Diversity and patterns of marine non‐native species in the archipelagos of Macaronesia

Abstract

Aims The present study is the first attempt to grasp the scale and richness of marine biological invasions in Macaronesia. We pioneered a comprehensive non‐native species (NNS), inventory in the region to determine their diversity patterns and native distribution origins. NNS were defined here as the result of both introductions and range expansions. We also used statistical modelling to examine relationships among NNS richness, anthropogenic activities, demographic and geographical variables across Macaronesia. Location Macaronesia. Methods A comprehensive literature search was conducted for marine NNS records in Macaronesia, registering the first record's location and year from 1884 to 2020. We used univariate and multivariate analyses to evaluate differences and similarities in community composition. By applying a Generalized Linear Model (GLM), we tested hypotheses regarding NNS richness as a function of anthropogenic activities, demographic and geographical variables. Results A total of 144 marine non‐native species (NNS) were recorded for the whole of Macaronesia. The highest NNS richness was registered in the Canary Islands (76 NNS), followed by the Azores (66 NNS), Madeira (59 NNS) and finally Cabo Verde (18 NNS). Some differences amongst archipelagos were observed, such as the high number of non‐native macroalgae in the Azores, fishes in the Canary Islands and tunicates in Cabo Verde. Overall, macroalgae, tunicates and bryozoans were the predominant taxonomic groups in the Macaronesian archipelagos. Madeira and Canary Islands were the archipelagos with more similarity in marine NNS, and Cabo Verde the most divergent. Finally, GLM suggested that non‐native richness patterns across Macaronesia were dependent on the considered archipelago and strongly affected by (1) minimum distance to the mainland, (2) the total number of ports and marinas and (3) total marinas area (km2). Conclusions The model results and NNS listing in the present study will likely raise the awareness and response regarding marine NNS in the whole Macaronesia region, serving as a baseline for future research as well as implementing and enforcing regulations related to the introduction of marine NNS in oceanic islands.

Decoding the spread of non-indigenous fishes in the Mediterranean Sea

“…The last five decades marine scientists started to intensively explore the phenomenon of marine biological invasions that imperil marine ecosystems. Several pioneer study efforts have investigated non-indigenous species’ patterns, pathways and impacts in the Mediterranean Sea and its adjacent regions 6 , 30 , 31 . In parallel with theoretical and baseline knowledge, the nature of historical spatio-temporal patterns of NIS introductions is equally significant to assess their spread 32 and temporal variability 28 , by also contributing to biogeographic and macroecological research.…”

From Plates to Baits: Using a Remote Video Foraging System to Study the Impact of Foraging on Fouling Non-Indigenous Species

“…The identified fouling species were classified by major taxa, morphology (encrusting, massive and arborescent) and status (native, cryptogenic and NIS). Species status was assigned based on the existing literature [44,[51][52][53][54][55][56][57][58][59][60][61][62][63][64][65][66][67].…”

“…T1: uncaged; T2: caged 15 mm mesh; T3: caged 1 mm mesh; Table S1: Fish species sighted inside the marina of Quinta do Lorde; Table S2: Fouling taxa and their mean percent coverage on each treatment before and after being exposed to foraging during the remote video foraging system (RVFS) trials, including the references used for their identification and previous records for the archipelago of Madeira. Species status was assigned using the most updated list [52]. C = Cryptogenic species; N = Native species; NIS = Non-indigenous species; U = Unresolved taxa; T1 = Treatment 1 (uncaged); T2 = Treatment 2 (caged with 15 mm mesh); T3 = Treatment 3 (caged with 1 mm mesh); Bef = Before predation; Aft = After predation; Table S3: PERMANOVA results on the relative abundance of NIS and native species among treatments before and after Remote Video Foraging System (RVFS) trials.…”

Expanding north: first record of the beaded sea cucumber Euapta lappa at Madeira Island

“…In the East Atlantic, it has been recorded from São Tomé and Príncipe northwards to the Selvagens Islands, including the archipelagos of Cabo Verde and the Canary Islands (Pérez-Ruzafa et al ., 1999, 2002; Wirtz, 2003; Entrambasaguas et al ., 2008). In recent years an increasing number of non-indigenous species (NIS) has been recorded at Madeira Island (Castro et al ., 2022), with many representing northern range expansions (e.g. Wirtz & Berenger, 2017; Ribeiro et al ., 2019; Schäfer et al ., 2019; Castro et al ., 2021).…”