Response of the Black Sea Zooplankton to the Marine Heat Wave 2010: Case of the Sevastopol Bay

Abstract

Global warming is increasing the frequency and severity of the marine heat waves, which poses a serious threat to the marine ecosystem. This study analyzes seasonal and interannual dynamics in the abundance and structure of the mesozooplankton community in Sevastopol Bay based on bi-monthly routine observations over 2003–2014. The focus is on the impact of the summer 2010 marine heat wave (MHW2010) on crustaceans belonging to different ecological groups. As a response to the MHW2010, three warm-water species (O. davisae, A. tonsa and P. avirostris) exhibiting the maximum seasonal density in latter summer showed a sharp increase in the annual abundance and their share in the mesozooplankton community. The increase in the annual abundance in 2010 of the eurythermal species P. parvus and P. polyphemoides exhibiting seasonal peaks in spring and autumn is not related to the MHW2010 but can be explained by a rise of temperature in the first part of the year. O. davisae and A. tonsa showed the most pronounced response among the species to the MHW2010, confirming that non-native species exhibited great flexibility as an adaptive response to environmental changes, especially in the case of climate warming. Among crustaceans observed in this study, O. davisae can be considered as an indicator of the environmental conditions associated with the warming of the Black Sea and the Mediterranean basin as a whole.

Romanian Black Sea Mesozooplankton’s Seasonal Dynamics and Distribution during 2013-2020

“…According to Sakalli and Basusta (2017) in the last 34 years , most of the monthly Black Sea temperature fluctuations were during summer and autumn (Sakalli et al, 2018). Mesozooplankton comprises poikilothermic animals, sensitive to temperature changes, which is one of the most important factors, driving its temporal and spatial distribution (Gubanova et al, 2022). The analysis of the mesozooplankton community from the Romanian Black Sea coast highlighted variations both from qualitative and quantitative point of view.…”

Ecology of Marine Zooplankton

“…Zooplankton communities are investigated in studies by Gubanova et al [12] and Chaigneau et al [13], respectively, in response to climate change and seasonal variations in the Black Sea and a lagoon in West Africa, areas where little is known about the zooplankton diversity. Gubanova et al [12] assess the response of the mesozooplankton community in Sevastopol Bay, a semi-enclosed estuarine-type bay, to the most persistent and intense marine heat wave recorded in the Black Sea (summer 2010).…”

“…Zooplankton communities are investigated in studies by Gubanova et al [12] and Chaigneau et al [13], respectively, in response to climate change and seasonal variations in the Black Sea and a lagoon in West Africa, areas where little is known about the zooplankton diversity. Gubanova et al [12] assess the response of the mesozooplankton community in Sevastopol Bay, a semi-enclosed estuarine-type bay, to the most persistent and intense marine heat wave recorded in the Black Sea (summer 2010). Using long-term routine observations (2003-2014), the study reports seasonal variations in zooplankton composition, abundance, and structure; warm water and non-native species (e.g., Oithona davisae and Acartia tonsa) showed the maximum seasonal density, suggesting their greater flexibility to adapt in response to environmental changes.…”