The Red Sea Simulator: A high‐precision climate change mesocosm with automated monitoring for the long‐term study of coral reef organisms

Abstract

Experimental systems that enable the controlled perturbation of environmental parameters toward future scenarios are in high demand and becoming increasingly advanced. Herein, we describe the design and assess the performance of a large‐scale, flow‐through, mesocosm system. Located in the northern Gulf of Aqaba, the Red Sea simulator (RSS) was constructed in order to expose local coral reef organisms to future ocean scenarios. Seawater temperature and pH are typically set to a delta from incoming seawater readings and thus follow the diel range. This is achieved through automated monitoring (sensor‐carrying robot) and feedback system and a remote‐controlled user interface. Up to six different temperatures and four pH scenarios can be concomitantly operated in a total of 80 experimental aquaria. In addition, the RSS currently facilitates the manipulation of light intensity, light spectra, nutrient concentration, flow, and feeding regime. Monitoring data show that the system performs well; meeting the user‐defined environmental settings. A variety of reef organisms have been housed in the system for several months. Brooding reef building and soft coral species maintained in the simulator for many months have released planulae in synchrony with field colonies. This system boasts a high degree of replication, potential for multistressor manipulation, typical physiochemical environmental variability, and remotely controlled monitoring and data acquisition. These aspects greatly enhance our ability to make ecologically relevant performance assessments in a changing world.

A new mesocosm system to study the effects of environmental variability on marine species and communities

“…Worldwide, so far only very few mesocosm systems were designed for replicated and longer‐term (> weeks to few months) studies on marine benthic systems in medium to large‐scale experimental units (> 500 L; partly reviewed in Stewart et al ; Wahl et al ). In the tropic and sub‐tropic zones, the SeaSim facility in the Australian Institute for Marine Sciences in Townsville, Queensland, Australia (https://www.aims.gov.au/seasim), the mesocosm facility at the South Australian Research and Development Institute (SARDI) Aquatic Sciences, West Beach, Australia (Falkenberg et al ), a mesocosm system on Hawaii (Jokiel et al ), the CRETACOSMOS at the Hellenic Centre for Marine Research in Greece, the Red Sea Simulator (Bellworthy and Fine ), or the Coral Vivo Project Research Station in Brazil (Duarte et al ), were established ‐ mainly for temperature and pH manipulations in either static or real‐time offset ((Duarte et al ); maintaining field variability) treatment approaches. Some of these systems can also expose organisms or communities to local environmental stressors such as nutrients or contaminants (Duarte et al ), or differing light conditions, salinity shifts, and/or sedimentation (SeaSim, Australia).…”

A method to disentangle and quantify host anabolic turnover in photosymbiotic holobionts with subcellular resolution

“…Three Stylophora pistillata mother colonies were collected in August 2018 at 8 m depth from a coral nursery situated adjacent to the Inter-University Institute for Marine Sciences (Eilat, Israel). The corals were fragmented, mounted on numbered plugs and placed in separate tanks in the Red Sea Simulator (RSS) aquarium system 26 , where they were left for a month to recover from any handling stress incurred and to acclimate to ambient conditions ( Supplementary Fig. 2a).…”

Feeding increases the number of offspring but decreases parental investment of Red Sea coral Stylophora pistillata

“…In order to facilitate planulae collection after 5 months of feeding, colonies were moved to individual experimental aquaria within the Red Sea Simulator (Bellworthy & Fine, 2018) with the same abiotic conditions as the troughs. Water flow into aquaria was maintained and the overflow drain covered with a 200 µm mesh filter to retain released planulae.…”

“…A temperature gradient was chosen to emulate an extension of the full annual thermal range in the GoA. Temperatures of −3, 0, +3, and +6°C relative to ambient (24-25°C) were set in the experimental tanks of the Red Sea Simulator controlled on an individual aquaria basis by titanium heat exchangers (details within Bellworthy & Fine, 2018). These temperatures represented the sea surface temperature in Eilat during February ca.…”