Acclimation in intertidal animals reduces potential pathogen load and increases survival following a heatwave

Elliot Scanes; Nachshon Siboni; Brendon Rees; Justin R Seymour

doi:10.1016/j.isci.2023.106813

Acclimation in intertidal animals reduces potential pathogen load and increases survival following a heatwave

iScience. 2023 May 4;26(6):106813. doi: 10.1016/j.isci.2023.106813. eCollection 2023 Jun 16.

Authors

Elliot Scanes^{1

2}, Nachshon Siboni¹, Brendon Rees¹, Justin R Seymour¹

Affiliations

¹ Climate Change Cluster, University of Technology Sydney, Ultimo, NSW 2007, Australia.
² Sydney Institute of Marine Science, Mosman, NSW 2088, Australia.

Abstract

Intertidal animals can experience intense heat during a heatwave, leading to mortality. The causes of death for intertidal animals following heatwaves have often been attributed to a breakdown in physiological processes. This, however, contrasts with research in other animals where heatwave mortality is attributed to existing or opportunistic diseases. We acclimated intertidal oysters to four treatment levels, including an antibiotic treatment, and then exposed all treatments to a 50°C heatwave for 2 h, replicating what can be experienced on Australian shorelines. We found that both acclimation and antibiotics increased survival and reduced the presence of potential pathogens. Non-acclimated oysters had a significant shift in their microbiome, with increasing abundances of bacteria from the Vibrio genera, including known potential pathogens. Our results demonstrate that bacterial infection plays a pivotal role in post-heatwave mortality. We anticipate these findings to inform the management of aquaculture and intertidal habitats as climate change intensifies.

Keywords: Biological sciences; Global change; Marine organism.