Can seabirds detect infrasound? And if yes,
do they use it to navigate the vast oceans?
A physiological ecologist from Stellenbosch
University (SU), Dr Susana Clusella-Trullas, will be charting unsailed waters
as she sets out to answer this question in collaboration with a team of
researchers from the USA, the United Kingdom (UK) and The Netherlands.
They have recently obtained a grant of R1.3
million from the International Human Frontier Science Program as part of its Young
Investigator Grants for
research into complex mechanisms of living organisms.
Seabird migration remains one of the phenomena
in the animal kingdom that we still know very little about. Over the years
scientists have managed to prove that some birds use the position of the stars
and the earth’s magnetic field to find their way. More recently, a group from
of Oxford, Barcelona and Pisa, demonstrated that shearwaters rely on their sense of smell to find
their way back to their nests on land after foraging out over the ocean.
Dr Clusella-Trullas will be working with Jelle Assink, a geophysicist from the Royal Netherlands
Meteorological Institute in The Netherlands; Samantha Patrick, a behavioral
ecologist from the University of Liverpool in the UK; and Mathieu Basille, a spatial
ecologist from the University of Florida in the USA.
The idea is to pool all their expertise in
order to tackle this vexing question from every possible angle.
“As the physiological ecologist in the team,
I will be examining the ear structures of various seabird species to test this hypothesis.
Since some seabirds have tremendously long migrations, it is highly possible
that they use infrasound as a medium to orientate, avoid storms and detect
island shores. There are a few studies that suggest that homing pigeons can
detect infrasound and some structures and mechanisms have been described for
this group,” she explains.
As seabirds are often found as by-catch in
fisheries, she will be obtaining fresh carcasses from various sources to do the
research: “We will examine cross sections of the inner ear of these seabirds.
Hopefully we will be able to identify the mechanisms that allow them to detect
As part of this process, she will also use 3D
imaging techniques to look for the structures.
If they are able to identify the mechanisms
that allow seabirds to detect infrasound, these will then be visualised and
measured. The data will then be integrated by means of spatial modelling with data
from the larger international collaborative project.
For more information about the project and
their progress, visit the blog at https://seabirdsound.wordpress.com/
On the photo above, Dr Susana Clusella-Trullas from SU's Department of Botany and Zoology. Photo: Stefan Els