How much fish have we got?

The Shifting Baselines Toolset is presented to the public and press on Wednesday 14 to Friday 16 this November 2007.

When: Public symposium 1pm to 5:15pm, Wednesday 14th November
Where: Owen Glenn Building, Wynyard Street, University of Auckland city campus.

The meeting will be launched with a public symposium on Wednesday 14 November. Scientists will be available for interviews on the 14th and on other days by arrangement.

With evidence in hand we can see that a multiple of human impact factors interfere with fish stocks distribution patterns. The vivid case study examples from a research group called Shifting Baselines form a package or a toolset that illustrate the problems. With flash animations for a good comprehension of each problem their “Back flash files” are made available online: http://www.incofish.org/Workpackages/Wp2/Toolset.php

Examples of their research highlights are listed below:

• Peru: Spatial Distribution: Peruvian Hake since 1970 (IMARPE)

• Colombia: Abundance: ‘Then and Now’: decline in demersal fish biomass in the Colombian Caribbean Sea (UNAL)

• UK: Size of Individuals: Size Matters! The rapid decline of whiting in the North Sea, (UNIABDN)

• Denmark: Species Diversity: Highlighting 400 years of shifting species distribution, (RUC)

Data collected by the Shifting Baselines group has highlighted temporal change in the spatial distribution, abundance, diversity and individual size of selected species in particular ecosystems.

For a deeper look into the background data or further exploration, the datasets behind the case studies are made available to the public online: http://fishbase.sinica.edu.tw/tools/wp2_d22/main.php

The “Shifting Baselines” workpackage addresses the 'shifting baseline syndrome'. In essence, this problem has emerged as each generation of fisheries and environmental scientists has accepted existing stock size and species composition as the baseline against which temporal changes are measured.

However, if stocks are progressively depleted, a shift in the baseline occurs over time.

This results in an accommodation of the creeping disappearance of resource species, and the application of inappropriate reference points for the evaluation of economic losses due to over fishing, and the identification of targets for rehabilitation policies.

To resolve this problem, criteria for selecting key aquatic resources (stocks) within particular large marine ecosystems have been developed:

• Examine the patterns of long term change in selected coastal ecosystems and thereby establish targets for the restoration and sustainable use of living marine resources.

• Identification, validation and assembly of historical data (e.g. biomass, mean size, maturity, fecundity) relating to key aquatic resources in selected large marine ecosystems (LMEs)

• Collation, analysis and dissemination of the historical data collected and processed.

• Establish baselines against which the current status of aquatic resources and LMEs can be evaluated and restoration goals can be set.

Historical data on catch and effort, biomasses, length-frequencies, maximum sizes, size and age at maturity, growth rates, natural mortality, etc. are assessed, collated and analyzed to establish baselines against which the current status and restoration goals of key aquatic resources are assessed.

Likewise, historical data on catch and effort, production, biomasses, predator-prey interactions, flows, and habitat change are mined, assessed, collated and analyzed to establish baselines against which the current status and restoration goals of selected marine ecosystems can be assessed.

The development of this work has now come to its peak by developing the searchable datasets online and the Back flash files that explains and verifies that shifts in baselines have taken place and the causes behind them.

Shifting Baselines research group is the Workpackage 2 of the large scale research project INCOFISH. It is an EU funded project with scientific participants from 35 institutions and private enterprises from 22 nations worldwide.

The objectives of INCOFISH are to conduct specifically targeted strategic research suitable to contribute to the goals set by the World Summit for Sustainable Development in Johannesburg, such as restoring healthy fish stocks and ecosystems by 2015.

Source : Census of Marine Life