Annual rhythms of temporal niche partitioning in the Sparidae family are correlated to different environmental variables
Sbragaglia, Valerio . et al.-- 11 pages, 5 figures, 2 tables, supplementary information https://doi.org/10.1038/s41598-018-37954-0 ; The seasonal timing of recurring biological processes is essential for organisms living in temperate regions. While ample knowledge of these processes exists for terrestrial environments, seasonal timing in the marine environment is relatively understudied. Here, we characterized the annual rhythm of habitat use in six fish species belonging to the Sparidae family, highlighting the main environmental variables that correlate to such rhythms. The study was conducted at a coastal artificial reef through a cabled observatory system, which allowed gathering underwater time-lapse images every 30 minutes consecutively over 3 years. Rhythms of fish counts had a significant annual periodicity in four out of the six studied species. Species-specific temporal patterns were found, demonstrating a clear annual temporal niche partitioning within the studied family. Temperature was the most important environmental variable correlated with fish counts in the proximity of the artificial reef, while daily photoperiod and salinity were not important. In a scenario of human-induced rapid environmental change, tracking phenological shifts may provide key indications about the effects of climate change at both species and ecosystem level. Our study reinforces the efficacy of underwater cabled video-observatories as a reliable tool for long-term monitoring of phenological events ; VS was supported by a Leibniz-DAAD postdoctoral research fellowship (n. 91632699). [.] This work was partially funded within the framework of the RESBIO project (REdes de Sensores submarinos autónomos y cableados aplicados a la monitorización remota de indicadores BIOlógicos; Comisión Interministerial de Ciencia y Tecnología, MINISTERIO DE ECONOMÍA, INDUSTRIA Y COMPETITIVIDAD, RETOS 2017) under TEC2017-87861-R contract. The Research leading to these results has received funding from the European Union Seventh Framework Programme (FP7/2013-2017) under the grant agreement n◦ 312463, FixO3, through the TNA project FISHAUT (grant agreement n◦ FC-01) for accessing the OBSEA data ; Peer Reviewed