Thank you!
He appended a summary, but I went to the study and looked at the math, and you can too.
See >> https://www.nature.scot/doc/naturescot-research-report-1345-investigating-role-badgers-meles-meles-lamb-predation-scottish-farms
In a country (Scotland) of 6.61 million sheep, they found 14 lambs on 29 surveyed farms over two years that they think *might* have been predated on by fox, but there were no eyewitnesses, and no video.
To put it another way, looking at 58 farm-years (29 x 2), they found 14 lambs that they think *might* have been predated on by fox, but 85 percent of these lambs (12 out of 14) might have been predated on by dog, based on dog DNA being present.
That sounds like a very low number.
But do you see the problem?
How many sheep were raised over two years on these 29 farms?
It’s strikingly odd that this report does not say.
This report also does not give us non-predator mortality or causality on these farms — another odd omission.
With no denominator and no “compared to what?” number, we are given no idea of how truly rare fox predation appears to be.
What this report *does* make clear is that if *any* sheep in Scotland are being predated on by wild animals, it’s very, very rare, is never a badger, and is likely to be a dog.
As for lamb mortality in Scotland, it’s *very* high, as it is all over, since sheep are naturally bad parents and farmers select for breeds that produce twins and triplets that are often born under-weight, and too often dead.
How common is lamb mortality in Scotland?
Very!
See >> https://www.cambridge.org/core/journals/journal-of-agricultural-science/article/abs/effects-of-breed-breeding-system-and-other-factors-on-lamb-mortality-1-causes-of-death-and-effects-on-the-incidence-of-losses/74BAF995A9B5BAC0B0D89EC73D551CE8
Here we learn that 25 percent of sheep born (632 out of 2453) were born dead or died shortly after birth.
Wow!
So, bottom line: there’s about 25 percent lamb mortality in upland Scotland, and a sheep farm might lose as much as one lamb every four years to a fox (14 lambs over 58 farm-years).
And badger killing sheep?
No evidence of that at all.
Want to succesfully reduce lamb mortality? Cross-breed (see second link), do supplemental feeding, and provide shelter from the weather.
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