to grasses/seed, Wigeon will often feed inland (red squares), retreating to islands when disturbed. If the islands are being shot that day, they might make a small adjustment to another part of the complex (the Greenborough complex is large, the number of guns usually small) or ride out the tide/ sit out on a flat.

To find good numbers in late August/September, look to the algal beds offshore close to the main channel; Copperhouse, Ham Ooze and Blackstakes often provide the largest flocks. Come mid-winter, most of the birds on the mud are loafing; do not forget to check the viewable parts of Ham Green, Barksore and Chetney.

From personal experience, the present five year average peak from WeBS totals of 1,932 Wigeon for the whole of the estuary is passed routinely by just the southern shore. Incomplete counts at the early part of the autumn passage miss the early peak, and later counts suffer from the 'weekend effect'. Shore-based counters will have low numbers on land, thanks to the level of weekend shooting (Friday through Sunday), with many of these birds displaced to the island complexes, which are for the moment usually counted by boat earlier in the week.

Duck Soup

Sometimes when I'm out I get asked why I count. The answer is always the same. "I don't count for the number, I count to understand."

Rainham Creek

Why count wildfowl and waders?

Most birders think there's enough counting being done already, that they needn't bother. For an estuary, they often hold faith in WeBS. That sets out to meet three main objectives:

     (i) to assess the size of non-breeding waterbird populations in the UK
     (ii) to assess trends in their numbers and distribution in the UK
     and (iii) to assess the importance of individual UK sites for waterbirds

Even though we are heading out of the EU, many conservationists hope much of existing European Law will be kept in some form, leaving us with something similar to the existing EU Birds Directive and Habitats Directive which require us to identify important wetlands for birds and designate them as protected. It comes with compulsory monitoring to covering breeding, wintering, and migratory populations using the wetland.

Regardless of Brexit, the UK is bound by other international agreements. Also over and above us is the Ramsar Convention on 'Wetlands of International Importance especially as Waterfowl Habitat'. We have also signed up to the Agreement on the Conservation of African-Eurasian Migratory Waterbirds (AEWA). Signatories must conserve migratory waterbirds along the entire length of the flyways. Sites of migratory waterbirds to be protected and managed appropriately. So, adequate monitoring is needed for several vital international agreements, and WeBS is suitable for these as well. It is a vital national count.

Although WeBS aims for complete co-ordinated coverage, gaps happen and adjustments have to be calculated via the magic of algorythms and the like. All well and good, but the Medway is an oddity. No other tidal estuary in the UK has such a series of islands as those found here. I'm no statistician, but... local knowledge and interpretation is vital for understanding bird counts here on the Medway.

To illustrate this I want to blog about dabbling duck.


Dabbling ducks- the Anas family

Funton Reach

While counting, there are three main 'needs' to consider from the outset- breeding, feeding and safe roosting. The first we can forget for much of the winter (many duck do pair up on wintering grounds to save time when they arrive at breeding sites), leaving feeding and safe roosting, both straightforward enough to monitor; counts help to understand how and why so many birds stay on the Medway.

In general, loafing requirements are not unique to each type of dabbling duck, but diet and feeding behaviour do have more significant differences between each of the Anas species.

They all use feeding zones and loafing zones, which together form their core areas. Wintering grounds have to have safe core areas. A non-tidal loafing zone on the landward side of the seawall might well allow some duck to remain undisturbed all day, but if members of that same species have to loaf on mudflats then they have to work around the rhythms of the estuary, either moving or riding out the covering tide (and wasting energy by trying not to go with the flow). These problems are usually outweighed by the safe roosting, and for some, the chance to continue to feed if needs be.

So they might have to move a short distance to a safer salting when the tide comes in. They might also have to move again on the higher tides, and the largest spring tides pose their own problems here.

Then throw in the weather- what do birds do when their chosen loafing waters are frozen? Or when rough waters last for several days?

If you think counting with these sorts of things in mind is O.T.T., well we Brits do get off lightly with simple counts. For example, we only get asked to do Low Tide Counts by the BTO every six years, and usually just asked for the numbers of birds. If you look at somewhere like Eire, their count instructions instruct volunteers to go the step further and record numbers as loafing or feeding.


The general mix on the Medway

Working west to east, at the estuary head Chatham has a level of urban development gives no room for landward roosting, so few dabbling duck chose to loaf near the head of the estuary. By Gillingham the mudflats are widening and duck can sit out on the flats some distance from the shore. The first islands are also nearby and a few wildfowl can now loaf in cover on Hoo, or Copperhouse. (The latter goes under on spring tides when the birds make for Nor/Friars.)

Teal in particular favour Copperhouse, which belongs to Kent Wildfowlers and is shot, mostly at the end of the working week, (why midweek counts are usually highest here). Other species tend to float out into South Yantlet Creek and jump the wall into Nor,

They will be joined there by Sharps Green Bay and Rainham Creek duck on the higher tides. Both these sites do have low-lying saltings where the birds may hole up, but if covered by a spring tide, or disturbed, then they will flight out to Nor/Friars. (Nor is an RSPB reserve, but the adjoining Friars is Kent Wildfowlers, and shot routinely). On the highest spring tides Nor and Friars all but disappear; the duck will try to ride out the waves, or flight east.

