Akademik Veri Yönetim Sistemi
Marine Biodiversity, cilt.54, ss.1-18, 2024 (SCI-Expanded)
Chondrichthyans are a very important taxon that plays a top predator role in the trophic level of the food web, and species
are particularly vulnerable to exploitation in the marine ecosystem. The deep waters of the eastern Mediterranean Sea have
been less studied than the continental shelf, especially for the chondrichthyans. Therefore, the present study was conducted
to investigate the spatio-temporal distribution of chondrichthyans collected monthly in eight different (200–900 m) depth
strata during different periods (2010–2011 and 2019–2021) using an otter bottom trawl. A total of 17 species were identified
in upper bathyal, composed of 6 batoids, 10 sharks, and one chimaera. The constant species (dominance: DO% > 50) in
the study area were Galeus melastomus, Scyliorhinus canicula, Etmopterus spinax, and Raja clavata. The most abundant
species was E. spinax, followed by G. melastomus. Fourteen and 15 species were caught during the first and the second
survey, respectively. Biodiversity characteristics (number of species, abundance, and diversity indices) varied only with
bottom depth. Two different depthwise assemblages were estimated along the bottom depth gradient; ≤ 500 m and > 500 m.
The discriminator species were R. clavata, S. canicula, G. melastomus, Dipturus oxyrinchus, and Squalus blainville found
on the upper slope and E. spinax, G. melastomus, and Centrophorus cf. uyato found on the lower slope. With our results,
total number of demersal chondrichthyan species found in the bottom (bathyal and continental shelf) of Antalya Bay was
reached to 26 species.