Three rodent species with similar characteristics coexist in the centre of the Iberian Peninsula
(Wood mouse Apodemus sylvaticus, Algerian mouse Mus spretus and Common vole Microtus
arvalis). This study examines if habitat segregation exists between the species, as a means
of preventing the intense competition that may exclude any of these species. One of the
three species recently arrived in the area. The other two have been consuming resources for
a long time. Our aim is to check whether adaptations have been acquired during this time.
To do this, we placed the three rodent species in semi-wild enclosures consisting of three
different habitats and fed them acorns from the two most abundant oak species of the area
for one week. We estimated the number of acorns and the mass per acorn that each species
consumed in each habitat. It was found that each species prefers different habitats. The
two species that were first installed in the area participated in acorn dissemination through
transport and storage. They also conserved the embryos of the acorns consumed. The newly
arrived species did not transport acorns and destroys them during consumption, behaving
as a true predator species. The three species segregate their habitats to avoid competition.
The two species that have been in the area for a longer time exhibit a relationship with the
oaks that is akin to mutualism.
