Sunday 11 December 2011

Stats for 2011

After a weekend primarily concerned with catching up on sleep, working through a Christmas party hangover, and drafting an economics essay, I’ve been feeling the need to engage in something vaguely bird-related this afternoon. So I’ve been updating my records, keeping track of the rarities and scarcities I’ve seen in 2011. Although the year’s not out yet, I reckon the chances of seeing much more are pretty slim, given our plans for Christmas, so I’ll get in ahead of the inevitable flurry of ‘review of the year’ posts…

2011 was another acceptable year for British lifers, with 11 new species finding their way onto my list, taking the total up to 426 (BOU). Things were surprisingly quiet through the spring, though White-throated Robin and Roller in the space of a week got things ticking along nicely. I was pleased to see two long-awaited ‘tart's ticks’ fall in midsummer, too (Cory’s and Western Bonelli’s). Unlike last year, Shetland didn’t hit the jackpot in September, but the Yankee double-act on Scilly were both stunning. The autumn has been remarkably protracted as well, and a couple of late bonuses got me into double figures:

Lesser White-fronted Goose 2-Jan-11 Buckenham
Rufous Turtle Dove 26-Feb-11 Chipping Norton
White-throated Robin 7-Jun-11 Hartlepool Headland
Roller 13-Jun-11 Hollesley Common
Western Bonelli's Warbler 4-Jul-11 Arnfield Reservoir
Cory's Shearwater 9-Jul-11 Porthgwarra
Black-and-white Warbler 17-Sep-11 Lower Moors
Sandhill Crane 4-Oct-11 Boyton Marshes
Northern Waterthrush 28-Oct-11 Lower Moors
Sharp-tailed Sandpiper 19-Nov-11 Chew Valley Lake
Western Sandpiper 2-Dec-11 Cley

11 ticks is pretty much par for the course – just below my average for the last nine years. What that actually reveals, though, is that I must be twitching more seriously and travelling further for new birds these days, since you’d naturally expect to see less and less each year as the game gets harder. Not sure how long that trend will continue – having twitched Scilly twice this autumn, I’m not sure there’s much further to go!

But extending the data sample beyond just lifers, there’s a few more insights to be gained. First, it reveals a few notable ‘multiples’ in 2011: 18 Yellow-browed Warblers (Shetland clearly still good for something!), 17 Sabine’s Gulls and 13 Grey Phalaropes (both boosted strongly by an excellent Pendeen seawatch). Then there were 4 Cattle Egrets, and 3 each of White-winged Black Tern and Woodchat Shrike. And my first Western Bonelli’s Warbler was followed by a second just a few weeks later… how often does that seem to happen?!

So where have I seen all these birds? Along with day-to-day records in an old-fashioned notebook, I keep track of all rarities and a range of other ‘notables’ in an Excel spreadsheet. (The list of species recorded is influenced a bit by my east coast background, so things like Balearic Shear and Storm Petrel are on there, alongside scarcities like Lapland Bunting and Yellow-browed Warbler). This makes it very easy to summarise where I’ve seen the decent birds. This year, the number of records per county looks as follows. (Note that The charts indicate ‘species days’ – so loads of Poms somewhere on a single date only counts as one).

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But I haven’t always birded from Shetland to Scilly each year – compare to the overall totals, since I started birding. (This includes only the counties where I’ve seen more than ten notable birds):

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No prizes for guessing which county I grew up in! I’m quite surprised that there’s such a gap between Norfolk and Suffolk (since as a kid, it seemed that we were down at Minsmere every other weekend)… but the spreadsheet never lies. It does illustrate how much you can see with a few trips to Scilly or Shetland, though – relatively few days birding there in the autumn really racks up some quantity. Continuing on a similar theme, the next chart looks at the best sites through my historic records:

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Check out Rainham! Better than Minsmere, Porthgwarra and Dungeness! Unsurprisingly this isn’t a particularly accurate stat – it’s simply boosted by multiple days with Caspian Gulls, Penduline Tits and Serins…

But Cley genuinely is head and shoulders ahead of everywhere else: the only significant multiple here is Temminck’s Stint (seen at least one here five times, including two triples). It’s clearly delivered plenty of real quality, as well, with no less than eight lifers over the years. Minsmere comes second with six, and Titchwell with five.

Finally, it’s interesting to break the records down month by month. The chart below shows lifers on one scale, and rarities and scarcities on the other. No surprises here – there’s a notable pick-up in spring, especially May, and a bigger one in autumn. (It’s also clear you should go on holiday in March!) In the autumn, you can see a slight difference in trend between lifers (which peak later, in October), and other ‘notebook padders’, peaking earlier in September.

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