Data from: Functional responses of an apex predator and a mesopredator to an invading ungulate: Dingoes, red foxes and sambar deer in south-east Australia

Biological invasions by large herbivores involve the establishment of
novel interactions with the receiving mammalian carnivore community, but
understanding these interactions is difficult due to the large
spatiotemporal scales at which such dynamics would occur. We quantified
the functional responses of a native apex predator (the dingo (Canis
familiaris), which includes wild dogs and their hybrids) and a non-native
mesopredator (red fox; Vulpes vulpes) to an invading non-native ungulate
(sambar deer; Cervus unicolor) in Australia. We predicted that the apex
predator would exhibit a stronger functional response to increasing sambar
deer abundance than the mesopredator. We used a state–space model to link
two 30-year time series: (i) sambar deer abundance (hunter
catch-per-unit-effort); and (ii) percentages of sambar deer in dingo (N =
4531) and fox (N = 5002) scats. Sambar deer abundance increased over
fourfold during 1984–2013. The percentages of sambar deer in dingo and fox
scats increased during this 30-year period, from nil in both species in
1984 to 8.2% in dingoes and 0.5% in foxes in 2013. Dingoes exhibited a
much stronger functional response to increasing sambar deer abundance than
foxes. The prediction that invading deer would be utilized more by the
apex predator than by the mesopredator was therefore supported. The
increasing abundance of sambar deer during the period 1984–2013 provided
an increasingly important food source for dingoes. In contrast, the
smaller red fox utilized sambar deer much less. Our study demonstrates
that prey enrichment can be an important consequence of large herbivore
invasions and that the effect varies predictably with the trophic position
of the mammalian carnivores in the receiving community.