Sabellaria wilsoni Lana and Gruet, 1989 on the Brazilian Amazon coast: Fast growth with high mortality, production, and turnover rate

Abstract

Given the enormous ecological importance of sabellariid (Annelida: Sabellariidae) reefs for marine environments, data on the life history traits of these reef builders are essential for understanding ecosystem function. We assessed the functional parameters of a population of Sabellaria wilsoni (Annelida: Sabellariidae) on the Brazilian Amazon coast, where this polychaete builds extensive reef systems. The species had fast growth, a relatively short life span (1.30 years), and a high mortality rate (3.87 year⁻¹). The mean annual biomass (58 g AFDM m⁻²) and production (233 g AFDM m⁻² year⁻¹) were very high and resulted in a high production-to-biomass ratio (P/B ratio: 4.02 year⁻¹). The months with the highest productivity were those with the greatest reef coverage and density of worms, which coincided with the periods of reef growth. The high P/B ratio indicates the rapid replacement of biomass in this tropical population. These data support the hypothesis that S. wilsoni is an r-strategist, which is favored by the elevated temperatures and abundance of feeding resources and grains (for tube building) found on the Amazon coast. The present study is the first to produce systematic data on the population dynamics and production of a sabellariid species in the Western Atlantic Ocean. These data provide a baseline for understanding how shallow-water trophic webs function, as well as for monitoring these coastal habitats in the tropics.