BES Grant Report: Susceptibility of black bream to climate warming: Considerations of body size and populations.
Abstract
This study aimed to examine whether intraspecific variation in body mass and populations impacts upper thermal limits in black bream (Acanthopagrus butcheri), an estuarine fish. It tested the hypothesis that thermal tolerance would decrease with increasing body mass and vary across populations correlating with latitudinal temperature ranges. Fish were collected from 4 estuaries along the West Australian coastline, and their critical thermal maximum (CTmax) was measured. Results showed no significant relationship between body mass and CTmax, but CTmax varied among populations, with the southern population displaying slightly lower thermal tolerance. The study highlights the importance of considering intraspecific variation in thermal limits for conservation efforts.