Monitoring arthropods under the scope of LIFE-Snails project – Baseline Data

Abstract

The database we present is part of the LIFE SNAILS project (Support and Naturalization in Areas of Importance for Land Snails), which has the main aim of protect three species of terrestrial molluscs, two snails (Oxychilus agostinhoi and Leptaxis minor) and a semislug (Plutonia angulosa), which are endemic of Santa Maria Island, and whose populations are at high risk. In this study, we established a comprehensive database derived from a long-term arthropod monitoring campaign utilizing SLAM (Sea, Land, Air, Malaise) traps. While molluscs were not the focus, our findings present a credible proxy for assessing the overall habitat quality for endemic invertebrates, using arthropods as principal indicators. Between September and December of 2022, a total of 11 SLAM traps were installed and monitored monthly in eleven sites of mixed forests of Santa Maria Island. Based on the 33 available samples (11 sites x 3 months), we registered 94 identified taxa. A total of 21 species were endemic, 31 native non-endemic, 32 introduced and 10 indeterminate. This publication not only contributes to the conservation of highly threatened endemic molluscs, through an assessment of habitat quality based on arthropod communities and habitat description (e.g. native or exotic vegetation), but also provide an updated inventory of arthropods from Santa Maria Island.