Patterns and Variation in Benthic Biodiversity in a Large Marine Ecosystem

Area of Science:

• Marine Ecology
• Biodiversity Science
• Oceanography

Background:

• A well-established inverse relationship exists between latitude and species diversity in many ecosystems.
• Marine biodiversity patterns often deviate from this latitudinal gradient, necessitating further investigation into contributing factors.
• Understanding these deviations is crucial for comprehending large-scale diversity patterns.

Purpose of the Study:

• To investigate benthic marine faunal biodiversity patterns off the US West Coast.
• To determine if marine biodiversity follows a strict latitudinal gradient and how this varies with depth, substrate, and time.
• To assess if coast-wide biodiversity patterns are consistent at regional scales.

Main Methods:

• Utilized an eight-year public monitoring dataset of continental shelf and slope habitats.
• Analyzed biodiversity patterns across latitude, depth (55-1280 m), benthic substrates, and temporal scales.
• Subdivided the study area into three regions to compare coast-wide and regional biodiversity patterns.

Main Results:

• Complex biodiversity patterns were observed, varying by taxonomic group and scale.
• Marine biodiversity was not consistently highest at low latitudes; invertebrate richness and diversity increased with latitude and depth.
• Fish richness increased with latitude and showed a hump-shaped relationship with depth, while regional analyses revealed significant relationships between diversity and environmental factors.

Conclusions:

• Latitude, depth, substrate, and year are key factors shaping marine fish and invertebrate diversity.
• Coast-wide biodiversity patterns can obscure significant regional-scale relationships.
• Deep-water soft-substrate benthic ecosystems exhibit complex diversity patterns influenced by multiple environmental variables.