Regulation of population size, growth, and production of a deposit-feeding bivalve: A long-term field study of three deep-water populations off the swedish west coast

摘要: Abstract Dynamics in three deep-water populations, one northern and southern at 100 m 300 m, of the surface deposit-feeding bivalve Abra nitida (Muller) were studied during period 1970–1980. Recruitment, growth terms length, mortality, production biomass assessed by means length frequency distribution analysis quantitative samples. Recruitment success different years was negatively correlated with adult density/population two localities, deep. The mortality 0-group positively size/density itself. Mortality among adults considerably higher for population data are presented indicating a negative relationship between predatory snail Natica. average rates compared which is attributed to better food supply rather than temperature. Growth density/biomass stations where dominated. Production (shells included) calculated 9 consecutive yr station, 4 m. P ranged from 9.94 37.85 g dry wt· m−2 /sd yr−1 : B ratios 0.54 1.46 former site, corresponding values latter site 0.57–2.62 0.46–2.5. on high “deep” community. It concluded that normally factors regulating populations operated bottom planktonic phase. results strongly indicated resource limitation factor prime importance deepest (300 m) population, primarily acting through adult-larval interactions, while predation probably plays greater role At may occasionally reach an density 2000 ind. · m−2, both affected dynamics species. Reasons “volatility” shown species discussed, whereby good competitive ability together susceptibility considered be important. findings demonstrate density-dependent these depositfeeding populations.