Spatiotemporal and ecological distribution of megabenthic non-crustacean invertebrates in an ultra-oligotrophic gulf, the eastern Mediterranean Sea

Çanakkale Onsekiz Mart University Journal of Marine Sciences and Fisheries

2021

Self Cite

During 2009During -2010 epifaunal materials were collected seasonally with a beam trawl from seven fixed stations in the infralittoral of Gulf of Izmir to study spatiotemporal distribution of megabenthic fauna and their ecology. A total 153 megafaunal species were identified belonging to nine phyla, comprised mostly of 54 molluscans, 43 chordates (mostly fish), 20 arthropods, and 18 echinoderms. Nine alien species were recorded. Four species (two fish species, one gastropod and one Asteroidea species) were constant species and 16 species were common species in the study area. Lesueurigobius friesii, Buglossidium luteum, Turritellinella tricarinata and Astropecten irregularis were the most frequently occurred, and Lesueurigobius friesii, Varicorbula gibba, Anomia ephippium, Turritellinella tricarinata and Dentalium sp were the most abundantly occurred species. Excluding the evenness index, faunistic characteristics tended to increase as a factor of depth. Seasonal density (abundance and biomass) was minimal in April and maximal in February, followed by November having 2-fold higher abundance than that inJuly. Faunal assemblages were correlated with regions of the gulf and habitat type. Buglossidium luteum overspread the entire gulf excluding the inner gulf. Varicorbula gibba and Fulvia fragilis, a pollution indicator predominated the inner gulf. Hydrographical parameters and depth were associated to dictate faunal assemblages with difference among the sectors and habitats.

Section: Faunal Community and Ecologymentioning

confidence: 96%

Section: Introductionmentioning

confidence: 99%

Ecological Gradients of Epimegafaunal Distribution along The Sectors of Gulf of İzmir, Aegean Sea

Çanakkale Onsekiz Mart University Journal of Marine Sciences and Fisheries

2021

Self Cite

Ecological Indicative Stressors of Native vs. Non-Native Fish in an Ultra-Oligotrophic Region of the Mediterranean Sea

Meo²,

Miglietta³

et al. 2023

Sustainability

In the present study, we investigated the different ecological characteristics of native and non-native demersal fish collected in 2014–2015 on the shelf of the Antalya Gulf in the Eastern Mediterranean Sea. Lessepsian migrants originating from the Indo-Pacific Ocean were classified as non-indigenous species (NIS) and the other species, which were mostly Atlanto-Mediterranean, were classified as indigenous species (IS). The results showed that the faunistic characteristics of IS and NIS differed significantly in space but only partly over time. The density and species diversity of the IS increased with the seafloor depth, while the opposite pattern was observed for the NIS, which were found mostly in shallow waters. Proximity to rivers and Posidonia oceanica meadows and the presence of a marine protected area (MPA) were also important factors determining the differences in the ecological characteristics of IS and NIS. The ecological ordination of the fish assemblages in the canonical correspondence analysis (CCA) space was V-shaped for the IS and =-shaped for the NIS, and it was mainly determined by bottom depth. Altogether, the ordination took the shape of a double strikethrough (V) due to the NIS filling an available niche. Hierarchically, the NIS (“occupiers”) and IS (“resisters”) shared the shallowest waters, while the middle-shelf waters were occupied by NIS (“gapers”) and IS (“escapers”) separately. The upper shelf was occupied only by IS (“homekeepers”) and “minorities” of NIS. Finally, we identified eight factors as ecological indicators of NIS and IS: bottom depth, bottom vegetation status, fish hierarchy, key species, water productivity, fish trophic level, life strategy and morphometry.

Keystone Porgy Species (Sparidae) Overcome the Alien Randall's Threadfin Bream (Nemipterus randalli) for Catch Balance in Space on An Oligotrophic Levant Shelf or Vice Versa?

Çanakkale Onsekiz Mart University Journal of Marine Sciences and Fisheries

Meo²,

Miglietta³

et al. 2022

Since 2008 spatiotemporal and ecological distributions of porgies (sparid, all indigenous fish) were examined in the presence or absence of Randall's threadfin bream, Nemipterus randalli in the present study area. Seasonal fish and environmental parameters samplings were conducted at three transects of the fishing (nMPA) or non-fishing (MPA) regions on an oligotrophic shelf (Levantine Sea) in 2014-2015 for understanding management and ecology of the porgies’ catches. Of 13 sparid fish determined during the present study, five species are rarely found. There were no seasonal significant differences in densities of the sparid fish with or without the alien nemipterid fish. However, there were differences in the densities by the bottom depths, the regions, and soft and hard bottoms vegetated by Caulerpa spp and meadow, respectively. Ecologically, fish assemblages and faunistic characters of the sparid fish were highly variable when excluding the N. randalli as highlighted and follows; i) seasonal variation occurred and ii) the depthwise community assemblages became irregular. N. randalli seemed to balance the sparid catch attributed to the biomass-abundance ratio in the ecosystem or vice versa in this trophically sensitive gulf (ultra-oligotrophic) of the eastern Mediterranean Sea.