Inter-Research > MEPS > Prepress Abstract

MEPS prepress abstract   -  DOI:

Role of initial energy reserves on stress tolerance thresholds during the early benthic phase in intertidal invertebrates

Shannon R. Mendt*, Louis A. Gosselin

*Corresponding author:

ABSTRACT: Although depleted energy reserves are not a major direct cause of early benthic phase mortality for many species of marine invertebrates, initial energy reserves might nevertheless play a role in early benthic phase mortality through indirect effects on physiological tolerance thresholds, a mechanism that has not been tested. We therefore examined the extent to which energy reserves affect acute tolerance thresholds of early benthic phase individuals of two species (Balanus glandula and Nucella ostrina) to two of the most challenging intertidal stressors: desiccation and high emersion temperature. Levels of energy reserve were controlled by maintaining early benthic phase individuals without food for different durations of time. Individuals in each energy level treatment were then exposed to a range of desiccation periods and emersion temperatures. Energy levels had no effect on tolerance to emersion temperature, but low energy levels did significantly reduce the ability to tolerate desiccation. This suggests the survival of individuals through the early benthic phase is likely dependent on initial energy content through an indirect effect on tolerance to desiccation. Also, habitats experiencing intense desiccation likely impose a selective pressure on intertidal invertebrates favoring the evolution of greater energy reserves at the onset of the early benthic phase. These findings suggest depleted energy reserves at the onset of the early benthic phase can influence early benthic phase mortality through indirect effects by making individuals more vulnerable to environmental stressors. In this way, energy reserves may impact recruitment rates and thus influence population dynamics and intertidal community structure.