What I would like to know is how culling the corvids from aset area will have any sort of scientific purpose?

I understand that this form of culling may work with non swimming mammalian predators on small offshore islands.

I have some breaking news for the people suggesting this ....

Birds can fly !!

if you remove all the magpies from a 1km square, do you seriously believe that there will not be any magpies at the end of the grouse , sorry I mean songbird breeding cycle.

Please re-think this matter and only suggest a viable experiment 

Before we take the moral high ground, please remember that RSPB were licensed by Scottish Natural Heritage to take or kill  sea birds in the Firth of Forth by the use of alphachloralose and Secanol poison.

Gull culling using poison also took place on Fidra and the Isle of May in the Firth of Forth.

See here for full details.

also

SNH Letter confirming this happened.

160 Magpies all together locally does anyone seriously think they will allow small birds to survive if they stay in that number.Of course proof of that before the red herring comes up of non belief. 

davidbinos said:

Before we take the moral high ground, please remember that RSPB were licensed by Scottish Natural Heritage to take or kill  sea birds in the Firth of Forth by the use of alphachloralose and Secanol poison.

Gull culling using poison also took place on Fidra and the Isle of May in the Firth of Forth.

See here for full details.

also

SNH Letter confirming this happened.

Predator control is a large part of any nature conservation job, and is often essential in order to protect other species. Often it is invasive and non-native species that are removed, but sometimes native predators have to be culled to protect other species.

Gulls for example, need to culled so that their population is kept in check and doesn't expand too much, especially where coastal seabird breeding properties such as the Isle of May and the Firth of Forth are concerned. The Gulls will take the eggs and chicks of anything they can, because seabird and wader nests are SO exposed! It's only a small proportion of the gull population that will do this, most will feed on fish, but if the population is left to expand, then more and more will start predating seabirds and waders, and the decline of seabirds will become even more rapid. In cases like this, where the results can actually be seen, I agree with culling to control the population, but not remove them completly.

But I don't see how culling a small number of magpies and crows will affect the songbird population. Most farms, grouse farms etc trap and kill crows anyway, and songbird numbers are still declining, so how would culling these animals make any difference? Songbird Survival tried this in 2009, but didn't go through with it for some reason or other, see link: http://www.guardian.co.uk/theguardian/2009/apr/20/magpies-protect-cull-songbird-survival

All of their 'evidence' is based on such flimsy research! The RSPB said:   "A recent scientific review of the way predatory birds impact on songbirds, commissioned by SongBird Survival from the British Trust for Ornithology largely exonerated crows, magpies and raptors from causing songbird population declines. Our own and other reputable scientific research suggests that intensification of farming practices and other land use changes, encouraged by the Common Agricultural Policy, have driven the particular declines of farmland bird species across the UK and more widely in Europe"

Songbird Survival have nothing to base their claims on! Plus, birds can fly, and if it's a good feeding site, surely more birds will continue to drop in? The cull may cause a slight increase in survival of songbirds, but that won't mean that their decline is completely due to crows and magpies predating them. They only take eggs and chicks for a couple of months each year, but reduction in food and habitat affects songbirds all year round. Also, cats take more birds than crows and magpies do, so if anything, surely they should cull cats?! Now that would have a big effect on songbird survival!

Also, I think they are just doing it under a General Licence, as this does allow you to kill crows and magpies. If they can convince that they want to prove that corvids are the reason for songbird decline, they might just get away with it. But if a cull is what it takes to prove that corvids are not the main reason for the decline of songbirds, it should be done by an organisation who does not have an alterior motive - songbird survival is blatently a front for grouse farming, which is why they want to expand the cull to raptors if they get good results from this cull. Idiots.

Thank you for response Sarah.

Re "Also, cats take more birds than crows and magpies do,"  I would be interested in the scientific reference to the evidence that supports that assertion.

Re "Most farms, grouse farms etc trap and kill crows anyway"

Grouse are not farmed, and again I would like to see the research that showed that most farms trap and kill crows.

Re "Predator control is a large part of any nature conservation job, and is often essential in order to protect other species. Often it is invasive and non-native species that are removed, but sometimes native predators have to be culled to protect other species."

I could not agree more.

