By Science
News Staff / Source
With
an increasing human population and expansion of urban settlements, wild animals
are often exposed to humans.
As
our species may be a threat, a neutral presence or a source of food, animals
will benefit from continuously assessing the potential risk they pose in order
to respond appropriately.
European
herring gulls are increasingly breeding and foraging in urban areas, and thus
have many opportunities to interact with humans.
Madeleine Goumas and her colleagues from the Centre for Ecology and Conservation at the University of Exeter recently found that these birds take longer to approach food when
being watched by a human.
However,
it is not known whether aversion to human gaze arises from experience with
humans, and whether individual differences in responsiveness are a result of
differential exposure.
In
the new study, the researchers tested whether herring gulls’ responses to human
gaze differ according to their age class and urbanization of their habitat.
“We
know from previous research that gulls are less likely to peck a bag of chips
if a human is watching — but in that experiment a researcher either looked at
the gulls or turned their head away.”
“In
our new study, the experimenter approached while facing the gull and only
changed the direction of their eyes — either looking down or at the gull.”
“We
were interested to find that gulls pay attention to human eye direction
specifically, and that this is true for juveniles as well as adults — so their
aversion to human gaze isn’t a result of months or years of negative
interactions with people.”
The
study was conducted in Cornwall, UK, targeting adult gulls (aged four years or
older, evidenced by white and grey plumage) and juveniles (born in the year of
the study, with completely brown plumage).
A
total of 155 gulls were included in the findings: 50 adults and 45 juveniles in
urban settlements, and 34 adults and 26 juveniles in rural settlements.
The
scientists approached gulls while either looking at the ground or directly at
the birds.
The
birds were slower to move away when not being watched — allowing a human to get
2 m (6.5 feet) closer on average.
Juveniles
were just as likely to react to human gaze direction as older birds, suggesting
they are born with this tendency or quickly learn it.
Gulls
in urban areas could be approached more closely than those in rural areas,
consistent with findings in other species.
As
well as being quicker to flee, rural gulls were also more than three times as
likely to fly — rather than walk — away from an approaching human, suggesting
they are less used to being approached.
“The
growing number of herring gulls in urban areas may make them appear more common
than they really are,” Goumas said.
“The
species is actually in decline in the UK, and we hope our ongoing research into
human-gull interactions will contribute to conservation efforts.”
_____
Madeleine
Goumas et al. 2020. Herring gull aversion to gaze in urban and
rural human settlements. Animal Behaviour 168: 83-88; doi:
10.1016/j.anbehav.2020.08.008
