Corvid cull looming

Good morning Sarah,

"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."

There is also a fair amount that shows they do. If you do a literature search and make up your own mind on the balance of views. The reference section of RSPB Research Report no 23 is a good place to start, though in my opinion, this is rather selective, so as to push the authors point of view.

"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?"

This study, regardless of the results, will be an addition to research already done. As RSPB says, there is a paucity of relevant research in this area. Then, before any decision is made, the various studies will be reviewed and a consensus view hopefully reached.

After all, the RSPB have asked that more research be done,

"Further studies that provide clear evidence of whether
predators limit populations of their bird prey are needed.
While such evidence is best obtained from predator
removal experiments, these are not always
straightforward, so an alternative approach is to
compare populations of bird prey in areas, or at times,
with differing predator densities. So far, most studies
have been of ground-nesting birds, and similar studies
of songbirds are needed, for example in urban and
suburban areas."

Gibbons DW, Amar A, Anderson GQA, Bolton M, Bradbury RB, Eaton MA, Evans AD,
Grant MC, Gregory RD, Hilton GM, Hirons GJM, Hughes J, Johnstone I, Newbery P,
Peach WJ, Ratcliffe N, Smith KW, Summers RW, Walton P and Wilson JD (2007).
The predation of wild birds in the UK: a review of its conservation impact and
management. RSPB Research Report no 23. RSPB, Sandy.

Sorry if this throws a spaniel in the works but, reported in the Scotsman newspaper on the 28th of January, 2011.........

The article is entitled "Feathers fly as conservationists reveal plan to cull birds"

And there's a section which reads.........

"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".

Find the full story here...... http://www.scotsman.com/news/Feathers-fly-as-conservationists-.6704658.jp

Perhaps we should be culling the farmers instead!

Frank.

And at the end of the article, 20-30 crow species......

Now if they don't know what a corvid is they certainly should not lead a cull.

Anyone want to make a list of 30 corvids.......

1 Raven

2 Carrion Crow

3 JAckdaw

4 Jay

5 Hooded Crow

6 Magpie

7 Chough

8 Rook

....

erm I've run out.....

"If you do a literature search and make up your own mind on the balance of views." - I have done, and I have made up my own mind in balance of the views!

What I'm saying is I don't agree with this cull. As you pointed out in your RSPB quote, there are methods other than culling that can be used. And as Dulaich pointed out in his quote, some research "commissioned by SongBird Survival from the British Trust for Ornithology largely exonerated crows, magpies and raptors from causing songbird population declines."

Revealing use of the words "largely exonerated" Look at the raw data rather than the report's conclusions.

A very large proportion of RSPB membership are the "garden twitcher variety" and live in urban areas. Also a good percentage of the bequests left to RSPB come from that class of member.

Telling them that farming methods and habitat change is largely to blame for the fact that they see a large decline in the songbird population visiting and nesting in their gardens is refuted by the evidence of their own eyes. They see an increase in predation by the ever increasing number of corvids and raptors. Read some of their comments on the various fora where this issue is being debated. That is, the views of ordinary RSPB members  and members of the public who cannot be accused of pushing some hidden, dark agenda. Be it from a pro or anti shooting/hunting/fishing point of view.

"What I'm saying is I don't agree with this cull."

How else wold you suggest the research is carried out?

" As you pointed out in your RSPB quote, there are methods other than culling that can be used.""

What methods applicable to the urban garden and parks and ordinary individuals would you suggest?

THE PREDATION OF
WILD BIRDS IN THE UK
A review of its conservation
impact and management

Gibbons DW, Amar A, Anderson GQA, Bolton M, Bradbury RB, Eaton MA, Evans AD,
Grant MC, Gregory RD, Hilton GM, Hirons GJM, Hughes J, Johnstone I, Newbery P,
Peach WJ, Ratcliffe N, Smith KW, Summers RW, Walton P and Wilson JD (2007).
The predation of wild birds in the UK: a review of its conservation impact and
management. RSPB Research Report no 23. RSPB, Sandy.

"One of the most convincing ways to determine whether
a predator is limiting a population of its prey is to remove
the predators, or reduce their numbers, and see if prey
populations increase. Such studies will also show whether
predator removal is a useful management tool. Ideally,
these studies should be done as formal experiments, with
predators removed in some areas or years, but not in
others, and the impact on prey measured (Newton 1998)."

Newton I (1998) Population Limitation in Birds. Academic Press,
London

By its own definition the word research would suggest that the decline in the population of songbirds should be looked at, studied, questioned or investigated, facts and figures gone in to.

Surely a cull would technically be one end result, one solution to the problem AFTER the research data had been analysed.

If a cull were to go ahead, under the banner of a research project, and the population of songbirds did not recover, would they then be able to UNCULL all the birds which would have been wrongly persecuted and destroyed?

If "SongBird Survival from the British Trust for Ornithology largely exonerated crows, magpies and raptors from causing songbird population declines."   surely then they can in no way justify a cull of said species.

Frank.

davidbinos said:

However, this particular issue revolves around an attempt by the G&WCT to carry out that very research to provide those "facts and figures".

I'm sorry, but I have to disagree.

It appears to me that they are trying to enforce a solution before they have worked out what the problem is!

I don't see how a cull can be called research. A cull would be ONE solution IF the research showed that Corvids and BOP's were to blame.

I don't see how they can turn round a say "well, we don't think it is the Corvids and BOP's, we think it's the farmers. But we'll shoot the birds anyway"!!!

Frank

"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." (my italics)

So the cause of most nest failures was unknown. In the minority of cases where a cause could be attributed predation was seen as most significant, and a majority of this significant proportion of the minority was down to Magpies.  That doesn't sound like a convincing case for culling Magpies to me.

Research needs to establish the cause of nest failure in the majority of cases before the killing begins.

JBNTS

Hello Frank. There is no large scale cull as part of this proposed research. As I understand it a small number of sites 3 - 7 in different areas of the country will be used for the study area. There will be comparisons made between two song-bird sites in each location. One left as is as a control, and the other with cage traps. ( No shooting as far as I am aware )

Hardly a large scale culling of corvids.

One of the main arguments I hear being put forward by many of those opposed to this, is that it is the "pro shooting" G&WCT that is carrying out the research.  The G&WCT may be the bogey-men of the anti shooting brigade, but their scientists and research methods and reporting, are accepted as rigid by those involved in scientific research, and is thoroughly peer reviewed.