Summary

Background
Organic orchards and their associated hedgerows can function as important ecological infrastructures in agricultural landscapes by providing shelter, prey resources, floral resources and refuge sites for arthropods, including predators and parasitoids involved in biological control. These habitats may support diverse arthropod communities and contribute to the suppression of pest populations below economically damaging levels.

Characterising arthropod assemblages is, therefore, important for understanding the biodiversity associated with agricultural systems and for supporting future research on biological control.

Such information is particularly relevant on oceanic islands, where geographical isolation, high levels of endemism and ongoing introductions of non-native species shape community composition and ecosystem functioning. Furthermore, island agricultural landscapes often comprise relatively small and fragmented habitat patches, making semi-natural elements, such as hedgerows, particularly important for maintaining biodiversity and supporting ecosystem services. Biodiversity-friendly agricultural practices may, therefore, contribute simultaneously to biodiversity conservation, ecosystem-service provision and the early detection of potentially invasive species.

Under the scope of the BIODIVERSA+ COMCHA project, arthropod assemblages were sampled in six organically managed mixed orchards and adjacent hedgerows on Terceira Island, Azores, Portugal, generating a dataset that enables future comparisons of community composition and diversity between these habitat types. Sampling was conducted in September 2025 and May 2026 using standardised methods, including SLAM (Sea, Land and Air Malaise) traps, nocturnal active aerial searches, nocturnal foliage beating and diurnal foliage beating. The resulting Darwin Core Archive is composed of Event and Occurrence tables and provides baseline information on arthropod diversity in island agroecosystems, constituting a valuable resource for future biodiversity monitoring and biological control research.

New information
We provide an inventory of arthropods collected in EU-certified organic orchards and surrounding hedgerows on Terceira Island, based on 46 sampling events in September 2025 and 36 sampling events in May 2026 (82 sampling events in total), distributed across six localities and two habitat types: Mixed Orchards and Mixed Hedges.

During September 2025 and May 2026, a total of 15,739 specimens were recorded in 1,863 occurrences records, representing four arthropod classes, 18 orders and 86 families.

Of these specimens, 13,854 were identified to species or subspecies level, corresponding to 196 taxa. Overall, the dataset includes 299 morphospecies or taxonomic units.

Amongst these specimens, 10,596 specimens were recorded in 1,300 occurrence records in September 2025, while 5,143 specimens were recorded in 563 occurrence records in May 2026. The identified species/subspecies include 11 endemic taxa, 57 native non-endemic taxa, 104 introduced taxa and 24 taxa of uncertain origin. In terms of abundance, native non-endemic taxa were dominant, followed by introduced, endemic and uncertain colonization taxa. This dataset includes four species that are new records for Terceira Island: Dipoena melanogaster (C.L. Koch, 1837) (Araneae, Theridiidae), Textrix pinicola Simon, 1875 (Araneae, Agelenidae), Stenocaecilius caboverdensis (Meinander, 1966) (Psocodea, Caeciliusidae) and Euconnus campestris campestris (L.W. Schaufuss, 1866) (Coleoptera, Staphylinidae). These records expand current knowledge of the arthropod fauna of Terceira Island and contribute to a more comprehensive understanding of the biodiversity associated with organic orchards and adjacent hedgerows. Such baseline information is valuable for future studies investigating arthropod-mediated ecosystem services, including conservation biological control.

The dataset provides a first standardised baseline for comparing arthropod assemblages between orchard interiors and hedgerows in organic fruit-production systems on Terceira Island, supporting future assessments of biological control potential, habitat management, biosecurity surveillance and Nature-based Solutions in insular agroecosystems.