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Food web structure, particularly the relative importance of bottom-up and top-down control of animal abundances, is poorly known for the Earth's largest habitats: the abyssal plains. A unique 15-yr time series of climate, productivity, particulate flux, and abundance of primary consumers (primarily echinoderms) and secondary consumers (fish) was examined to elucidate the response of trophic levels to temporal variation in one another. Towed camera sled deployments in the abyssal northeast Pacific (4100 m water depth) showed that annual mean numbers of the dominant fish genus (Coryphaenoides spp.) more than doubled over the period 1989-2004. Corphaenoides spp. abundance was significantly correlated with total abundance of mobile epibenthic megafauna (echinoderms), with changes in fish abundance lagging behind changes in the echinoderms. Direct correlations between surface climate and fish abundances, and particulate organic carbon (POC) flux and fish abundances, were insignificant, which may be related to the varied response of the potential prey taxa to climate and POC flux. This study provides a rare opportunity to study the long-term dynamics of an unexploited marine fish population and suggests a dominant role for bottom-up control in this system. Key words: benthic megafauna; Coryphaenoides spp.; deep water; marine fish; Pacific Ocean; population dynamics.

New measurements of particulate organic carbon (POC) and the mineralization of this carbon into CO2 in the North Pacific have brought these two previously conflicting processes to within 15% of agreement. This is a vast improvement over previous estimates which had found the POC rate to be as much as 97% short of what is needed to account for the observed levels of CO2 in the benthic community. The new, reconciled figures were obtained by including newly discovered episodic inputs of POC when making the calculations.