title: Reproductive efficiency of a Mediterranean endemic zooxanthellate coral decreases with increasing temperature along a wide latitudinal gradient.
abstract: Investments at the organismal level towards reproduction and growth are often used as indicators of health. Understanding how such energy allocation varies with environmental conditions may, therefore, aid in predicting possible responses to global climatic change in the near future. For example, variations in seawater temperature may alter the physiological functioning, behavior, reproductive output and demographic traits (e.g., productivity) of marine organisms, leading to shifts in the structure, spatial range, and abundance of populations. This study investigated variations in reproductive output associated with local seawater temperature along a wide latitudinal gradient on the western Italian coast, in the zooxanthellate Mediterranean coral, Balanophyllia europaea. Reproductive potential varied significantly among sites, where B. europaea individuals from the warmest site experienced loss of oocytes during gametogenesis. Most of the early oocytes from warmest sites did not reach maturity, possibly due to inhibition of metabolic processes at high temperatures, causing B. europaea to reabsorb the oocytes and utilize them as energy for other vital functions. In a progressively warming Mediterranean, the efficiency of the energy invested in reproduction could be considerably reduced in this species, thereby affecting vital processes. Given the projected increase in seawater temperature as a consequence of global climate change, the present study adds evidence to the threats posed by high temperatures to the survival of B. europaea in the next decades.
authors.affiliation: Marine Science Group, Department of Biological, Geological and Environmental Sciences, Section of Biology, Alma Mater Studiorum - University of Bologna, Bologna, Italy, European Union.
authors.forename: Valentina
authors.initials: V
authors.lastname: Airi
authors.affiliation: Marine Science Group, Department of Biological, Geological and Environmental Sciences, Section of Biology, Alma Mater Studiorum - University of Bologna, Bologna, Italy, European Union.
authors.forename: Francesca
authors.initials: F
authors.lastname: Gizzi
authors.affiliation: Department of Chemistry "G. Ciamician," Alma Mater Studiorum - University of Bologna, Bologna, Italy, European Union.
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Falini
authors.affiliation: The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan, Israel.
authors.forename: Oren
authors.initials: O
authors.lastname: Levy
authors.affiliation: The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan, Israel.
authors.forename: Zvy
authors.initials: Z
authors.lastname: Dubinsky
authors.affiliation: Marine Science Group, Department of Biological, Geological and Environmental Sciences, Section of Biology, Alma Mater Studiorum - University of Bologna, Bologna, Italy, European Union.
authors.forename: Stefano
authors.initials: S
authors.lastname: Goffredo
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D037421:Anthozoa; D048429:Cell Size; D057231:Climate Change; D017753:Ecosystem; D004777:Environment; D005843:Geography; D005854:Germ Cells / Q000166:cytology; D019083:Mediterranean Region; D009865:Oocytes / Q000166:cytology; D012098:Reproduction; D013696:Temperature