Friday, January 28, 2011

When we don't hear the whole story

I have received two worrying posts via Facebook in the last 24 hours.

The first was a link from an acquaintance of mine who traps and does everything he can to promote that activity. He was interested by an article Biodiversity benefits from new snaring scheme - National Park agrees about how black grouse conservation in Scotland is being aided by trapping predators such as foxes and weasels. Which is no doubt true, but if one looks a bit deeper into the story, the RSPB are the other lead body working on black grouse conservation. Their emphasis is very much on habitat management, and "reducing fox and crow predation where essential". Notice the Game & Wildlife Conservation Trust never mentioned crows. By cherry-picking at bits of the whole story, they have come up with an article that shows how wonderful snaring is.

Perhaps more worrying, because it is about something I agree with, is this video made by Hellmans in support of food security.

The problem here are the numbers they quoted for blueberry production in NS: "NS production in 2007 was half what it was in 2003". Now, this is actually true, 13500 tons, down from 29300. And if this were a trend, yes, we should be worried, but it is not born out by the statistics. One could equally have compared 2008 with 2007 and said that harvest is up 54%.

Take a look and you will see that 2003 saw an abnormally high production, with an unprecedented yield of 0.77 tons/acre, while 2007 was low at 0.34 tons/acre. The ten year average was 0.49 tons/acre (my maths). No doubt yields vary considerably according to the weather and other factors.

What should be noted from these figures is that the acreage under production has risen fairly steadily in the past 10 years. Totally counter to the argument that the video is making, and however much one wants to support a cause like food security, one has to wonder just how reliable all their other numbers are.

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