Thread by @SteB777

Can I briefly explain the ecological thinking error, in this thinking. You say, there are too many crows, Foxes and Badgers. Well what are you going to do about it. The ecologically ignorant, say, well cull them, and there will be far less.
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https://twitter.com/TonyJuniper/status/2040700088918388895

However, it doesn't work like this, populations of memo-predators like Foxes and Crows aren't determined by predation a.k.a. culling. Common sense reasoning has it, that if you kill ten thousand Crows or Foxes, then the population is going to be ten thousand less of them.
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The population density of say Foxes, isn't determined by how many get killed by humans. It is determined by territoriality and ecological carrying capacity. Most young Foxes don't live much past the first year, because they fail to establish a territory.
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In other words, if you randomly kill, even quite a lot of Foxes, it will do nothing to reduce the overall Fox population, just allowing more young Foxes to survive as there are now more empty territories. This is counter-intuitive.
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A lot of research has been done in Europe, to find out what level of culling, will suppress the Fox population, because they can be a vector for rabies. When there is an outbreak, they need to control the population.
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It has been found, that even quite high levels of Fox culling, do nothing to suppress the population, and it takes very high sustained culling, to suppress the population, which only lasts as long as this continues.
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It is much the same with Crows etc. If you wanted to reduce the population of Crows and Foxes, to say protect, breeding Curlews, you would need very high sustained culling, killing vast numbers, not just in Curlew breeding areas, but outside it.
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Even if you killed nearly all the Foxes and Crows in a Curlew breeding area, it would only be weeks, before Crows and Foxes from outside the areas, moved into the empty territories. Hence, you would need this intense level of culling everywhere.
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This isn'tt theorhetical. I saw it happen, when they started culling Crows, in very large numbers at Fenns and Whixall Moss NNR. Most nest predation is only done by 5-15 Crows, and in 2023, they killed 191 Crows, and it had no visible effect, on Crows nest predation behaviour.
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We can all agree, that it would be better for there to be less predation of Curlew nests, but it is ecologically naive, to believe this could be simplistically achieved, by moderate culling. To suppress the populations, would require massive sustained culling, on a huge scale.
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When this Crow killing started, for a few weeks, there was a big reduction in Crow nest predation. But as soon as non-breeding Crows realized there were no territorial Crows left, to chase them off, it was back to square one.
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In subsequent years there was not even a brief respite, and I still see upwards of 15 Crows move onto the Moss, during the nesting season. No different to prior to the culling, In other words, they are killing huge numbers of Crows, for no positive effect.

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In fact, after 2023, they started catching far less Crows in Larsen traps.

This simplistic, we will have to talk about difficult subject of culling, ignores it doesn't work and what a bloody level of culling would be necessary.

13/en.wikipedia.org/wiki/Larsen_tr…

There can be unintended consequences, and I warned the Fenns and Whixall Moss NNR, @NaturalEngland management about this, and they ignored what I warned them about.

It has resulted in far more nest predation behaviour, by avian nest predators, other than resident Crows.
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You see, territorial Crows on the Moss, controlled non-resident Crows, Ravens, raptors like Common Buzzards, Red Kites, Marsh Harriers, and large gulls like Lesser Black-backed Gulls, from engaging in nest predations, by mobbing them.
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Prior to the Crow killing, I rarely saw Ravens, and raptors engaged in nest predation behaviour because they'd be harassed by the territorial Crows. Now, every day, these other avian nest predators, are engaged in nest predation, in the Curlew breeding areas.
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This is seriously problematical, because these other avian predators are far more of a threat to large chicks, fledglings, and even adult Curlews. None of the NNR managers have ecological qualifications, or a grasp of ecological principles.
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Finally, to conclude, this is not just my opinion, because the RSPB @Natures_Voice did Curlew trial management, including predator control, and it did nothing to improve Curlew breeding success.

18/rspb.org.uk/helping-nature…

There are so many other issues I have not dealt with in this thread. But it must be noted that pro-shooting organizations are promoting predator control, for Curlew conservation for ulterior motives, and unfortunately gullible conservationists get taken in by it.
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As I imply, controlling predators numbers is a bloody business, unpopular with the public, and gamekeepers illegally kill protected species like birds of prey, so are desperate to sell what they do, as good for conservation. @IoloWilliams2 @WildJustice_org @ChrisGPackham
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I will be blogging far more about this, so watch this space.
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