Resource-partitioning and predation impact of a low-latitude myctophid community

摘要: This study, based on data collected during summer 1985 in the eastern Gulf of Mexico, examined degree overlap two prime niche parameters, space and food, 17 most abundant myctophid species which inhabit epipelagic zone at night. Cluster-analyses vertical distribution information diet characteristics revealed that while large groups overlapped (>60%) either distributions or diet, when both parameters were considered together, little interspecific intraspecific (size class) occurred. Our suggest for myctophids trophic competition is reduced through resource-partitioning, although with considerable boundaries. Niche separation presumably result evolution ecosystem maintained presently as “diffuse competition”: effect a combined from all other level. We enables “packing” over 50 calculations indicate predation nightly removes 2% zooplankton biomass. Myctophid selective greatest pressure certain size classes types prey (copepods, ostracods euphausiids). In case copepods, impact larger, more mature stages hence breeding population. It estimated account least one-third daily production removed by micronekton Gulf.