Syntopic Cystoseira taxa support different molluscan assemblages in the Gulf of Naples (southern Tyrrhenian Sea)

Abstract

Brown macroalgae belonging to the genus Cystoseira (Fucales: Sargassaceae) are canopy-forming organisms the recent decline of which at a basin and local scale has been widely documented, which urgently calls for research to fill knowledge gaps and support new and effective measures for protection. We, hereby, characterised the molluscan assemblages associated with three Cystoseira taxa (C. amentacea, C. compressa and C. crinita) from Ischia Island (Italy, Tyrrhenian Sea), and tested whether different congeneric taxa may syntopically support a different biota. In particular, these assemblages were compared among three Cystoseira species, between two times of sampling (June–July 2015 and June–July 2016), and among six sites in terms of multivariate structure (identity and relative abundances of constituting taxa combined, and presence–absence composition), as well as for synthetic measures of diversity, including the total richness of taxa, the exponential Shannon index and the reciprocal Simpson index. In total, 24736 molluscan individuals were collected, overall belonging to 52 taxa. The majority of the identified species included micrograzers and filter feeders, which is in agreement with similar previous studies. The composition of associated molluscan assemblages, which was mainly represented by juvenile individuals, differed among the three Cystoseira species, suggesting that even congeneric taxa do not support an analogous benthic fauna. The present findings have shed light on the molluscan biota associated with Cystoseira taxa in the Gulf of Naples and strengthened the importance of such habitat-forming macroalgae in structuring the local infralittoral invertebrate biodiversity and as a nursery for species-specific associated molluscs.

Unusually Warm Summer Temperatures Exacerbate Population and Plant Level Response of Posidonia oceanica to Anthropogenic Nutrient Stress

“…Experimental sites S3 (40.7354°N, 13.9646°E) and S4 (40.7063°N, 13.9567°E) were located off the island of Ischia, which is a marine protected area since 2007 ( Chiarore et al, 2019 ). However, Ischia attracts more than four million tourists per year with the majority visiting the island between May and September ( Tomicic et al, 2001 ; Carlino et al, 2011 ).…”

Does Warming Enhance the Effects of Eutrophication in the Seagrass Posidonia oceanica?

“…Because of their proximity, both locations experienced similar Sea Surface Temperature (SST) regimes. The island of Ischia is a marine protected area since 2007, whereas the Gulf of Pozzuoli is heavily impacted by human activities (Tornero and Ribera d'Alcalà, 2014;Chiarore et al, 2019). The Bacoli sampling site was close to the city of Bacoli and to the one of Baia, an important commercial harbor since Roman age.…”

Addressing reproductive stochasticity and grazing impacts in the restoration of a canopy‐forming brown alga by implementing mitigation solutions

“…Cystoseira forests provide critical ecosystem services in littoral habitats by increasing the complexity of rocky bottoms and thus supporting rich biodiversity and complex food webs (e.g. Sauvageau, 1912;Funk, 1927;Boudouresque & Lück, 1972;Giaccone, 1973;Ballesteros, 1988;Rull & Gómez Garreta, 1989;Otero-Schmitt & Pérez-Cirera, 1996;Ballesteros et al, 1998;Pizzuto, 1999;Ballesteros et al, 2009;Cheminée et al, 2013;Pitacco et al, 2014;Chiarore et al, 2019;Cuadros et al, 2019).…”