Thursday 31 January 2013

points/per/bird

There are 2 ways of accruing a high score - seeing a lot of birds, or finding high scoring birds, like the Gyrfalcon that recently graced an Askernish rooftop! (Don't forget, scarce birds worth three points are doubled if you find them, and rare birds worth 4 and 5 points are trebled if you are lucky enough to stumble across them).

One way of assessing the quality of a year list is to look at the points scored per bird (which is very simple to work out - simply divide the number of points by the number of species). My points per bird for the last two years are as follows:

2011 - 1.297

2012 - 1.380

Living by the coast, I'm lucky enough to get several easy 2 pointers every year, like kittiwakes, razorbill and the like. These are my bread and butter. The ones that really make a difference to the points per bird are the ones for which you get the finds bonuses (see above). 2012 was a much better year than 2011 for finds bonuses, with three 'finds' scoring me an extra 9 points. If someone else had found these birds my points per year would have been 1.313. If I hadn't seen them at all, it would have been a lowly  1.274.

You'd think that the best time to see these 'extra pointers' might be the spring and autumn - and if your patch was on the east coast like mine you'd probably be right. The graph below for 2012 shows a big peak in October (when I picked up YBW and barred, and saw a lovely but unfortunately second hand RBfly), but shows no real peak for my other 6 pointer (an April wryneck - probably as it would have been somewhat 'swamped' by the scoring of lots of 1 point birds in the form of common migrants). The blue line is the monthly 'ppb' with the red line representing the year end 'ppb'.


The points per bird graph for 2011 looks somewhat different though - a trough in October and peaks in August, and perhaps a little more surprising, March. Just goes to show that it's worth getting out there at all times of year - you might find yourself scoring very valuable points at a time when you least expect it!


And thats enough of the graphs for now...

4 comments:

  1. Can never be enough graphs ;)

    I guess I feel pretty good about my 1.3 ppb last year now. I had expected it to be lower

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  2. A truly inspirational pair of graphs, Mark! :o)

    I like graphs. Really.

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  3. I like graphs too.

    The way they go up, and down - but not always at the same time.

    And sometimes they go across.

    And if you alter the values on the side and on the bottom, the up and down gets steeper or less steeper as the case may be.

    But, sadly, the across bit always stays the same - whatever you do .

    . .

    Rumours of a Moorhen on The Patch - early night for me.

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  4. Inland, nowhere near a major waterbody, 3 pointers are the stuff of dreams (I've had one in 3.5 years: Crane, which doubled up to 6 on self-found rules). Frustratingly, a patch first and Breckland mega like Common Scoter scores just 1 point (cf 2 for Little Egret, a species I see on a third of my patch visits these days). And Thetford's Black-bellied Dipper (a BBRC subspecies)? Yes you guessed it: 1 point.

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