Publication Date:
2017-01-20
Description:
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.
Repository Name:
EPIC Alfred Wegener Institut
Type:
Article
,
isiRev
Format:
application/pdf
