Monthly monitoring of Azorean forest arthropods testing for edge effects (Terceira Island, Azores, Portugal)

The data we present consists in an inventory of arthropods collected in three areas of a native forest fragment at Terra-Brava protected area (Terceira, Azores, Portugal): (i) in the edge of the forest, closer to pasturelands; (ii) in the deepest and pristine part of the native fragment (more than 500 m from edge); (iii) and in an intermediate area (150 from edge), in order to test the edge effect on Azorean arthropod community. The study was carried out between June 2014 and December 2015, in Terceira Island (Azores). A total of nine passive flight interception SLAM traps were deployed, during 18 consecutive months, collecting monthly the arthropods belonging to Arachnida, Diplopoda, Chilopoda and Insecta Classes. This publication provides new information about Azorean arthropods communities across gradients of temporal and edge effect variation

The study area comprises a fragment of native forest “Terra Brava” located in the interior of Terceira island (coordinates: 38° 43' 17"; -27° 13' 14"), in the Azores archipelago. The native forest fragment is covered by native vegetation, mainly by Juniperus brevifolia, Erica azorica, Laurus azorica and Ilex azorica, between others. In general, the climate of the archipelago is temperate oceanic, with frequent and abundant precipitations, high degree of relative humidity and persistent winds, mainly during the winter and autumn seasons

The data collection was performed using Passive flight interception SLAM traps (Sea, Land and Air Malaise trap). Trap size is of approximately 110 x 110 x 110 cm. The trap functioning consists on that the intercepted arthropods crawl up the mesh and then fall inside the sampling recipient, which is filled with propylene glycol (pure 1,2-PROPANODIOL) (Borges et al., 2017). This protocol is adequate to capture flying and non-flying arthropod species (Borges et al., 2017). This sampling protocol was recently used to study diversity and abundance variations in the communities of arthropod on Azorean native areas (Matthews et al., 2019, Borges et al., 2020). A total of nine SLAM traps were deployed in a fragment of native forest of Terceira Island, three of which on the edge of the forest, three on intermediate depth and three on the most pristine part of the forest. The traps samples were collected each month, during 18 consecutive months (from July 2014 to December 2015).

A large number of students financed by the EU Programs ERASMUS and EURODYSSÉE sorted the samples prior to species assignment This manuscript was also partly financed by Portuguese FCT-NETBIOME –ISLANDBIODIV grant 0003/2011 (between 2012 and 2015), Portuguese National Funds, through FCT – Fundação para a Ciência e a Tecnologia, within the project UID/BIA/00329/2013-2020, and AZORESBIOPORTAL –PORBIOTA (ACORES-01-0145-FEDER-000072) (2019). The Natural Park of Terceira provided the necessary authorization for sampling. The database management and Open Access was funded by the project “MACRISK-Traitbased prediction of extinction risk and invasiveness for Northern Macaronesian arthropods” Fundação para a Ciência e a Tecnologia (FCT) - PTDC/BIA-CBI/0625/2021 (2022-2024).