Key Questions for Research and Conservation of Mesophotic Coral Ecosystems and Temperate Mesophotic Ecosystems

Abstract

Mesophotic coral ecosystems (MCEs) and temperate mesophotic ecosystems (TMEs) have received increasing research attention during the last decade as many new and improved methods and technologies have become more accessible to explore deeper parts of the ocean. However, large voids in knowledge remain in our scientific understanding, limiting our ability to make scientifically based decisions for conservation and management of these ecosystems. Here, we present a list of key research and con-servation questions to enhance progress in the field. Questions were generated following an initial open call to MCE and TME experts, representing a range of career levels, interests, organizations (including academia, governmental, and nongovernmental), and geographic locations. Questions were refined and grouped into eight broad themes: (1) Distribution, (2) Environmental and Physical Processes, (3) Biodiversity and Community Structure, (4) Ecological Processes, (5) Connectivity, (6) Physiology, (7) Threats, and (8) Management and Policy.

A generalized light‐driven model of community transitions along coral reef depth gradients

“…It will be part of the iterative nature of science for this model to eventually be superseded by a more nuanced method for identifying MCEs, as we hope this tool allows the field to move on from fixed depth limits. There are clearly other processes that would provide valuable extensions, once characterized by future studies (Turner et al., 2019). Substrate availability, maximum depth of a site, temperatures, and other uncaptured processes could all contribute to deviations from model predictions in the field.…”

“…This highlights how species physiology may need to be linked to community models through an understanding of the light field. Linking mesophotic taxa to abiotic conditions is, therefore, a research priority for the field (Costa et al., 2015; Turner et al., 2019). When doing this, it is important to remember that depth range alone is a poor descriptor of a species’ niche.…”

Mesophotic.org: a repository for scientific information on mesophotic ecosystems

“…According to the NOAA definition, ‘mesophotic coral ecosystems (MCEs) are characterized by the presence of light-dependent corals and associated communities typically found at depths ranging from 30 to 40 m and extending to over 150 m in tropical and subtropical regions’ (5, 7). Following that, the term ‘mesophotic’ started to be more broadly used to refer to benthic habitats within the depth zone of 30–150 m depth, including in temperate waters (8, 9) where communities at those depths are now characterized as ‘temperate mesophotic ecosystems’ (10).…”

“…Considering the rapid decline of shallow reefs due to the effects of climate change (18, 19), MCEs have become a common interest among not only the scientific community but also governmental organizations and non-profit groups (10, 20). There is an emerging consensus that despite their potential role as refuges, MCEs are not immune to disturbance and instead are vulnerable in their own right (16, 21, 22).…”

Editorial: Coral Reefs in the Anthropocene – Reflecting on 20 Years of Reef Conservation UK

“…In addition to the papers in this Research Topic, ECRS provided a platform for many other coral reef-related events and outputs. For example, the symposium hosted the European launch of the 2018 International Year of the Reef on the 13th December 2017, and several of the workshops produced published outputs (e.g., Turner et al, 2019).…”