Is that also why RSPB "also control foxes and crows at Abernethy Forest in Strathspey, where poor weather and predation resulted in low productivity of the increasingly rare capercaillie during the 1990s."

RSPB policy on predator control.

Controlling predators

"To achieve our conservation objectives, the RSPB sees the killing of birds and mammals as a matter of last resort.

We aim to restore populations of wildlife principally through habitat management and any measures to control predators is considered carefully, case-by-case. Nevertheless, we recognise that ground-nesting birds are especially vulnerable to predation by both mammals and crows.

To understand the role of controlling predators better, the RSPB is undertaking a scientific trial control of foxes and carrion crows on some of its nature reserves where lapwings nest, in conjunction with positive land management.

We also control foxes and crows at Abernethy Forest in Strathspey, where poor weather and predation resulted in low productivity of the increasingly rare capercaillie during the 1990s."

Hi davidbinos,

Actually, the BTO did a study quite recently into the effects of cats on songbirds, but there are many other investigations that have been carried out by other organisations (i think the RSPB may have done one, but not sure). Here's what the BTO says: http://www.birdguides.com/webzine/article.asp?a=2117

Grouse, Pheasants and other game birds are farmed for shooting by hunting estates, who regularly kill predators - stoats, weasels, corvids, foxes and occasionally birds of prey - see links below. The reason I mentioned grouse farming etc. is because I heard that quite a few of the influential members of Save our Songbirds are a part of this industry.

http://www.timesonline.co.uk/tol/news/environment/article3101294.ece 

http://www.animalaid.org.uk/h/n/CAMPAIGNS/pheasant/ALL///

And yes, I assume that is why the RSPB kills foxes and crows - to protect the important, yet highly vulnerable population of ground-nesting capercaillie. I agree that culling of predators should be a last resort, and if it's scientifically proven to actually have a positive effect on vulnerable species that may otherwise experience a severe decline in numbers, then I agree that it should take place. But this current cull doesn't seem to be backed up by any research, not even by the research that Save our Songbirds did themselves, and therefore, I don't support it. Because it makes no sense.

"Grouse, Pheasants and other game birds are farmed for shooting by hunting estates"

Pheasants and other game birds are reared ( farmed ) Not grouse though.

"But this current cull doesn't seem to be backed up by any research, not even by the research that Save our Songbirds did themselves, and therefore, I don't support it. Because it makes no sense."

In one way you say there is no research to back this, yet this very scheme is research to prove or disprove their hypothesis. Or are you saying that they and G&WCT trust should not do the research?

"Magpie densities in urban parkland in Manchester in the
late 1980s were higher than had previously been recorded
in other urban areas, and during the same period fewer
than 5% of the blackbird nests in the parkland produced
fledged young (Groom 1993). Although the cause of most
nest failures was unknown, predation was the most
important cause where it was known, and most of this
was attributed to magpies"

Groom DW (1993) Magpie Pica pica predation on blackbirds
Turdus merula nests in urban areas. Bird Study 40:
55–62.

My position is not that predator control should not take place. I take the opposite position and agree with you, it is necessary. My argument is that it is so easy to get into the "one bird good, one bird bad" argument and posit the argument that it is ok if RSPB is doing it, but not anyone else. Or not be up front about the fact that RSPB do it.

To take the extreme view, if a gamekeeper or anyone for that matter killed gulls by poison, or destroyed nests, then it would rightly be called a wildlife crime. Yet when a conservation body does it, it is conservation measures.

I have no problem with the RSPB carrying out predator control, my issue is with the types of post I see on this and other fora, where either the posters are not aware of what is going on in RSPB reserves, or chose to be selective in their research.

I'm saying that if the research has to happen to prove whether or not crows, magpies etc do have a significant negative impact on songbird populations, then it should be carried out by a group that has no hidden agendas. E.g. the BTO or a University etc. Somebody as neutral as can be. But a lot of research done so far seems to say that magpies and crows don't have too much of an effect on songbird numbers.

I am aware that the RSPB and other conservation groups carry out predator control, but they only do it as a last resort, and because it is necessary. I do not think that killing foxes to protect farmed game birds, for example, is really necessary. But even if they do prove that crows and magpies are having a significant effect on songbird populations, what will come of the results? We can't have a country-wide cull of these birds, but if they are affecting sonbird numbers, surely this would be the only way to prevent that?