Habitats and fish communities at mesophotic depths in the Mexican Pacific

Aim: Mesophotic ecosystems, found at the limit of light penetration in the ocean, are rich in biodiversity and harbor unique ecological communities. However, they remain among the least studied habitat zones on earth due to high costs and technological limitations. Here, we characterize mesophotic communities in two marine reserves across a range of habitat types, depths, and temperatures using submersible technologies, with the goal of understanding the processes that structure these communities across biogeographic regions.
Location: The Bay of La Paz and the Revillagigedo Archipelago, Mexico.
Taxa: Fish and algal species.
Methods: We used a small and inexpensive Remotely Operated Vehicle (ROV) to conduct roving-swim surveys of major habitat types in depths from 20–100 m. With the resulting binary data of fish species presence, we used generalized linear mixed models and canonical correspondence analysis and to determine whether biogenic habitat, depth, and/or temperature best explain...