Benthic scavenger assemblages along a depth gradient: megafauna-macrofauna divergence.

Area of Science:

• Marine Ecology
• Benthic Ecology
• Biodiversity Studies

Background:

• Benthic scavengers are crucial for nutrient cycling in soft-bottom ecosystems.
• Depth-related patterns of scavenger communities are poorly understood.

Purpose of the Study:

• To characterize depth-related patterns of benthic scavenger assemblages.
• To assess the distribution and ecology of megafauna and macrofauna scavengers along a soft-bottom depth gradient.

Main Methods:

• Baited traps were deployed at 30, 50, and 70m depths in Viana do Castelo, NW Iberian Peninsula.
• Megafauna and macrofauna communities were sampled to analyze depth-related variations.

Main Results:

• Megafaunal assemblages significantly differed with depth, with abundance and biomass metrics revealing distinct patterns.
• Macrofaunal assemblages showed no significant depth variation, dominated by amphipods and isopods.
• Tritia reticulata abundance characterized mid-depths, while Polybius henslowii biomass dominated shallow sites.

Conclusions:

• Depth influences megafaunal scavenger communities, but not macrofaunal ones in this region.
• Abundance and biomass metrics provide complementary insights into faunal responses to environmental gradients.
• A depth-resolved baseline for soft-bottom scavenger biodiversity in North Portugal was established.