What shells remember: Marine Invertebrate responses to environmental change

Presented by Bailey Brooker

Honours Student, James Cook University

Supervisors: A/Prof Sue-Ann Watson (JCU), Dr Michela Mitchell (JCU)

Intensifying simultaneous stressors on coral reefs demand long-term, multi-factor data, yet such data sets are scarce. Natural history museum collections are a valuable resource for global climate change biology, providing centuries of evidence for pre- and post-industrial impacts. Biological specimens are a snapshot of the combined lifetime effects of all environmental variables, expressing adaptation over time and space. We analysed morphometric changes in calcified functional structures like shells, apertures, carapaces, and chelae in 16 gastropod and crustacean species (1900+ specimens) held at the Australian Museum collected over the past 150 years.

Data to date shows trend changes in morphologic traits such as body size and calcification correlating with increasing temperature, ocean acidification, decreasing carbonate saturation state, and other ocean dynamics. Assessing and predicting changes in predatory, defensive, and environmentally reactive traits explores reef-wide resilience and informs the health, and management needs, of future coral reef communities under accelerating climate change.