Spring composition of the macroalgal vegetation of a small offshore island in the north-western Mediterranean (Gallinara Island, Ligurian Sea)

By

Rindi, Fabio
Gavio, Brigitte
Pezzolesi, Laura
Pica, Daniela
Ponti, Massimo
Torsani, Fabrizio
Cerrano, Carlo

Type

Article

Date of Publication

2022-5-27

Original Publication

Italian botanist

Volume

13

Pages

45--65

Subjects

Biotic homogenization , Macroalgal floras , Marine protected areas , Mediterranean Sea , non-indigenous species

Contributed by

Pensoft Publishers

Language

English

Published by

Sofia, Bulgaria Pensoft 2016-

Identifiers

DOI: https://doi.org/10.3897/italianbotanist.13.81812

 

Abstract

Gallinara Island, a small island located 1.5 km off the shore of Liguria (Italy, north-western Mediterranean Sea) was included in a list of proposed Marine Protected Areas (MPA) in the early 90s. Since then, its benthic assemblages have been studied in detail and the main macrophytic communities have been mapped. A detailed assessment of its benthic macroalgal flora, however, has never been made. Gallinara was visited in the course of 5 consecutive years and its macroalgal flora was studied based on collections made by snorkelling and SCUBA diving. Overall, 141 macroalgal taxa were collected and identified (23 Chlorophyta, 94 Rhodophyta, 24 Ochrophyta); 91 of them represent new records for the island. One of the most notable new records is the non-indigenous red alga Womersleyella setacea, previously unreported from the island and widely distributed, particularly on the south-eastern shore. Observations made in the course of the surveys confirm the rarefaction of some large-sized brown algae (particularly Sargassum vulgare) but indicate also that others previously reported as rare (Cystoseira compressa, Dictyopteris polypodioides) are still common on the island.