title: Swimming against the flow: a mechanism of zooplankton aggregation.
abstract: Zooplankton reside in a constantly flowing environment. However, information about their response to ambient flow has remained elusive, because of the difficulties of following the individual motions of these minute, nearly transparent animals in the ocean. Using a three-dimensional acoustic imaging system, we tracked >375,000 zooplankters at two coastal sites in the Red Sea. Resolution of their motion from that of the water showed that the animals effectively maintained their depth by swimming against upwelling and downwelling currents moving at rates of up to tens of body lengths per second, causing their accumulation at frontal zones. This mechanism explains how oceanic fronts become major feeding grounds for predators and targets for fishermen.
authors.affiliation: Interuniversity Institute for Marine Sciences and the Hebrew University, Eilat, Israel. amatzia@vms.huji.ac.il
authors.forename: Amatzia
authors.initials: A
authors.lastname: Genin
authors.forename: Jules S
authors.initials: JS
authors.lastname: Jaffe
authors.forename: Ruth
authors.initials: R
authors.lastname: Reef
authors.forename: Claudio
authors.initials: C
authors.lastname: Richter
authors.forename: Peter J S
authors.initials: PJ
authors.lastname: Franks
mesh_terms: D000818:Animals; D003463:Cues; D019156:Indian Ocean; D009068:Movement; D011235:Predatory Behavior; D011312:Pressure; D012623:Seawater; D014872:Water Movements; D015048:Zooplankton / Q000502:physiology*