TY - JOUR
T1 - Effects of isolation on invertebrate biodiversity among the bladderwrack Fucus vesiculosus
AU - Blanc, Jean-François
AU - Rinne, Henna
AU - Salovius-Laurén, Sonja
PY - 2024/7
Y1 - 2024/7
N2 - Geographic isolation is a factor that is known to affect species composition and diversity in marine systems. In this study, we tested the effects of geographic isolation on invertebrate fauna living among the belt-forming foundation species Fucus vesiculosus in the northern Baltic Sea. Sampling was carried out on reefs with varying levels of isolation (0.5, 1 and 2 km) in July 2021 in the Åland islands (between 59.96°N 20.24°E and 59.75°N 20.84°E). The total number of taxa, abundance, Shannon-Wiener index, Pielou’s evenness and biomass were calculated and the effects of isolation were tested using generalised linear models. Multivariate methods were used to analyse differences in the invertebrate community composition. Although the number of taxa and Shannon´s diversity index did not vary along the isolation gradient, the total abundance of fauna decreased with increasing isolation. In addition, some taxa-specific patterns were observed, e.g. the abundance of insect larvae decreased with isolation while isopods were more numerous in the most isolated locations. As diversity and the number of taxa were similar regardless of isolation, shallow Fucus vesiculosus belts likely act as important biodiversity refuges and potential stepping-stones for invertebrates in remote outer archipelago areas. In a changing climate, these kinds of refuges aiding species dispersal are likely to be even more important, and should be considered in conservation planning.
AB - Geographic isolation is a factor that is known to affect species composition and diversity in marine systems. In this study, we tested the effects of geographic isolation on invertebrate fauna living among the belt-forming foundation species Fucus vesiculosus in the northern Baltic Sea. Sampling was carried out on reefs with varying levels of isolation (0.5, 1 and 2 km) in July 2021 in the Åland islands (between 59.96°N 20.24°E and 59.75°N 20.84°E). The total number of taxa, abundance, Shannon-Wiener index, Pielou’s evenness and biomass were calculated and the effects of isolation were tested using generalised linear models. Multivariate methods were used to analyse differences in the invertebrate community composition. Although the number of taxa and Shannon´s diversity index did not vary along the isolation gradient, the total abundance of fauna decreased with increasing isolation. In addition, some taxa-specific patterns were observed, e.g. the abundance of insect larvae decreased with isolation while isopods were more numerous in the most isolated locations. As diversity and the number of taxa were similar regardless of isolation, shallow Fucus vesiculosus belts likely act as important biodiversity refuges and potential stepping-stones for invertebrates in remote outer archipelago areas. In a changing climate, these kinds of refuges aiding species dispersal are likely to be even more important, and should be considered in conservation planning.
KW - Faunal communities
KW - Rocky shore
KW - Shannon-Wiener diversity index
KW - Coastal ecosystems
KW - Baltic Sea
U2 - 10.1007/s00227-024-04485-4
DO - 10.1007/s00227-024-04485-4
M3 - Article
SN - 0025-3162
VL - 171
JO - Marine Biology
JF - Marine Biology
M1 - 170
ER -