PDF Lara_Neira_Zoop...pdf | Request a copy Full text restricted

Abstract

We examined the spatio-temporal synchronicity between zooplankton biomass and larval fish concentrations within a highly flushed system in northern Tasmania, Australia, combining the data from nets and acoustic methods obtained between October 2001 and November 2002. Zooplankton and larval fish data from nets were analysed in terms of water temperature, salinity and freshwater flow, while backscatter strength from an Acoustic Doppler Current Profiler (ADCP) was employed to complement zooplankton–net data and identify the likely areas of high secondary productivity. Zooplankton and fishes varied significantly across months, peaking simultaneously during late spring (November) at an average temperature of ~15oC. Maximum zooplankton (20.5 mgC/m3) and fishes (874 larvae/100 m3)were recorded within mesohaline (5–17) and polyhaline (18–29) zones, respectively, also in spring. Peaks in zooplankton and larval fish occurred a month after peak freshwater flow, with temperature explaining variability better than did flow or salinity. The coupling of spring peaks in zooplankton biomass and larval fish implies that estuary-spawning fishes may have a fixed spawning period timed to increasing temperatures to ensure a match with abundant microplankton food supply. Backscatter strength complemented zooplankton biomass from nets, and could arguably be used as a proxy for zooplankton abundance
even within “noisy” estuarine systems.

Item Type:	Article
Authors/Creators:	Lara-Lopez, A and Neira, FJ
Keywords:	Zooplankton biomass, larval fishes, ADCP, backscatter strength, estuarine processes, Tamar Estuary, Tasmania, Australia
Journal or Publication Title:	Journal of Plankton Research
ISSN:	0142-7873
DOI / ID Number:	https://doi.org/10.1093/plankt/fbn063
Additional Information:	The definitive publisher-authenticated version is available online at: www.oxfordjournals.org
Item Statistics:	View statistics for this item

Actions (login required)

Item Control Page