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Effects of Predicted Climate Change on Australian Fisheries ... and More!
Brown, C.J., Fulton, E.A., Hobday, A.J., Matear, R.J., Possingham, H.P., Bulman, C., Christensen, V., Forrest, R.E., Gehrke, P.C., Gribble, N.A., Griffiths, S.P., Lozano-Montes, H., Martin, J.M., Metcalf, S., Okey, T.A., Watson, R. and Richardson, A.J. 2010. Effects of climate-driven primary production change on marine food webs: implications for fisheries and conservation. Global Change Biology 16: 1194-1212.

The authors write that "climate change is altering the rate and distribution of primary production in the world's oceans," which in turn "plays a fundamental role in structuring marine food webs (Hunt and McKinnell, 2006; Shurin et al., 2006)," which are "critical to maintaining biodiversity and supporting fishery catches." Hence, they are keen to examine what the future might hold in this regard, noting that "effects of climate-driven production change on marine ecosystems and fisheries can be explored using food web models that incorporate ecological interactions such as predation and competition," citing the work of Cury et al. (2008), which is what they thus set out to do.

What was done
Brown et al. first used the output of an ocean general circulation model driven by a "plausible" greenhouse gas emissions scenario (IPCC 2007 scenario A2) to calculate changes in climate over a 50-year time horizon, the results of which were then fed into a suite of models for calculating primary production of lower trophic levels (phytoplankton, macroalgae, seagrass and benthic microalgae), after which the results of the latter set of calculations were used as input to "twelve existing Ecopath with Ecosim (EwE) dynamic marine food web models to describe different Australian marine ecosystems," which protocol ultimately predicted "changes in fishery catch, fishery value, biomass of animals of conservation interest, and indicators of community composition."

What was learned
The seventeen scientists state that under the IPCC's "plausible climate change scenario, primary production will increase around Australia" with "overall positive linear responses of functional groups to primary production change," and that "generally this benefits fisheries catch and value and leads to increased biomass of threatened marine animals such as turtles and sharks," adding that the calculated responses "are robust to the ecosystem type and the complexity of the model used."

What it means
In the concluding sentence of their paper, Brown et al. state that the primary production increases suggested by their work to result from future IPCC-envisioned greenhouse gas emissions and their calculated impacts on climate "will provide opportunities to recover overfished fisheries, increase profitability of fisheries and conserve threatened biodiversity," which is an incredibly nice set of consequences to result from something the world's climate alarmists claim to be an unmitigated climate catastrophe.

Cury, P.M., Shin, Y.J., Planque, B., Durant, J.M., Fromentin, J.-M., Kramer-Schadt, S., Stenseth, N.C., Travers, M. and Grimm, V. 2008. Ecosystem oceanography for global change in fisheries. Trends in Ecology and Evolution 23: 338-346.

Hunt, G.L. and McKinnell, S. 2006. Interplay between top-down, bottom-up, and wasp-waist control in marine ecosystems. Progress in Oceanography 68: 115-124.

Shurin, J.B., Gruner, D.S. and Hillebrand, H. 2006. All wet or dried up? Real differences between aquatic and terrestrial food webs. Proceedings of the Royal Society B -- Biological Sciences 273: 1-9.

Reviewed 15 September 2010