Community

A tale of two waterbirds

Gadwall

Moorhen

Counters

 

Counting waterbirds on a monthly basis can be a bit of a slog at times. For a start, it takes several hours to get around all the lakes in Wanstead Park, let alone those on Wanstead Flats. The weather may be cold and wet, the paths muddy and sometimes not very much has changed since the previous month. Counting gulls on Wanstead Flats is particularly frustrating, regularly producing the classic situation where – close to the end of logging a large loafing roost of Common Gulls, 583, 584, 585 … a dog charges through the middle and disperses the lot. Right, where was I? 1, 2, 3, 4 …

Despite this, the numbers produced provide useful information for the British Trust for Ornithology (BTO), helping them to evaluate which species are faring well and which are in trouble. Locally, we have a team of tireless counters, so during the winter months not only Wanstead Park and Wanstead Flats but Eagle Pond (Snaresbrook) and Hollow Pond (Whipps Cross) are covered. We also now have an almost complete record for the months of autumn, winter and early spring stretching back to January 2009. That makes it possible to look at trends and, maybe, draw some conclusions. Combined counts for Wanstead Park, Wanstead Flats and Eagle Pond can be compared now over seven WeBS counts. Systematic counting has only recently restarted at Hollow Pond, so a comparison cannot be made including that site. Browsing through the figures, trends for two birds jumped out at me: those for Gadwall and for Moorhen. Figures for the recent WeBS count produced record January numbers for both species.

The ‘Gadwall army’

The main concentration of Gadwall in our area is on Alexandra Lake and the lakes of Wanstead Park, all waters where there is plentiful weed for these ducks to eat. Numbers at Eagle Pond rarely exceed single figures. The rate of increase was slow and irregular in the first years of the sequence: 40 in January 2009, 24 in January 2010, 101 in January 2011 and 88 in January 2012. During these years, the peak counts were respectively 111, 86, 137 – and this is where things really start to lift off – 200+ in December 2012. Since then, the rise of the ‘Gadwall army’ (as former Wren newsletter editor Steve Swaby has dubbed it) has been seemingly inexorable, with 363 in December 2013 and 459 in December 2014. The 422 counted in January 2015 was the highest-ever January count, and the biggest count on a WeBS day.

Gadwall was a pretty rare bird in London not that long ago. According to Andrew Self (The Birds of London, 2014), the average wintering population in London was only about 100 in 1970. Wanstead Bird Reports from the late 70s and early 80s mark it out as a local rarity. However, by the end of the century the London winter population was around 2,500, and Self describes an average of 600 in the Lea Valley in recent years. The peak count (at the time of publication of his book) he lists was 453 at Cheshunt GP in December 1989. A larger share of London’s birds is now wintering in Wanstead, but there is no obvious reason why. Clearly there is a plentiful supply of weed on which the birds can feed, and maybe the growth of weed in our lakes has made it easier for these attractive dabbling ducks to feed by upending. Whether other factors are involved – such as an increase in the continental populations from where most of our birds originate, or problems with the food supply at locations where they previously wintered – is not clear. One thing is certain, we should enjoy the phenomenon while it lasts because like pretty much everything in nature, numbers go down as well as up. Cutting of the weed in The Basin later this year may well impact on the numbers that lake can support next winter.

Moorhen success

Another success story, though much less dramatic, concerns Moorhens. Again, January WeBS figures for the years 2009-2015 show a consistent increase: 20, 21, 35, 44, 2013 figure lost by a careless recorder!, 66 and 80. And maximum counts for those years were as follows: 47, 56, 35, 65, figure unavailable, and 78 in 2014. Judging by the number of juvenile Moorhens seen on our lakes in recent autumns, I believe this increase can be put down to local breeding success. The species nests in emergent vegetation, where they are better protected than Coots’ nests, which are exposed stick islands, easy pickings for Lesser Black-backed Gulls. With the highest-ever January WeBS count for the species this year, I reckon we could be in for another bumper breeding season.

