Body size mediated effects of multiple abiotic stressors on the growth and social behaviour of an estuarine fish, Australian Bass (Macquaria novemaculeata)

Abstract

. (2015). Body size mediated effects of multiple abiotic stressors on the growth and social behaviour of an estuarine fish, Australian Bass (Macquaria novemaculeata). Environmental Biology of Fishes, 99 (1), 95-104. Body size mediated effects of multiple abiotic stressors on the growth and social behaviour of an estuarine fish, Australian Bass (Macquaria novemaculeata) AbstractAnthropogenic climate change is expected to result in dramatic shifts in the abiotic conditions within estuaries, including an elevation of temperature and salinity levels. Even so, few studies have addressed the impacts of multiple abiotic stressors on the behaviour and life history of key estuarine species, such as those of biological and commercial importance. Here we used a cross-factored experimental design to tease apart the effects of temperature and salinity on intraspecific aggression and growth rates of a native estuarine fish species, the Australian bass (Macquaria novemaculeata). Juvenile bass were exposed to one of four treatment conditions: 1) baseline temperature and salinity, 2) elevated temperature, 3) elevated salinity, and 4) elevated temperature and salinity. Elevated salinity increased rates of aggression, and elevated temperature decreased rates of growth, although the effects of both factors were mediated by the body size of individual bass. These results therefore highlight complex and variable effects of abiotic stressors and body size, emphasising the importance of considering individual-level attributes when evaluating the impacts of climate change on estuarine fishes. BODY SIZE MEDIATED EFFECTS OF MULTIPLE ABIOTIC STRESSORS ON THE GROWTH AND SOCIAL BEHAVIOUR OF AN ESTUARINE FISH, AUSTRALIAN BASS (MACQUARIA NOVEMACULEATA) Authors ABSRACTAnthropogenic climate change is expected to result in dramatic shifts in the abiotic conditions within estuaries, including an elevation of temperature and salinity levels. Even so, few studies have addressed the impacts of multiple abiotic stressors on the behaviour and life history of key estuarine species, such as those of biological and commercial importance. Here we used a cross-factored experimental design to tease apart the effects of temperature and salinity on intraspecific aggression and growth rates of a native estuarine fish species, the Australian bass (Macquaria novemaculeata). Juvenile bass were exposed to one of four treatment conditions: 1) baseline temperature and salinity, 2) elevated temperature, 3) elevated salinity, and 4) elevated temperature and salinity. Elevated salinity increased rates of aggression, and elevated temperature decreased rates of growth, although the effects of both factors were mediated by the body size of individual bass. These results therefore highlight complex and variable effects of abiotic stressors and body size, emphasising the importance of considering individual-level attributes when evaluating the impacts of climate change on estuarine fishes.

Response of estuarine fishes to elevated temperatures within temperate Australia: Implications of climate change on fish growth and foraging performance

“…We found no significant association between foraging and growth, an unexpected finding since individuals that exhibit greater feeding rates and aggression are usually also those that grow quicker and larger, due to a reduced perceived risk of predation, increased metabolic demands, and increased competitive ability and processing capacities (Grigaltchik et al, 2012;O'Mara and Wong, 2016;Rodriguez-Dominguez et al, 2019). A lack of relationship may have been because of inter-individual behavioural variation, relatively low sample numbers or because of laboratory conditions, most likely the high food availability (Killen et al, 2011;Liu and Fu, 2017).…”

The effect of density on aggression between a highly invasive and native fish

“…Only one person (LKL) observed the fish to avoid potential issues with observer bias. Each focal individual was observed for 10 min during which time the number of aggressive (approaches, chases and nips) behavioural interactions between other individuals was recorded (Flood & Wong, ; Matthews & Wong, ; O'Mara & Wong, ). To account for diurnal variation in behaviour, the same fish were observed once in the morning (0900–1200) and once in the afternoon (1300–1600).…”

Exploring the Research Landscape of Endemic Catadromous Fishes: A Comprehensive Bibliometric Study and PRISMA Review

“…Research on climate change impacts has primarily been on A. dieffenbachii, M. novemaculeata, and P. colonorum. These studies have examined the effect of climate warming on the recruitment and growth of the population productivity of P. colonorum [81], elevated salinity and temperature impacts on M. novemaculeata [82], global warming effects on the predator-prey interactions of M. novemaculeata, and the implications of increased water temperature on glass eels' recruitment of A. dieffenbachii [83]. Regarding future themes, it is crucial to address research gaps in life-history information and conservation strategies for the lesser-studied endemic catadromous species, including those in developing countries.…”