title: Growth of a deep-water, predatory fish is influenced by the productivity of a boundary current system.
abstract: The effects of climate change on predatory fishes in deep shelf areas are difficult to predict because complex processes may govern food availability and temperature at depth. We characterised the net impact of recent environmental changes on hapuku (Polyprion oxygeneios), an apex predator found in continental slope habitats (>200 m depth) by using dendrochronology techniques to develop a multi-decadal record of growth from otoliths. Fish were sampled off temperate south-western Australia, a region strongly influenced by the Leeuwin Current, a poleward-flowing, eastern boundary current. The common variance among individual growth records was relatively low (3.4%), but the otolith chronology was positively correlated (r = 0.61, p < 0.02) with sea level at Fremantle, a proxy for the strength of the Leeuwin Current. The Leeuwin Current influences the primary productivity of shelf ecosystems, with a strong current favouring growth in hapuku. Leeuwin Current strength is predicted to decline under climate change models and this study provides evidence that associated productivity changes may flow through to higher trophic levels even in deep water habitats.
authors.affiliation: School of Animal Biology, University of Western Australia, Crawley WA, Australia.
authors.forename: Hoang Minh
authors.initials: HM
authors.lastname: Nguyen
authors.affiliation: 1] Centre for Marine Futures, Oceans Institute, University of Western Australia, Crawley WA, Australia [2] Museum of Paleontology, University of Michigan, Ann Arbor MI, USA.
authors.forename: Adam N
authors.initials: AN
authors.lastname: Rountrey
authors.affiliation: 1] School of Animal Biology, University of Western Australia, Crawley WA, Australia [2] Centre for Marine Futures, Oceans Institute, University of Western Australia, Crawley WA, Australia.
authors.forename: Jessica J
authors.initials: JJ
authors.lastname: Meeuwig
authors.affiliation: Centre for Fish and Fisheries Research, School of Veterinary and Life Sciences, Murdoch University, Murdoch WA, Australia.
authors.forename: Peter G
authors.initials: PG
authors.lastname: Coulson
authors.affiliation: CSIRO Oceans &Atmosphere Flagship, Underwood Avenue, Floreat, WA 6014, Australia.
authors.forename: Ming
authors.initials: M
authors.lastname: Feng
authors.affiliation: Western Australian Fisheries and Marine Research Laboratories, Department of Fisheries, Government of Western AustraliaPO Box 20, North Beach, WA 6920, Australia.
authors.forename: Stephen J
authors.initials: SJ
authors.lastname: Newman
authors.affiliation: School of Civil, Environmental and Mining Engineering, University of Western Australia, Crawley WA, Australia.
authors.forename: Anya M
authors.initials: AM
authors.lastname: Waite
authors.affiliation: Western Australian Fisheries and Marine Research Laboratories, Department of Fisheries, Government of Western AustraliaPO Box 20, North Beach, WA 6920, Australia.
authors.forename: Corey B
authors.initials: CB
authors.lastname: Wakefield
authors.affiliation: Australian Institute of Marine Science, Crawley WA, Australia.
authors.forename: Mark G
authors.initials: MG
authors.lastname: Meekan
mesh_terms: D000818:Animals; D017753:Ecosystem; D004777:Environment; D005399:Fishes; D011235:Predatory Behavior