Tim Harris 19/1/2015

1 Comment »

Rainham Marshes visit 11 January 2015

WREN Awayday Rainham Marshes
One of the most evocative sights of a chilly winter’s day is that of hundreds of Lapwings climbing into a bright blue sky, their underwings glinting brightly in the sun as they turn. This was something we witnessed several times on the Wren Group awayday to Rainham Marshes RSPB reserve on Sunday 11 January. The morning began with a beautiful Redwing perched up nicely near the visitor centre and the afternoon ended watching a roost of 25 Redshank on one of the stone barges near the Tilda Rice Factory (a lyric from a Morrissey song?). I love the juxtaposition of industrial and green landscapes, and this stretch of the Thames, with the former grazing marshes of Rainham and Aveley on one bank and the smoking stacks of Belvedere and Erith on the south shore have this mix in bucketloads.

It was a day for watching ducks in their most brilliant plumages: Wigeon, Teal, Pintail, Shoveler and Mallard. A day for walking the boardwalks with the occasional rather subdued burst of Cetti’s Warbler song as accompaniment. And a day for looking in vain for Bearded Tit and Water Rail … Respite from the bitter wind came in the large new hide at the west end of the reserve, where two Stonechats performed well for the group. Before some of the group broke ranks and walked along the Thames path in search of pipits, a female Marsh Harrier rose to quarter the marsh to the west and a Kestrel passed overhead. The Thameside walk produced scant rewards – very poor views of one Rock Pipit – but it was a pleasant-enough diversion. Then it was back to the visitor centre for hot drinks before a final stop at the stone barges. The combined ‘day-list’ was 56 species, but it’s not about numbers; it’s about sharing time with like-minded people and enjoying nature in the heart of an industrial landscape.

Thanks to Dave, David, Don, Eleanor, Gill, Hannah, Kathy, Linda, Nayna, Peter, Rosie for making the day so enjoyable.

Tim Harris 11/1/2015

Mute Swan, Canada Goose, Shelduck, Wigeon, Gadwall, Common Teal, Mallard, Pintail, Shoveler, Pochard, Tufted Duck, Pheasant, Little Grebe, Cormorant, Little Egret, Grey Heron, Marsh Harrier, Kestrel, Moorhen, Coot, European Golden Plover, Lapwing, Dunlin, Common Snipe, Redshank, Black-headed Gull, Common Gull, Lesser Black-backed Gull, Herring Gull, Great Black-backed Gull, Feral Rock Dove, Woodpigeon, Collared Dove, Skylark, Meadow Pipit, Rock Pipit, Pied Wagtail, Dunnock, Robin, European Stonechat, Blackbird, Fieldfare, Redwing, Mistle Thrush, Cetti’s Warbler, Blue Tit, Great Tit, Magpie, Carrion Crow, Starling, House Sparrow, Chaffinch, Greenfinch, Goldfinch, Linnet, Reed Bunting.

Leave a response »

Rare grebe drops in

Slavonian Grebe - KHOn Saturday 3rd January Nick Croft found a winter-plumaged Slavonian Grebe on Heronry Lake, in Wanstead Park. The bird – which is intermediate in size between Little Grebe and Great Crested Grebe – is still present at the time of writing. It has been diving almost constantly for small fish with, it has to be said, a great deal of success. This bird represents the first record for the ‘local patch’ of Wanstead Park and Wanstead Flats and has helped local patch-listers get the year off to a great start. In a national and European context, Slavonian Grebe is a scarce species. The British Trust for Ornithology puts its UK population at around 30 breeding pairs, while the estimate for Europe is between 4,800 and 8,000 breeding pairs. In the period 2004/5 to 2008/9 the population wintering around British coasts averaged just 1,100. A few birds are known to spend the winter months off the coasts of Essex and Kent and it is likely that this bird was displaced from coastal waters by the stormy conditions between Christmas and New Year. Will it stay? Probably not, but if it does we’re in for a real treat because the breeding plumage is spectacular and gives the birds its North American name, Horned Grebe.

Other interesting sightings in the first few days of the year include a probable Woodlark with the Skylark flock on the western part of Wanstead Flats and a Lesser Spotted Woodpecker in St Mary’s churchyard, Overton Drive.

Tim Harris, 7/1/2015

Slavonian Grebe pic: Kathy Hartnett

Leave a response »
« Page 1, 2 »
http://www.health-canada-pharmacy.com/add-and-adhd.html | http://www.cheapambienpriceonline.com | http://www.besttramadolonlinestore.com