Data from: Intraguild predation in pioneer predator communities of Alpine glacier forelands

Pioneer communities establishing themselves in the barren terrain in front
of glacier forelands consist principally of predator species such as
carabid beetles and lycosid spiders. The fact that so many different
predators can co-inhabit an area with no apparent primary production was
initially explained by allochthonous material deposited in these
forelands. However, whether these populations can be sustained on
allochthonous material alone is questionable and recent studies point
towards this assumption to be flawed. Intraguild predation (IGP) might
play an important role in these pioneer predator assemblages, especially
in the very early successional stages where other prey is scarce. Here, we
investigated IGP between the main predator species and their consumption
of Collembola, an important autochthonous alternative prey, within a
glacier foreland in the Ötztal (Austrian Alps). Multiplex PCR and stable
isotope analysis were used to characterize the trophic niches in an early
and late pioneer stage over two years. Results showed that intraguild prey
was consumed by all invertebrate predators, particularly the larger
carabid species. Contrary to our initial hypothesis, the DNA detection
frequency of IGP prey was not significantly higher in early than in late
pioneer stage, which was corroborated by the stable isotope analysis.
Collembola were the most frequently detected prey in all of the predators
and the overall prey DNA detection patterns were consistent between years.
Our findings show that IGP appears as a constant in these pioneer predator
communities and that it remains unaffected by successional changes.