This is a post for those who like a nice stat - I can think of at least two friends who might fall into that category, based on their love of a juicy morsel of e-bird data (Jono) and a perfectly formed spreadsheet (Bradders). Basically it's a few charts I pulled together based on a big year of birding mainly by bike in 2021. I'm partial to a bit of data myself - I put it down to a mis-spent youth as an amateur psephologist whilst studying politics at Uni - and while my charts are not exactly works of art, I think they tell the story of the year in a different way. And perhaps one a bit more accessible to those who couldn't face my 'review of year', which was somewhat longer than a Fidel Castro speech to the faithful.
My friend Jol keeps telling me to write a book about my 2021 non-motorised year list, but in the highly likely event that this doesn't happen (or that even if it does that it'll never make it into print), rather than saving the charts for that I thought I probably ought to lodge them here so at least the effort which went into totting up the numbers isn't totally wasted. And with 2021 rapidly becoming old news in the fast-moving world of social media it's in danger of becoming a bit ripe anyway.
Anyway, to the charts, and first up (above) is the number of species seen broken down by month. This pattern will be familiar to many a keen year-lister, with the usual binge in January followed by a bit of a dry spell before spring migration kicks in, succeeded by the summer doldrums. I haven't year listed for ages so I'm not sure what the last third of the year would normally look like, though I suspect my profile for that period isn't typical. I had certainly expected to pick up more than 2 new species in September, though in truth Dorset was pretty dire for early autumn migration. The real surprise though was the acceleration through to December, my fifth most productive month after Jan-April inclusive. That said I guess 'effort expended' and 'time off work' played a part as commitment/desperation drove me over the border into Hampshire for a 3-tick day during the Christmas holiday.
Next up, the sweat-ometer: my mileage cycled by month during 2021 (above). You can see how the year list was a bit of a slow burn thing, and that I didn't super-commit until spring migration kicked in. That said, this only shows miles cycled not walked, and there were a fair few of the latter in January and February as I swept up all available species wintering on the patch at Swineham (more on which later). Perhaps surprisingly, given how much it felt like I was hammering it on the bike from about April onwards, only three months (April, May and July) saw me break the 300 mile barrier (which I've already done in January 2022). Then again, in the winter months when my cycling tends to be more restricted to daylight at weekends, 200-300 miles a month still works out at about 50-75 every weekend so not bad going.
The maths geniuses among you might have worked out chart 3 (above) already as it's basically a function of chart 2 divided by chart 1. And although not surprisingly the early months of the year offered the best effort:reward ratio, it kind of illustrates how hard I had to work to add to the year-list in the later months - and particularly September!
Next up, the epics: my top 25 twitches by bike in 2021 (above) - just the one over 80 miles (the only time I crossed the border into Devon) and also only one over 70 (the last of four trips over the border in the other direction to Hampshire). Interesting (to me at least) that there were almost twice as many trips over 50 miles as over 40, though that probably reflects the lure of Portland, a 56 mile round trip without detours, to which I cycled 6 times over the course of the year. Only a couple of dips made the top 25 - Black Tern at Blashford Lakes being the biggest - with the other one (Glaucous Gull) being seen eventually at the third attempt. There were a lot of 30+ mile trips that didn't quite make the top 25, and if I go a weekend these days without a journey of that length I almost consider myself to be slacking!
And my final chart, of more local interest, and even then I'm not sure how much interest (!), a breakdown of the sites where additions to the year list were acquired. I'm not sure this tells you much really, other than 'where I went' in 2021. But I include it if only to prove to doubting friends that I did actually visit my local patch at Swineham over the course of the year. A typical visit produces c.45-50 species so I must have gone at least twice ;-). I guess it does also illustrate the importance of the Studland peninsular to a good year list in these parts, blessed as it is with a range of habitats to attract waders, seabirds, heathland and woodland birds, not to mention the odd exotic pheasant or parrot!
A few final stats then: for the hard-core 'green' birders, the number of species seen by non-motorised means in a year expressed as a percentage of ALL species seen is one of the ultimate tests of list purity. Over 90% is pretty pure. I didn't quite manage that, as the carbon-halo slipped on a very productive trip with Team Shetland which added a whopping 27 species to the 'all modes' year list, reducing my score to 86.15%. If I discount Shetland (which I know is a bit like the Government not counting aviation to calculate the UK's carbon footprint), it comes out as a more respectable 95.73%. But my Dorset ratio is probably the most flattering: of 223 species seen in the county in 2021, 220, or 98.65%, were seen on foot or by bike. Only Ring Ouzel, Chough and Desert Wheatear were seen travelling only by car, and it would have been dark had I attempted to see the last two by bike!
Anyway, I hope you enjoyed the charts as much as I enjoyed fumbling with Excel. I'll try to make them even prettier next year!
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