‘Delicious autumn!’ said George Eliot and with the leaves
now turning to golds and reds after a blazing summer, we probably all agree
with her.
But winter brings its own rewards and we are all now on the
lookout for the arrival of winter thrushes on our College estate. For the past
seven years the Writtle Conservation staff and students have been doing their
own little bit of ‘citizen science’ by monitoring the first occurrence of
various seasonal indicators, such as the first Red-tailed Bumblebee and first
House Martin of spring.
So, looking back, did spring arrive early or late this
year? Well, quite late actually! This graph shows when the House Martins have
arrived at Writtle College over the last few years. The number of the left hand
axis is the so-called Julian Day i.e. the higher the number, the later the
birds arrived. So we can see that for the past two years, our House Martins
have delayed their arrival, perhaps due to colder conditions hanging on longer
into the year.
In autumn however, we look to the north for the first
Redwings and Fieldfares. These birds will be arriving any day now and if you
see any on the Writtle College estate, please join in our citizen science
experiment and tell us which one of the two species it was, how many you saw,
when and where.
Image source: Wikipedia
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