Page 69 - BBC Wildlife Volume 36 #04

TIT RESEARCH
sloshing around in the rain, trying to catch birds
and keep everything dry, and thinking ‘I just
want to go home!’,” admits Andy Gosler, a
lecturer in ornithology and conservation who
conducted fieldwork on Wytham tits for 30
years. What’s more, the birds didn’t always
makeiteasy. “Certain experiencedbirds got
to know me and became extremely difficult
to trap,” Andy says. “There was a little battle
of wills because I had to redesignmy traps to
make themmoreeffective.”
Great tits can be rapidlearners and are
known to innovate novel feeding solutions, and
while they are often thought of as the dominant
birds around a feeder, individuals differ quite a lot
in their personalities. When great tits are temporarily
taken from the field and placed in a new environment
some birds immediately explore every part of it, whereas
The birds, here
others stay rooted to the spot. The bolder explorers also a male great tit, A current focus is on social behaviour, for example, and
tend to be more aggressive and more likely to take risks are fitted with
than their ‘shy’ counterparts. tags as part of By training certain individuals how to solve simple box-
the study.
How these differences relate to their survival and
breeding success is intriguing: bold birds tend to takea
‘live-fast die-young’ approach, prioritising their current
broods over their own survival,whereas shy birds are
more likelytoabandon nests that are threatened and
prioritise survival. There are other differences, too. Shy
males avoid nesting near bold males, possibly to avoid
confrontation with the more aggressive individuals. Bold
males are more likelytocheat on their partner. However
they suffer a cost for their dalliances, as their partners are Rome, do as the Romans do’,” says Ben. “They are being
more likely to cheat on them, too.
April 2018
HOW DO YOU
WEIGH A SMALL BIRD?
For decades, tits and other small passerines were weighed
using spring scales. Birdswereplaced inaclothbag, which
was loosely tied at the top, then suspended from the scale.
Today,Wytham fieldworkers carry small electronic scales
that give a more precise digital output.“The best way
to keep the birdsstill on thescales is to pop them, head
down, in an old 35mm film canister,”says Ella Cole.“This
doesn’t look very dignified, but it minimises distress
for the birds as it limits their vision. It calms them in
a similar way to putting a hood on a bird of prey.” When
chicks hatch, they weigh close to 1g. In just two weeks,
thanks to industrious parents provisioning around 1,000
caterpillars per chick, the young are ready to fledge and
often weigh more than their parents.
Ella Cole
weighs a great
tit in a film
cannister.
The personality research
represents one of the huge
research shiftssince Lack’s
time. Back then, much was still
unknown aboutfundamental
great tit biology, such as how long
the birds lived, how many eggs
they laid or how far they moved. All
that data is still being collected, but
the beauty of the Wytham tit research
is that this robustfoundation of data
has made possible finer-grained studies of
behaviour, genetics and ecology.
PASSING ON INFORMATION
how social interactions influence the spread of information.
opening puzzles in different ways, and then releasing
them and the puzzles into the woods, it was possible to
track how the behaviour spread. Birds readily learned from
others: those that associated with knowledgeable birds were
considerably more likely to pick up the technique.
Surprisingly for the team, tits were influenced by the
specific technique most prevalent in their population,
even though it had no advantage over the other in terms
of accessing the food. “It’s the bird equivalent of ‘when in
conformists in the way that they learn.”
BBC Wildlife 69