Thermal preference, tolerance, and thermal aerobic scope in clownfish Amphiprion ocellaris (Cuvier, 1830) predict its aquaculture potential across tropical regions

Abstract

The clownfish Amphiprion ocellaris is widely distributed in the coral reef ecosystems of tropical and subtropical regions of the West Indo Pacific, an area that hosts economically valuable species, and, thus, a suitable candidate for warm water aquaculture. This study determined the preferred temperature, critical threshold limits, represented by critical thermal maximum and critical thermal minimum, thermal window width, and aerobic metabolic scope of A. ocellaris clownfish acclimated to 20, 23, 26, 29, 32, and 35°C. A positive response (P \ 0.05) occurred when the preferred temperature significantly increased with increasing acclimation temperature. The preferred temperature obtained graphically was 30.0°C. Acclimation temperature significantly affected the thermal tolerance which increased with acclimation temperature. The thermal window calculated for A. ocellaris was 301.5°C 2 . The thermal metabolic scope obtained in animals acclimated at the interval from 23 to 32°C (P [ 0.05) had a mean value of 4240.8 mg O 2 h -1 kg -1 w.w., revealing that A. ocellaris is a eurythermal species with a range of optimal physiological performance that closely matches the environmental conditions where it can be farmed. Therefore, the highest value of the thermal aerobic scopes corresponded to the intervals of the preferred temperature obtained for A. ocellaris. These results may partially explain their worldwide distribution pattern, as well as their aquaculture potential in tropical regions.

Evolution, Development and Ecology of Anemonefishes

“…The sub-tropical wideband anemonefish, Amphirion latezonatus, exhibited a maximum specific growth rate between 22-23°C, which is consistent with the sub-tropical distribution of this species (Rushworth et al 2011). For A. ocellaris, the preferred temperature ranged from approximately 27-32°C depending on the holding temperate of the fish (from 20-35°C), while aerobic metabolic performance was maintained across 23-32°C (Velasco- Blanco et al 2019), consistent with the tropical distribution of this species. Overall, this work suggests that juvenile anemonefishes may be relatively robust to ocean warming, with no performance declines up to 32°C.…”

“…However, these estimates of thermal sensitivity are far lower than estimates that would be extrapolated from critical maximum limits, with the critical maximum for A. ocellaris 3. 7-8.1°C warmer (35.7-40.1°C;Paschke et al 2018;Velasco-Blanco et al 2019).…”

Synergistic Effects of Ocean Warming and Cyanide Poisoning in an Ornamental Tropical Reef Fish

“…Physiological condition and species-specific metabolic rates (resting, routine, or maximum metabolic rates, Ikeda, 2016) may be determinant factors explaining interspecific variation in survival/mortality, as these determine uptake and elimination rates of contaminants (Mason, 2002). For instance, juvenile clownfish have a resting metabolic rate of approximately 1 mg O 2 h −1 g WW −1 , while their maximum metabolic rate can reach over 5 mg O 2 h −1 g WW −1 (23-32 • C) (Paschke et al, 2018;Velasco-Blanco et al, 2019). However, Chromis species can have resting metabolic rates in the order of 0.2-0.5 mg O 2 h −1 g WW −1 and maximum metabolic rates between 1.5 and 2 mg O 2 h −1 g WW −1 (Johansen and Jones, 2011;Nadler et al, 2016).…”

Long‐term mild hypoxia does not reduce thermal tolerance or performance of the freshwater prawn Macrobrachium tenellum

“…Understanding the ability of prawns to tolerate hypoxia is therefore crucial, especially for species of ecological and commercial importance. Hypoxia can be particularly acute in tropical zones during the dry season and warmer months, when the decomposition of organic matter consumes DO and the density-driven stratification of the water column isolates bottom water from oxygen-rich surface water (Bishop et al, 2006;Tyler et al, 2009); this situation is probably worse in polluted waters. The effects of short-term hypoxia (6 days) were evaluated through haemolymph physiology in Macrobrachium rosenbergii (De Man, 1879), a relative of M. tenellum, in an attempt to gather useful information on the proper management of its aquaculture environment (Cheng et al, 2003).…”

“…For these reasons, CT Max has been recognized as an excellent index and standardized method to evaluate the thermal limits and physiology of aquatic organisms exposed to environmental stressors (Madeira et al, 2012; Nikinmaa, 2013; Terblanche et al, 2011; Vinagre et al, 2014). The most frequently observed responses following a temperature increase of 1°C·min −1 were, in order: greater locomotory activity in attempt to escape, loss of equilibrium, onset of muscle spasms and death a few minutes later (Hutchison & Maness, 1979; Lutterschmidt & Hutchison, 1997b; Velasco‐Blanco et al, 2019). When all those concepts are used to define optimal conditions for aquatic species with aquaculture potential, such as M. tenellum , this knowledge acquires special relevance (Chen et al, 2015); it helps define the limits that should be considered when the particular prawn is held under culture conditions, helping thus design the best culture strategy.…”