How to bird the Medway

The Medway is, to many visitors, a hit and miss affair, with birds often too distant to appreciate. At 44 square kilometres and without a shoreline public reserve, it can appear to be too big of an area to bird easily. But there are some tricks that will help you get the best from the shoreline.

1) Estuary charts

Maritime charts are an absolute must. A chart covering the North Kent coast is useful for the more general birder, but for anyone concentrating on the estuary, more detailed charts are available. An ordinary map may name one or two creeks, but a Maritime chart names the lot.

2017: edit - good news: worldwide marine charts are now available online (but remember to use the dropdown menu and change the depth in feet to metres! This then matches most tide tables.)

For the sake of counts, it is worth considering mimicking the national surveys. That way, if you are in the habit of reporting your counts via BirdTrack, etc., the data can be much more easily analysed/compared. The BTO Low Tide Counts (LTCs) are perhaps the better to use when making inter-tidal counts and is available here via the drop-down menu. (the interactive species maps are well worth a browse). BTO WeBS itself has detailed maps for the estuary and each count area (c/o 'find a vacant space' interactive map here) and make useful boundaries for covered/high water counts (the intention is for a detailed description of these sites to be provided on the blog at a later date).

2) Working the tide for waders

Most birders visit the Medway to watch the waders. From August through to the start of March, there are always good numbers and variety of species on the estuary, and high tide is a great time to see distant flocks wheeling over the islands.

But for the closest views of waders, working a rising tide is nearly always best. Falling can be good, especially in late winter when birds have no choice but to make the most of daylight feeding, but in late summer and autumn falling tides will always have fewer birds closer to shore on the fall.

Some species follow the tide line, others do not. At low tide many have worked their way right out to centre of the estuary. At this time the Medway can look devoid, with a few Oystercatcher and Curlew scattered around, a few handfuls of Redshank loafing in the creeks. The birds work back with the tide. If they have fed enough, some can 'short-stop' and roost some distance out on the flats before heading directly to roost but, the hungrier they are, the nearer to shore they come.

Most tidal forecast websites only give high and low water. To increase your chances of connecting with the biggest numbers of birds, you need to know what time the mud begins to cover. Of course, nothing is uniform in  an estuary and through a normal year the mudflats deplete/accrete. So it is never an exact science, but during the past three years I have worked out the 'typical' heights for when each area starts to flood. The creeks feeding the area should be just nearing full, and there will be time to enjoy the birds being pushed up towards you.

I find the BBC tidal forecast site invaluable. There are forecasts available for several sites around the estuary, but I settled on the central Bee Ness jetty as my marker. From the screengrab below you can see how the tidal flow is shown in full. By running your mouse over the chart, you will obtain a forecast height by each ten minute period.

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The key time for much of the estuary is for the 3.0 metre mark. Some of the central channels and their adjacent flats have already gone under, but 3.0 metres is a good guide. Key heights for specific areas are listed below, and should allow you to settle in to watch the rise for around at least 30-45 minutes.

- St Mary's Island- arrive pre 3.0 metre
Small flats, no large roosts nearby.

- The Strand (Gillingham Marshes/Cinque Port Marshes)- arrive pre 3.0 metre
Many birds move east to Copperhouse Marshes for final feeding.

- Riverside Country Park (Copperhouse Marshes/Sharps Green Bay)- arrive 3.0 metre
One of last areas to go under, many birds will be out feeding mid estuary to about this height. can move from flats both to the east and west for final feeding.

- RCP (Rainham Saltings and Rainham Creek) arrive 3.0 metre 
Many birds will often make last fuelling here before returning north to Bishop/Friars/Nor to roost, or in the Saltings on neap tides.

- RCP (Bartlett Creek)- to watch the distant flocks on the central mudflats, arrive pre- 2.5 metres. Bartlett Creek has covered a great deal of the mud north of Motney by the 3.0 metre mark.

- Otterham Creek head- pre- 4.0 metres.
The head of this creek is one of the final areas of the southern Medway to flood on a covering tide. (Note that the central third floods by 3.0 metres.)

- Shoregate Creek, Ham Green (for the Ham Ooze complex)- pre- 2.0 metres.
The various outer flats here are pretty much covered by the 2.5 metre mark.

- Shoregate Creek, Ham Green (south to Millfordhope Creek and Saltings)- by 2.5 metres
One of the quieter stretches, never large numbers unless feeding hasn't been good elsewhere on the rise. Saltings not fully under until c. 3.4 metres.

- Lower Halstow (for Twinney Creek and Halstow Creek)- arrive pre- 2.6 metres
Halstow Creek floods first, Twinney covering around the 3.2 meter mark.

