Elevated species diversity in abyssal gastropods off Newfoundland: the potential role of food supply

Abstract

We compare species diversity and composition in a large sample of deep-sea gastropods collected off Newfoundland and the Grand Banks (4,400 m) to samples from the continental rise (3,806-3,834 m) and abyssal plain (4,680-4,970 m) south of New England. The sample from Newfoundland shares half its species with the fauna found south of New England, but is distinguished compositionally from both continental rise and abyssal communities. Species diversity off Newfoundland is similar to diversity at continental rise depths, but significantly higher than at abyssal depths south of New England. Elevated abyssal diversity off Newfoundland is associated with higher surface production and rates of particulate organic carbon flux to the seafloor, suggesting that food supply potentially plays an important role in regulating diversity at great depths.