  Formation and competition of associations are studied in a six-species
ecological model where each species has two predators and two prey. Each site
of a square lattice is occupied by an individual belonging to one of the six
species. The evolution of the spatial distribution of species is governed by
iterated invasions between the neighboring predator-prey pairs with species
specific rates and by site exchange between the neutral pairs with a
probability $X$. This dynamical rule yields the formation of five associations
composed of two or three species with proper spatiotemporal patterns. For large
$X$ a cyclic dominance can occur between the three two-species associations
whereas one of the two three-species associations prevails in the whole system
for low values of $X$ in the final state. Within an intermediate range of $X$
all the five associations coexist due to the fact that cyclic invasions between
the two-species associations reduce their resistance temporarily against the
invasion of three-species associations.
