# Physiology and Survival of Intertidal Calcifiers in Two Contrasting Upwelling Systems

## TL;DR

This study examines how two types of sea mollusks respond to different ocean conditions, finding that survival and metabolism vary with upwelling patterns.

## Contribution

The study combines field and lab methods to assess survival and physiology of intertidal mollusks in contrasting upwelling systems.

## Key findings

- Heart rate does not differ between populations of both species.
- S. zebrina in seasonal upwelling has higher metabolism.
- Survival is significantly higher in semi-permanent upwelling locations.

## Abstract

Climate change alters the oceans' temperature, pH, and oxygen concentration. These changes are expected to increase globally over the coming decades, affecting a wide range of marine organisms. Coastal upwelling zones, characterized by their high environmental variability, serve as ideal natural laboratories to study the potential impacts on marine organisms and ecosystems of temperature change, acidification, and ocean deoxygenation. The estimation of survival using capture‐mark‐recapture (CMR) data has been commonly applied to vertebrates, and to date, very few studies have been done on marine invertebrate organisms. In this study, we combined field CMR data and laboratory measurements to assess the physiological responses (metabolic rate and heart rate) and survival probability of individuals in two populations of intertidal mollusks, Chiton granosus and Scurria zebrina, in contrasting upwelling environments (i.e., semi‐permanent vs. seasonal). We found that (1) there are no differences between the two studied populations for heart rate in both species, (2) the
S. zebrina
population subjected to seasonal upwelling has a higher metabolism, (3) there are no differences in the calcification rate between the two studied populations of both species, and (4) survival is significantly higher in the semi‐permanent upwelling location for both species. Our findings highlight species‐specific responses to contrasting upwelling regimes, suggesting that phenotypic plasticity and survival differences may influence resilience under ongoing climate change.

This study evaluates the physiological responses and survival of two intertidal mollusk species, Chiton granosus and Scurria zebrina, across contrasting upwelling environments. We found that metabolic rates and survival differ between populations exposed to seasonal versus semi‐permanent upwelling. These findings highlight the importance of phenotypic plasticity and environmental variability in shaping species' resilience to climate change in coastal ecosystems.