The Motney peninsula offers some safe loafing for those species that enjoy dense cover, at the point in the reed beds of Southern Water Sewage Plant and along the reedy neck of the peninsula. The more open waters there that attract most duck are within the Kent Wildfowlers conservation area, while the section owned by Medway Council has seen less management and has more scrub encroachment. To the east, Otterham Creek is too narrow to offer safe roosting where the footpath runs alongside, but at low tide duck can loaf on the northern half in relative peace. The private grazing marshes behind the eastern seawall provide both feeding and loafing opportunities, but are working areas, and shot routinely in season.

This land is on the Ham Green peninsula, a large and obvious natural divide to the southern shore of the estuary. Beyond Ham Green, the shoreline is relatively undeveloped, the estuary is at its widest, and the major island complex sits just offshore as an appealing refuge (when not being shot).

So, from the low water mark out in mid estuary most dabbling duck will ride the tide up to south of Burntwick island to float and flight into the Greenborough complex, where they will be joined by birds from closer to shore from around the eastern edge Ham Green peninsula and Twinney/Halstow Creeks. Some might chose the Barksore peninsula, but the islands are more natural and offer many safe area, despite the frequent wildfowling there.

When disturbed from the shore, Funton duck also mainly ignore the ploughed fields on Barksore, instead opting largely for the grassland of the Chetney peninsula.There the many dykes and flashes spread among grazed grassland are much more appealing. Much of Chetney is a game shoot, with most disturbance seen at the week's end and the weekend. The majority of duck disturbed from Chetney will flight towards the islands.

This offers one explanation why WeBS duck totals seem routinely low- land based counters go out on the correct weekend dates when their duck numbers are often low when compared to mid-week dates, being disturbed by more fowling. With the waterborne counters mainly out mid-week, duck numbers around the islands are often lower, as they can loaf in peace closer to their feeding zones.

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Over the next few days a series of six short blogposts will look at the individual ingredients that make up the dabbling Duck Soup. Hopefully something to taste for all- bon appetite mes amis!

Bloors loafers

The Medway Duck Soup recipe-

A paring of Wigeon

A grating of Gadwall

A sieve of Teal

A julienne of Mallard

A scoop of Pintail

A chinois of Shoveler

Halstow Creek

Flighting up times

The last couple of session out have seen me mainly musing on disturbance- specifically, fireworks disturbance.

The tide on New Year's Eve had been covering just approaching midnight, which could have meant a fair number of birds close to shore. The traditional British approach of letting off fireworks from any time up to six hours before the stroke of midnight had already put paid to that. A check the following night (with fireworks still being let off around Gillingham), notched up fewer than expected territorial waders close in, and no sign of any moving flocks. Daytime checks along the urban stretches showed the species that follow the tide in, weren't. Just a few hundred Dunlin. It takes time for these birds to feel the area to be 'safe' again. Wildfowl have also been shaken up a bit; more urban stretches of estuary have seen drops in numbers of the 'loafing' daytime species- some 'feeders' (such as the mud-sifting Shoveler) are nearer normal count numbers. This, to me, is a main driver. Food. Go hungry competing for resources on the estuary, or risk starting to return to an area that had seemed totally alien just a night or so prior. If you have a safe secondary loafing/roosting site, you might stick with that for a while longer.

So numbers should rebuild slowly over the next few days, but how much effect does this disturbance have on the birds at the time? Details on a radar study just over the Channel showing just how many birds are caught up in such things can be found here. Dangers during the panic flights, competing for food resources elsewhere, cautious returns over a few days to territories, all add up.

Of course, it isn't just the estuary birds- as I described last year, other roosting species take fright and flight. One example- a typical December 31st  morning watching local flightlines will see a movement of Woodpigeons from safe urban roosts out into the countryside during the first 90 minutes or so, with a minimal commute in the opposite direction. After that time small numbers start drifting back in. A typical January 1st? Exact opposite. The flight back in, I'm beginning to suspect, might not be the commuters checking the roost site is still there, but more likely the urban Woodpigeon who feed primarily in Medway gardens, returning to their favoured feeding areas.

This would all be well and good if nocturnal mass flights did suffer fatalities (they do) and if having to desert favoured feeding areas didn't put strain on survival (it does, especially in hard weather).

Many birders only notice this through rares- "I hope X hangs on into the New year" (Birders of a certain age, hoping for a revisit for a millennium tick, will remember that Aldeburgh Ivory Gull, last seen December 31st 1999).

If you haven't bothered with the Dutch radar study linked above, I'll draw your attention to one thing- fireworks can only be sold to private consumers 29th-31st December. They can only be used for recreational purposes between 18:00 New Year's Eve and 02:00 New Year's Day. How different to the British approach of starting letting off fireworks days before and continuing well into the New Year (there were more last night here). The recovery period for their wildlife is thankfully short. We just keep banging on and on.

Better get back out and see if 'my' local flocks are back to their 2016 numbers yet.