Predator-guided sampling reveals biotic structure in the bathypelagic.

Area of Science:

• Marine Ecology
• Deep-Sea Biology
• Oceanography

Background:

• Deep-diving predators rely on specific prey distributions.
• Understanding deep-sea habitats is crucial for marine ecosystem studies.
• Previous research often assumed uniform deep-water environments.

Purpose of the Study:

• To investigate the spatial variability of prey for deep-diving predators.
• To analyze deep-sea prey characteristics and distribution patterns.
• To challenge the notion of a uniform deep-water habitat.

Main Methods:

• Utilized fisheries echosounders on a surface ship and a deep-diving autonomous vehicle.
• Collected fine-scale measurements of biota from the surface to 1,200 m depth.
• Examined spatial variability in prey size, composition, biomass, and organization.

Main Results:

• Significant spatial variability in biota was observed across all scales.
• Prey characteristics differed notably between deep-sea regions, not mirroring surface layers.
• Deep-water heterogeneity was evident from 10 m to 50 km scales.

Conclusions:

• Deep-sea habitats are not uniform but spatially heterogeneous.
• This heterogeneity significantly impacts predator-prey interactions and energy transfer.
• Findings reshape our understanding of deep-sea ecological processes and connectivity.