National marine sanctuary offices and visitor centers closed to the public; waters remain open

NOAA's national marine sanctuary offices and visitor centers are currently closed to the public, and in accordance with Executive Order 13991 - Protecting the Federal Workforce and Requiring Mask Wearing, all individuals in NOAA-managed areas are required to follow Centers for Disease Control and Prevention (CDC) guidance on mask-wearing and maintaining social distances. Sanctuary waters remain open for responsible use in accordance with CDC guidance, U.S. Coast Guard requirements, and local regulations. More information on the response from NOAA's Office of National Marine Sanctuaries can be found on

Skip to main content
Monterey Bay National Marine Sanctuary National Marine Sanctuaries Home Page National Oceanic and Atmospheric Administration Home Page

Research Technical Report

The Distribution of Demersal Fishes Over Heterogeneous Seafloor Habitats: An Application of Landscape Ecology to Video Imagery Collected in a Central California State Marine Conservation Area

Knight, A. (Fall 2011)

M.S. Thesis, California State University Monterey Bay, 63pp.


Using landscape ecology approaches, this study investigated the importance of structural patterning in the seafloor landscape and the scales at which demersal fishes associate with different habitats. The following document describes the project in three parts: 1) The circumstances surrounding the management of the study site and the methodological approaches used; 2) The analytical framework and results; 3) Potential applications of these results in management.

By describing the landscapes across which demersal fish are distributed at the Piedras Blancas State Marine Conservation Area (PBSMCA), within the Monterey Bay National Marine Sanctuary, we evaluated fish-habitat associations in the context of other central California deepwater studies. Quantifying and monitoring the distribution of fishes over the habitats at this site is critical to understanding how this marine protected area (MPA) may function as a conservation measure.

Imagery surveys are ideal for collecting data on seafloor habitats and observing fishes in these habitats; these data are becoming an increasingly important contribution to marine conservation management. We examined imagery collected at the PBSMCA with a towed camera system. Surveys were conducted in 2007 and 2008 in water depths ranging from 30- 120 m. Video imagery gathered with the sled was viewed as a set of non-overlapping video quadrats (frames). We compared generalized linear models to estimate the probability of response (detection) of selected demersal fish groups to a number of habitat variables, assuming a uniform probability of detection.

Results suggested that, for all fish groupings, there is evidence that seafloor substrate plays a very strong role in determining distributions. Depth also played an important role, while biogenic structure and soft-sediment bedforms were rarely of importance to the distributions. Our results are consistent for the most part with fish distribution studies conducted at other sites within the central California region.

These results highlight the importance of using imagery to collect monitoring data about marine landscapes. Use of a simple, low-cost camera system enabled us to address complex ecological questions about demersal fish-habitat associations across a heterogeneous landscape and provided useful results in the form of baseline data to MPA managers and site characterization to the Monterey Bay National Marine Sanctuary.