  We consider the inverse problem of localizing a prey hitting a spider orb-web
from dynamic measurements taken near the center of the web, where the spider is
supposed to stay. The actual discrete orb-web, formed by a finite number of
radial and circumferential threads, is modelled as a continuous membrane. The
membrane has a specific fibrous structure, which is inherited from the original
discrete web, and it is subject to tensile pre-stress in the referential
configuration. The transverse load describing the prey's impact is assumed of
the form $g(t)f(x)$, where $g(t)$ is a known function of time and $f(x)$ is the
unknown term depending on the position variable $x$. For axially-symmetric
orb-webs supported at the boundary and undergoing infinitesimal transverse
deformations, we prove a uniqueness result for $f(x)$ in terms of measurements
of the transverse dynamic displacement taken on an arbitrarily small and thin
ring centered at the origin of the web, for a sufficiently large interval of
time.
