DeepZoo : A cost‐effective and modular sampler for ecological studies in the deep ocean

Abstract Understanding the structure and dynamics of deep‐ocean communities requires effective sampling of pelagic organisms in near‐bottom waters. These dispersive organisms contribute to biodiversity, connectivity and ecosystem recovery. Yet, current sampling methods remain constrained by size, cost, and depth, leaving key questions unanswered in complex and remote habitats such as hydrothermal vents, submarine canyons and the hadal zone. To address these limitations, we developed DeepZoo , a compact and cost‐effective ($15,500) autonomous sampler designed for collecting dispersive zooplankton and benthopelagic juveniles at any ocean depth. Powered by a Blue Robotics T200 thruster and a rechargeable lithium polymer battery, DeepZoo filters water through a user‐selectable mesh‐size net (here, 63 μm) for up to 24 h. Lightweight (6.4 kg in water) and portable, the system can be deployed from a range of stationary and mobile platforms. As proof of concept, DeepZoo was field‐tested during two expeditions: (1) at the 9°50′ N East Pacific Rise hydrothermal vent field alongside a McLane pump, and (2) in the Mar del Plata Submarine Canyon off Argentina. DeepZoo was deployed 12 times (878–3780 m) across four platforms, including landers, the HOV Alvin and the ROV SuBastian . The system recovered fauna from 20 taxonomic groups, including gastropod and bivalve veligers, cold‐water coral planulae and cyprid barnacles, in suitable condition for downstream morphological and molecular identification. Together, these results demonstrate DeepZoo as an accessible tool for sampling zooplankton and benthopelagic biodiversity across complex deep‐ocean habitats using both stationary and mobile deployment platforms. By enabling reliable and comparatively affordable collection, DeepZoo expands sampling capacity into environments previously constrained by cost and logistical barriers, supporting biodiversity and connectivity studies in the deep ocean.