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2010_Blanchardetal_Indiseas_ICESJMarSci.pdf (683.7 kB)

Trend analysis of indicators: a comparison of recent changes in the status of marine ecosystems around the world

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journal contribution
posted on 2023-05-18, 10:04 authored by Julia BlanchardJulia Blanchard, Coll, M, Trenkel, VM, Vergnon, R, Yemane, D, Jouffre, D, Link, JS, Shin, Y-J
Time-series of ecological and exploitation indicators collected from 19 ecosystems were analysed to investigate whether there have been temporal trends in the status of fish communities. Using linear and non-linear statistical methods, trends are reported for six indicators (mean length of fish in the community, mean lifespan, proportion of predatory fish, total biomass of surveyed species, mean trophic level of landings, and inverse fishing pressure), and the redundancy of these indicators across ecosystems is evaluated. The expected direction of change for an ecosystem that is increasingly impacted by fishing is a decline in all indicators. A mixture of negative and positive directions of change is recorded, both within and among all ecosystems considered. No consistent patterns in the redundancy of the ecological indicators across ecosystems emerged from the analyses, confirming that each indicator provided complementary information on ecosystem status. The different trends in indicators may reflect differing historical exploitation patterns, management, and environmental regimes in these systems. Commitment to monitoring programmes and development of system-specific baseline, target, and threshold reference levels are required. Improved understanding of the responsiveness and performance of ecological indicators to management actions are needed to address adequately whether ecosystems are recovering from, or being further impacted by, fishing, and whether management targets are being met. The relative effects of multiple environmental and ecological processes as well as multiple human-induced stressors that characterize exploited ecosystems also need to be quantified.


Publication title

ICES Journal of Marine Science








Institute for Marine and Antarctic Studies


Academic Press Ltd Elsevier Science Ltd

Place of publication

24-28 Oval Rd, London, England, Nw1 7Dx

Rights statement

© 2010 The Author(s) Licensed under the terms of the Creative Commons Attribution Non-Commercial License ( (The above website no longer exists see_

Repository Status

  • Open

Socio-economic Objectives

Assessment and management of Antarctic and Southern Ocean ecosystems

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