Much can happen in three months: The proliferation of the bigfin reef squid (Sepioteuthis lessoniana Lesson, 1831) within Maltese coastal waters since its first record

Abstract

The rapid colonisation of Maltese coastal waters by the non-indigenous Sepioteuthis lessoniana Lesson, 1831 is hereby documented through the ‘Spot the Alien’ citizen science campaign, to which a considerable number of catches and sightings of the species were submitted in rapid sequence over a three-month timeframe. The study also compares sea surface temperature values for the July-December period of 2015, 2020 and 2025 for the same waters, in order to explore the putative influence that sea temperatures might have on the observed rapid expansion of this non-indigenous species (NIS). The findings of this study highlight both the notable spread of the species across local waters and the important role of citizen science in early detection and monitoring of non-indigenous species.