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N
ew research shows that rhinos
get help with their famously poor
eyesight from some feathered friends.
The relationship between oxpeckers and
the large mammals from which they pick
ticks is a complex one. It was long thought
to be a straightforward case of mutual
benefit, until it was realised that the birds
also open wounds and drink their hosts’
blood, suggesting the relationship leans
towards the parasitic.
Now, though, Roan Plotz of Australia’s
Victoria University has discovered that
red-billed oxpeckers provide another
important service for black rhinos – one
that might incline the pachyderms to
tolerate a bit of vampirism: they warn
their hosts of approaching danger.
“Every single time the birds call, the
rhinos respond immediately and almost
always re-orientate to face downwind,”
says Plotz. “Being blind as bats and
reliant on their sense of smell, they
can’t detect people approaching from
that direction.”
His experiments showed that the
presence of oxpeckers more than
doubled the distance at which rhinos
detected approaching humans. Plotz
says the study was inspired by a Swahili
name for the oxpecker, Askari wa kifaru,
which translates as “rhino’s guard.”
He suggests that reintroducing
oxpeckers to areas from which they have
disappeared might help rhinos avoid
poachers: “I’d love to do trials using
people armed with paint-guns to test
that one.”
But there’s another intriguing – if
speculative – possibility that emerges
from Plotz’s work. Many black rhinos
have permanent weeping sores at
specific sites on their flanks, caused by
infection with a parasitic worm. The
oxpeckers feed regularly from these
lesions, and the rhinos are apparently
happy for them to do so.
Plotz suspects that the rhinos may be
managing the worm infections in order
to keep the oxpeckers close.
“The blood may be tiding the
oxpeckers through periods when there
aren’t enough ticks available,” he says.
He even wonders whether the lesions
may represent a very early stage in the
development of a brand new gland
that is evolving in response to the
devastating toll that poaching has had
on rhino populations.
Stuart Blackman