Media cod claims: "the most wrong number ... ever reported"
03 October 2012
Recent media reports about the number of adult cod left in the
North Sea came under scrutiny during the BBC World Service's More or
Less programme recently.
The programme makers aimed to discover the truth behind
headlines that claimed only
100 cod were left in the North Sea. What they found was in fact
The BBC's Hannah Barnes indicated that the
disparity between the media headlines and the true figure
for cod in the North Sea was huge and that at least one media
headline "... could be a More or Less record, the
most wrong number we have ever reported."
Cefas' Dr Carl O'Brien and others were interviewed for the
programme. Dr O'Brien explained that cod start to mature at ages
one and two and are fully mature by age six. He
continued: "The bulk of the mature cod in the North Sea at the
moment is constituted of fish which are actually younger than 7
years of age."
Unfortunately, despite having access to the
latest ICES data, UK journalists misunderstood those
figures and chose to class an adult cod as over 13.
Hannah Barnes said: "That's not really an adult cod, it's
an ancient cod. Now we shouldn't be surprised that there
are very few cod over 13, just as we aren't suprised that there are
hardly any humans older than a hundred."
And what of the
Sunday Times' claim that there are only 100 adult cod
in the North Sea? Referring to the same dataset used by
the paper, the actual figure is 21 million. The
newspaper has since printed a correction and changed aspects of
their original article online.
And as for the Daily Telegraph's claim that there
are only 100 cod left in the North Sea? A more
accurate estimation, suggested the programme, is
436,900,000 cod left in the North Sea. It is this
disparity that the More or Less programme claimed to be
"the most wrong number we have ever reported".
The programme went on to discuss how difficult it is
to measure fish stock numbers.
Dr O'Brien said: "As fisheries scientists we do not try to count
every single fish in the sea, instead we collect information from
three main sources: from landings at ports, from fishermen
themselves, and from research vessels.
"...as a rough estimate we aim to sample a minimum of roughly
200 fish per 1,000 tonnes landed. Our methods are rigorous and
robust with small errors of uncertanty."
He went on: "The latest international assessment shows
there's been a gradual improvement in the status in the stock over
the last few years. And the amount of mature fish is actually
increased ... and does show signs of further improvement."