Juvenile Gadoid Distributions Are Driven by Patch Boundaries and Habitat Combinations

Area of Science:

• Marine ecology
• Seascape ecology
• Fisheries science

Background:

• Juvenile fish nursery areas require appropriate spatial scale and habitat understanding.
• Seascape ecology provides insights into habitat type combinations and arrangements influencing species distribution.

Purpose of the Study:

• Investigate seascape ecology and species co-occurrence patterns on juvenile gadoid distribution.
• Determine seascape drivers for Atlantic cod, haddock, and whiting.
• Account for inter-species interactions as latent variables.

Main Methods:

• Utilized 757 stereo baited remote underwater video (SBRUV) deployments from 2021-2023.
• Collected relative abundance data across two Scottish sea lochs and adjacent bays.
• Employed a joint species distribution model to analyze seascape drivers and co-occurrence patterns.

Main Results:

• Atlantic cod, haddock, and whiting distributions were influenced by distinct ecological factors with limited overlap.
• Atlantic cod and haddock favored diverse habitats, while whiting preferred lower habitat diversity.
• Higher abundance near habitat patch boundaries indicated critical edge effects for nursery habitats.

Conclusions:

• Seascape structure significantly influences juvenile gadoid distribution and nursery habitat suitability.
• Species co-occurrence patterns were similar despite distinct environmental drivers, suggesting shared ecological roles or responses to unrecorded variables.
• Understanding seascape influences is vital for effective management of juvenile fish populations at relevant spatial scales.