- Funton (Funton Creek, Funton Reach, Bedlams Bottom)- arrive 3.0 metres
The Reach is first to flood, and although near shore does not go under until about the 4.0 metre mark, most birds will be off to roost after around the 3.5 metre.

- Queenborough (Queenborough Spit) arrive pre- 2.0 metres
The tide runs quickly here, and most is covered by the 2.5 metre mark. Movements in from the Thames can be impressive, so can be worth hanging on until about the 4.5 metre mark.

- Sheerness (Jacobs Bank) arrive pre- 0.5 metres
- Sheerness (Bartons Point) arrive pre- 0.5 metres
Both are outside the estuary but are watchpoints for the Medway deep water channel. Feeding waders and geese along this stretch will often flight west to roost in the Medway estuary.

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The next thing to consider is the tidal height. When sun and moon align, the tidal effect is greatest and you have 'low' low tides and 'high' high tides over the course of four or five days- the latter are known as spring tides. On springs, mudflats cover/uncover in shorter periods, tides race, and bird behaviour also changes- feeding areas usually unavailable on the normal tidal range uncover for a short while and may attract birds away from their 'normal' haunts. At the other end of the scale, several usually occupied roost sites will be flooded out- for the Medway generally, any tide 6.0 metres or higher will flood some roosts.

There are also neap tides, when the sun and moon play against each other and the tidal range is smallest. It sometimes feels like the tide has failed to go out. Not only has the water failed to drop, but the flats have retained a lot of water and birds have less need to follow what ebb/flow there is. Any tide, say, 5.2 metres or below will see waders not bothering to move about so much.

For working out tide times precisely, it really is also worth checking surges. Extreme air pressures on water mess up tidal predictions, and there are a lot of low pressure systems during the course of a normal winter. Lows allow the tide to run quicker, and this winter has seen surges of up to 1.8 metres- turning up at the predicted forecast time on one of those days and you find the mud has already gone.

Negative surges work in reverse- you can be twiddling your thumbs waiting for water. And, to really muck things about, surges don'e always run smoothly; there can be a metre difference on the covering time but normal by high tide itself.

For me, the website of greatest help in avoiding such errors is c/o National Tide and Sea Level Facility and a screengrab of today's forecast the tides are running 30 or so minutes late, thanks to higher pressure keeping the waters down.

This may all seem a lot of work, but it means I never now miss a covering tide, which helps a lot when on foot/bike as much as I can be(!) Hope of some use for yourselves.

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The only other thing I'll mention is daylight differences. Yes, waders can and do feed at night. But for many species, feeding rates change. Those which rely on sight may switch more to probing. Some may change sites for better/less lit areas. General rule of thumb, intake rates never as good. And some roosts aren't as safe at night, so change other sites (onshore island roosts on pools often have their highest numbers at night).

All this means a covering tide first light can be way different to one covering in the afternoon. Only an hour of feeding first thing? Birds are going to be feeding hard. Afternoon covering? Some might not venture close to shore but head straight to roost.

Similarly, an uncovering at dawn can see a lot more activity than one dropping later in the day; if birds have had a good morning's feed, they will leave their afternoon roost that little more leisurely.

Hour after uncovering, not only will many have then followed the tide out, but many will already be needing to rest up in the tideways and digest their breakfasts. Things go quiet fast.


3) Wildfowl

Similar, but different. An awful lot of feeding, right up to mid-/ late- winter, takes place out on the mudflats. And a lot of it is at night. But day roosting close to shore, away from the shooters, is a given. So, the covering tide time actually give you the highest numbers; many duck will be hidden up until all the tideways and creeks flood.

Again, highest numbers are early on; many birds day roost away from the public areas (e.g. many Teal retreat to the reedbeds, other dabblers switch to larger fleets to bathe/rest).

Biggest difference is mid-/ late- winter onwards as saltings and onshore field start to regrow; birds switch to the fields in growing numbers, and, where undisturbed, rest up more on landward side of seawalls.

4) Visible migration

This term relates to those birds that, in the main, do not migrate by night. Mostly late autumn passerine species, hirundines, and tide initiated wildfowl/waders.

One of the biggest clues comes c/o BirdTAM; although designed for pilots (so forecasting movement at heights, the trends are generally good for helping birders yet to get to grips with the nuances of individual species. And also worry too much about learning to read weather charts. The example shows a forecast of viz mig fireworks on November 5th after a few days' break. Low country movements often involve birds that make their way over the Channel and through Kent. Much better to use this for trends than look at what's been happening in northern England.

For inspiration, checking individual site results along the Low Countries and French coastlines, you can do no better than Trektellen. You can also check by species map, by day totals or birds per hour.

6) Songs and calls

The final site I always find myself mentioning in the field is Xeno Canto. Not just (worldwide) bird song records, but calls- flight, alarm, nocturnal. A wonderful resource.