Page 68 - BBC Wildlife Volume 36 #04

ytham Woods must bethe most studied
woodland in the world. “Harvard would
argue with that, but we’re definitely in the
top three,” laughs Nigel Fisher, conservator
of Wytham Woods since 2000. “In any
W case, it’s the long-term datasets where we
stand out–these records just don’t exist anywhere else.”
It’s hard not to feel a little awed by these, as he reels off a
list of continuous long-term studies on small mammals
(officially since 1962, potentially earlier).
But it’s the great andblue tit research that tops the
Clockwise from their health; Prof
list. Since 1947 more than 100,000 great tits have been above: Wytham Yadvinder Malhi
individually marked here. Dozens of generations of tits have Woods tit worksona
been followed – the longest continual stretch over which a fieldwork starts in canopy walkway;
single great tit lineage has been tracked is an amazing 38 spring; tit chicks ecologist
held by researcher Antica Culina
generations. More is known about this population of tits
Ella Cole to check sexes a great tit.
than any other bird population on theplanet.
Wytham Woods were bequeathed to the University of
Oxford by Raymond and Hope ffennell in memory of their
daughter, under the condition that the place would be used
for education, research and recreation. It was 1942, and
the timing was good: the study of animal ecology was in
full swing at Oxford and the Edward Grey Institute of Field
Ornithology (EGI) had just been established.

NEW HOMES
In1945, David Lack moved from a teaching position at
Dartington School to become director of the EGI. He had
just published his superb monograph The Life of the Robin
and was keen to set up a population study of the species.
Instead, inspired by a Dutch study, Lack switched to great
tits, which are natural hole nesters but will readily use BY TRAINING CERTAIN GREAT TITS TO SOLVE
nestboxes. Two hundred nestboxes were erected in 1947,
marking the birth of the Wytham tit study. PUZZLES IN DIFFERENT WAYS, IT’S POSSIBLE
Massive expansion came in the late 1950s after Chris
Perrins, now emeritus Prof of zoology, joined the EGI as TO TRACK HOW THEIR BEHAVIOUR SPREADS.
a research assistant and starting erecting hundreds more
boxes. By 1963, he’d increased the number to about 1,000. never forget the first time I held a wild great tit. It was
Ben Sheldon, who took over from Chris as EGI director in so exhilarating… yes, I was a bit scared I might crush it,
2004, added 200 more boxes for blue tits (which have a but the birds’ robustness and ability to withstand being
26mm diameter hole, as opposed to about 32mm for great trapped and handled is one of the reasons we use tits
tits). So today’s fieldwork team has the unenviable task of in ourresearch.”
checking 1,207 boxes every breeding season. Great tits have been given numbered metalleg rings
Blue tits became
thefocusof since the study began, but today each bird is also fitted
BREEDING SEASON research at with aplastic ring containing a RFID tag(similar to the
until
microchips attached to cats and dogs) These tiny tags
Fieldwork starts in early April and continues until midmid- W y tham in 194 7 microchips attached to cats and dogs) . The s
pril
and
continues
Wytham in 1947
June, when all the chicks have fledged. It’s pretty intense, whenDavidLack’s contain identity codes about each individua al,and can be
h
student John Gibb
as EllaCole, senior researcher and research coordinator read remotely, meaning fewer birds need to
h
o be caught to be
started erecting
h
explains. “A typical day at the peak of the field season identified. In a good year, when there is ple nty of food and
nestboxes.
r
can start before dawn, so around 5am, and finish high chick survival, each fieldworker may e nd up tagging
at 5–6pm. We have to work out which birds are upwards of 500 chicks: a phenomenal task. .
k
w
breeding in each nestbox, which generally
a
means catching the birds and reading their SURROUNDED BY SPRING
leg rings. Given that each oof us might be in It all sounds a bit exhausting, and I wonder r how hard it
d. “It’s pretty
charge of 150 nests, that is a lot of parent is to remain motivated for the whole period
birds to catch!” wonderful watching spring happening all a round you,”
In addition to recording various types says Ella, “and we get to see so much of the e woodland
have – in some
s
of data, all of the chicks must also be wildlife. While going about my work I h
hares, tawny owl
weighed and tagged. It’s beena few years cases literally –bumped into courting h
e
since I handled small passerines, but I chicks, deer, foxes and badger cubs. Not t bad foraday
e
well remember the initial panic about in the office.” The flipside is when it r ains, as the work
p
g
how tight to hold a tiny,15g bundle of still needsto be done.
nd day after day
feathers. Ella agrees. “I’ll “Sometimes you could spen
68 BBC Wildlife April 2018