We study the dynamics of a second-order difference equation that is derived
from a planar Ricker model of two-stage (e.g. adult, juvenile) biological
populations. We obtain sufficient conditions for global convergence to zero in
the non-autonomous case. This gives general conditions for extinction in the
biological context. We also study the dynamics of an autonomous special case of
the equation that generates multistable periodic and non-periodic orbits in the
positive quadrant of the plane.Comment: 26 pages, 2 figures - accepted for publication in the Journal of
Difference Equations and Application