Geoffrey,
Thank you very much for this. It was highly instructive. My own hesitant
initial estimate was 60-70 birds - serious undercounting, as it turns out.
In future, I wonder whether it might be helpful if, when counting
smaller numbers (20 or so) where counting of individuals is feasible,
one were to take a step back after the count, take a fresh look at the
group and say to oneself, "Right. That's what 20 birds looks like."
John Brannan
Geoffrey Dabb wrote:
Very interesting. Estimates mentioned to me ranged from a wary ‘0 –
not starlings’ to ‘200-300’. It might or might not be helpful if I
told you that each of the first 4 coloured sections represents 50 birds:
I would think that very few people would know, intuitively, what 200
birds ‘looks like’. Barbara P mentioned the semi-counting method of
counting 10 - then counting the number of tens. That depends on
having the flock in view for long enough. John Rawsthorne – an old
sheep-counter like a few others – said if it looks like 100 it’s
probably twice that number. That is, in a way, knowing what 200
‘looks like’ - it looks like 100. That kind of knowledge comes from
knowing at some stage the actual number of estimated quantities, so
perhaps the sheep counters have an advantage.
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