Confronting uncertainty in the contribution of mesopelagic fishes to the biological carbon pump

Abstract

The framework of ecosystem services is one way of understanding and describing the beneficial processes and functions that humans receive from the natural world. Many ecosystem services come from the oceans, such as benefits we receive from marine fisheries and the role the oceans play in regulating global climate and mitigating climate change. Some of the world's most abundant fishes—mesopelagic fishes like myctophids—contribute to each of the major categories of ecosystem services including provisioning services, regulating services, cultural services, and supporting services. This dissertation focuses on further quantifying their role in regulating services, specifically carbon transport and sequestration. Findings related to key sources of uncertainty in estimating fish-mediated carbon transport can be used in prioritizing research efforts to further describe this ecosystem service, while minimum and maximum estimates of mesopelagic fish carbon transport further our understanding of this ecosystem service despite uncertainty. Quantitative findings from these chapters may be used in the future to inform decision-making processes that evaluate potential trade-offs among ecosystem services associated with mesopelagic fishes.