Eur. J. Entomol. 123: 258-266, 2026 | DOI: 10.14411/eje.2026.025

Elevation shapes predation pressure: Evidence from artificial caterpillars in the Italian AlpsOriginal article

Max NARDIN ORCID...
University of Vienna, Faculty of Life Sciences, Vienna, Austria; e-mail: max.nardin99@gmail.com

This study investigated predation pressure along an altitudinal gradient in the Eastern Alps using the sentinel prey method with artificial caterpillars made of green and brown plasticine. The aim was to assess how elevation affects the intensity and composition of predation, distinguishing between invertebrate and vertebrate attacks. A total of 750 models were placed at different elevations between 1300 and 2100 m a.s.l., exposed for 24 h, and then examined for characteristic attack marks. Results showed that, despite lacking natural cues such as odour, movement, and chemical signals, the artificial caterpillars were frequently attacked, confirming the validity of the method. Predation pressure significantly decreased with increasing elevation, with the lowest attack rate recorded at 2100 m and no bird attacks observed at this elevation. Invertebrates were the dominant predator group, while bird attacks were comparatively rare. No significant colour effect was detected. Overall, the findings align with previous literature, supporting the hypothesis that predation decreases at higher elevations, likely due to lower predator densities and harsher environmental conditions.

Keywords: Elevation gradient, artificial prey model, sentinel prey, alpine ecology, predator-prey interactions, bird predation, invertebrate predation

Received: January 2, 2026; Revised: September 1, 2026; Accepted: September 1, 2026; Published online: October 14, 2026  Show citation

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NARDIN, M. (2026). Elevation shapes predation pressure: Evidence from artificial caterpillars in the Italian Alps. EJE, 123, Article 258-266. https://doi.org/10.14411/eje.2026.025
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