DOI: 10.5061/dryad.gtht76hx7
title: Insectivore diet and abundance determine the contribution of bird species to services and disservices in an agricultural ecosystem

description: Insectivorous birds provide an essential ecosystem service in agriculture
 by feeding on arthropods considered pests but can also consume arthropods
 considered to be natural enemies of such pests. Therefore, depending on
 the dietary composition of the birds, intraguild predation could outweigh
 pest control services. This study addressed the agronomic quality, defined
 as the trade-off between ecosystem services (pest control) and disservices
 (intraguild predation), of 26 insectivorous bird species in culturally and
 economically important cider apple orchards in northern Spain. We used
 DNA-metabarcoding techniques to analyze bird’ diets. First, we examined
 whether the trophic position of bird species can be inferred from
 functional traits related to foraging and movement behavior and from the
 degree of insectivory in their diets. Then, we tested whether bird
 abundance and trophic position influenced agronomic quality, based on the
 proportion of arthropod crop pests and natural enemies in their diet.
 Finally, we combined bird abundance, insectivory and agronomic quality to
 infer the potential contribution of each bird species to pest control.
 Bird trophic position was positively related to the degree of insectivory,
 with this effect being modulated by traits related to body size. The
 trophic position of birds was inversely related to their agronomic
 quality. Nevertheless, the agronomic quality only slightly affected the
 differential contribution of bird species to the whole assemblage effect.
 Overall, we found the potential of insectivorous bird species to control
 pests can be estimated based on their trophic position. Yet, in
 agroecosystems with uneven avian species abundance, the potential
 contribution of bird species to pest-control services may be driven by
 their quantitative contribution rather than by the bird’s per capita,
 qualitative effects. Finally, our results suggest that rare insectivorous
 birds may have a redundant role in pest control, due to the overwhelming
 functional dominance of common species.
description: # Insectivore diet and abundance determine the contribution of bird
 species to services and disservices in an agricultural ecosystem
 [https://doi.org/10.5061/dryad.gtht76hx7](https://doi.org/10.5061/dryad.gtht76hx7) ## Description of the data and file structure This dataset contains the data and code necessary to replicate analyses in Jiménez-Albarral et al (2025). The study addresses the agronomic quality, defined as the trade-off between ecosystem services (pest control) and disservices (intraguild predation), of 26 insectivorous bird species in culturally and economically important cider apple orchards in northern Spain. ### Files and variables #### File: Birds\_traits.xlsx **Description:** Trait values of bird species captured in three study apple orchards of Asturias (northern Spain) ##### Variables * Species: Scientific name of the bird species * Sp: Species name Acronym * RAB: Relative abundance, the proportion of individuals recorded across orchards and censuses over the year * TAB: Total abundance, number of individuals recorded across orchards and censuses over the year * INSEC: Degree of insectivory * WEIGHT: Weight (gr) * GAPE: Gape width (mm) * TARSUS: Tarsus length (mm) * KIPP: Kipp’s index (Kipp's distance divided by wing length) * BEAK: Beak length (mm) * TAIL: Tail length (mm) #### File: Birds\_wPOO.xlsx **Description:** Weighted percentage of occurrence (wPOO) values of prey taxa by bird species in three study apple orchards of Asturias (N Spain) ##### Variables * Prey: Scientific name of the prey taxa * Eco_Role: Ecological prey category * Agro_Role: Agronomic prey category * From *Aegithalos caudatus* onwards: Scientific name of the bird species ## Code/software #### File: Jiménez-Albarra\_et\_al\_\_script.R **Description:** The R script to calculate the trade-off estimators of insectivorous birds (trophic position, agronomic quality and proportion of apple pest species consumed) and the potential contribution of bird species to pest control services. It also contains the code to make the PCoA of the traits, to build the models used to analyze the data and to visualize the results.