This thing called life

The best science and the worst policy – catch limits set for the super trawler

Yesterday, in the wake of the banning of the super trawler, Australia’s Nobel Prize winner Brian Schmidt called for a more scientific approach to policy. He pointed out that in Britain, science is embedded in every government department, while in Australia, public confidence in scientific advice has been damaged.

Today, a member of the Small Pelagic Fishery Resource Assessment Group, which makes recommendations about quotas, said that the doubling of the jack mackerel quota occurred for economic, rather than scientific reasons.

This puts science in an awkward position. When policies are justified by science, the public has every right to expect that the evidence was collected in a manner appropriate to the question, and that conclusions were based on data. Science must be both rigorous and independent, if it is to be trusted.

Unfortunately, saying that changes to the jack mackerel catch limits were based on “the best available evidence”, is not very comforting in this case. This is not to say that the scientists did a poor job of analysing the data. Indeed, the scientific report* used to justify the adjustment urged due caution because the egg survey was designed to study spawning dynamics of blue mackerel and the data were therefore not collected at the right time or in the right place for optimally estimating the biomass of jack mackerel.

The Australian Fisheries Management Authority website defends the decision by saying: “AFMA uses the best available science to set catch limits and seven of Australia’s and the world’s leading fisheries scientists have publically (sic) supported the science.”

There is nothing wrong with that statement, except that it implies that the world’s leading fisheries scientists support the catch limits set by AFMA. The scientists might be dismayed at the way the research has been used (or ignored) but they have every right to defend the science.

The question is not about the science, but about the application of the science. The Resource Assessment Group within the AFMA had the task of reviewing the science and making a recommendation about total allowable catch for these species, and a member of the group has told us that the decision was not based on science.

To be more precise, Graham Pike said in The Australian: “Seafish Tasmania Pelagics, was registered on April 21, about a month after AFMA (wrongly) doubled the jack mackerel quota to economically justify the venture.” This was not a failure of science, but of the interaction of science and policy.

The AFMA defends the super trawler by adding, “There is no evidence that larger boats pose a higher risk to either commercial species or broader marine ecosystem.” This is another statement that does disservice to the science. It is written as if the research has been done and no evidence was found, rather than admitting that no data has been collected about the impact of larger boats. It seems to imply that the people who oppose the super trawler must prove that big boats pose a higher risk, rather than acknowledging that it is the responsibility of Australian fishery managers to determine the risk.

Both of these statements could be used in a classroom as examples to teach critical thinking. They are very similar to logical fallacies known as ambiguity and burden of proof. Scientists are trained to spot these types of errors and avoid them in their own thinking and writing. Politicians are trained to employ these types of statements, particularly when they are engaged in an activity known as “spin”.

Fisheries managers serve the politicians and employ the scientists. They live in a strange no man’s land where political spin is not normally necessary and science is someone else’s job. And yet, as Brian Schmidt said, the public confidence in AFMA has broken down.

Perhaps this is a good time to seriously consider more scientific advisers to government at all levels. Imagine the benefits of introducing critical thinking, rigorous logic and independence into every department and agency. If the goal is to restore the public’s confidence in decisions made by government, then the first step is to recognise that the public knows the difference between evidence and spin.

So please don’t give us evidence that decisions were based on spin. The trick is to spin it so that we believe that decisions are based on evidence.

  • Neira, F. J. (2011). Application of daily egg production to estimate biomass of jack mackerel, Trachurus declivis – a key fish species in the pelagic ecosystem of south-eastern Australia. Final report to the Winifred Violet Scott Charitable Trust. Fisheries, Aquaculture and Coasts Centre, Institute for Marine and Antarctic Studies (IMAS), University of Tasmania. 42 pp.