Nesting Robin and the affects of Magpie and other predators on Song Birds

John_Rambo

Hi everyone.

I have a little robin nesting in my garden, he (or she) is collecting dog hair from the kennel and flying in to a hole in the thick ivy and climbers on my wall. The problem is I have a magpie invasion lately. Will they harm the robins? Is there anything I can do to get them out of the garden? The dog keeps the cats at bay and the robin isn't bothered by the dog and the dog ignores the robin.

Thanks.

Judgement Day

Hell, all you can do is let nature take its course. The magpies will take whatever they can get, eggs or nestlings and the best thing you can do is take a back seat. Chasing the magpies away will probably have little effect as you can't be on guard 24 hours but perhaps the nest will elude them.

jwshooter

That's a problem we don't tolerate in the country side . vermin like magpies ,grey crows ,jays ,foxes are controlled .

with out this song bird populations would plummet ,to a worse state than they are at present .
my garden has a huge amount of song birds ,i fed them through the hard winter and most of them stayed near the feeders .my garden is big and on woodland style and is ideal for them .

to sit back and let magpies/vermin take song bird chicks is a total display of ignorance .

Mothman

jwshooter wrote: »

That's a problem we don't tolerate in the country side . vermin like magpies ,grey crows ,jays ,foxes are controlled .

I'm in the countryside and you don't speak for me. What is ones persons vermin may be cherished by another.
From my point of view I may not cherish Magpie or Hooded Crow often, but never ever would I view Jays or Foxes as vermin and despite having poultry about the sighting of a fox is cherished. The family saw one yesterday at 4pm. A bit too close for comfort with the free range poultry about but we still felt priviledged
Just to be fully clean, I have controlled Magpie who had too much of a taste for Hen's eggs.

jwshooter wrote: »

with out this song bird populations would plummet ,to a worse state than they are at present .

This I believe is a far bigger issue than the "vermin" you mention.

my garden has a huge amount of song birds ,i fed them through the hard winter and most of them stayed near the feeders .my garden is big and on woodland style and is ideal for them .

Far play and is tackling part of the bigger picture part of what I believe to be habitat loss.

to sit back and let magpies/vermin take song bird chicks is a total display of ignorance .

I do believe there is a lot of ignorance, so use this forum as a platform to educate so we end up with less ignorance.

Feargal as Luimneach

jwshooter wrote: »

That's a problem we don't tolerate in the country side . vermin like magpies ,grey crows ,jays ,foxes are controlled .

with out this song bird populations would plummet ,to a worse state than they are at present .
my garden has a huge amount of song birds ,i fed them through the hard winter and most of them stayed near the feeders .my garden is big and on woodland style and is ideal for them .

to sit back and let magpies/vermin take song bird chicks is a total display of ignorance .

Untrue information you are giving. Read this.
http://www.rspb.org.uk/wildlife/birdguide/name/m/magpie/effect_on_songbirds.aspx

jwshooter

Feargal as Luimneach wrote: »

Untrue information you are giving. Read this.
http://www.rspb.org.uk/wildlife/birdguide/name/m/magpie/effect_on_songbirds.aspx

bullshine .

Feargal as Luimneach

jwshooter wrote: »

bullshine .

Why?

Mothman

jwshooter wrote: »

bullshine .

Is this just your personal opinion or would you point us to some info to counter the info in the link given in previous post?

Feargal as Luimneach

Mothman wrote: »

Is this just your personal opinion or would you point us to some info to counter the info in the link given in previous post?

I think jwshooter is talking bullshine:cool:

Mothman

This thread is heading downhill and I've locked it.
If someone has something positive to add to it PM me and I'll consider opening it tomorrow

Mothman

jwshooter took me up on my invitation and requested me to post a link to a study.

I'm happy for jwshooter to do and I'm reopening thread.

Please only deal with content of the posts

jwshooter

thanks Mothman .

over the last 30-40 years . song thrushes ,black birds ,sparrows and small birds in general have been in decline .why ? .

lets look at two situations .

one ......a shooting estate where game birds are hunted and reared .

on the ground there is no vermin ,cover crops are sown there is always free feed about ,birds flourish .
my garden and forest beside my house are the same , i keep a larson trap and will shoot any vermin i see .
i had a pair of jays that came during the snow to my feeders ,i left them and the crows as it was a time for good will ,but not during nesting season .

two ......a patch of ground say a public park /garden with no vermin control ,magpies grey squirrels etc forage as they see fit ,small birds will suffer .

to say vermin numbers are on the rise and song birds/birds in general are in decline ,this is true .
To say predation does not affect the small bird numbers is total miss truth ,where have all the wrens gone .

the game & wildlife conservation trust have a education & advice section . there is some very interesting reading ....singing fields is one .management facts sheet no 5 is also worth a read .

when your dawn chorus consists of a magpie chattering it will be to late

Dusty87

I agree with Jw (for once:p).
I seen that report by the rspb before and was a bit surprised. But then looking into it more i came across more info. Lets just say, judging by the reading i did on the net one night, birdwatch ireland are a lot better.

Kess73

I have to disagree that magpies have a huge or unbalanced impact under songbird numbers, and certainly not more of an impact upon songbirds than cats or man.


Yes magpies will raid a nest for eggs on occasion, yes they will kill young birds and yes they can also kill adults, but no more so that they have done for hundreds of years.

Songbirds and eggs are not a primary source of food for magpies, decades of ornithology by much more learned folk than myself has borne this as a fact not opinion. Insects, carrion, and rodents have been found to be more common in the stomachs of dissected magpies from rural areas than nestlings or eggs. In urban areas various household scraps and other man provided food sources have overtaken eggs and nestlings in the stomachs of dissected magpies. Nestlings, eggs, and on rarer occasions, adult songbirds still get eaten though, but they are not a main food source.

A picture has been painted in this thread of a dawn chorus consisting of just the chatter of magpies if something is not done to control magpies. I say that is rubbish. If there were truth to that then the last few hundred years would have seen the magpie take over as they would have wiped out everything else before any person decided they were vermin.

But nature at it's purist does not work that way, it operates it's own system of checks and balances. Magpie numbers can never outgrow the various sources of food in their territories, it is simply impossible as they would die out themselves, the same as any other organism on this planet if it exhausts it's food source.

What should make for interesting reading is the population spreads and numbers in the 2007/11 bird atlas for Ireland and the UK. I have only a tiny part in that with my two 10km tetrads, but in my two I get to take in an urban area consisting of a city and many of it's housing estates and a totally rural area which ironiocally has a gun club within the boundaries of that tetrad.

The funny thing is that one area does not have a larger or healthier population of songbirds than the other, despite the rural tetrad having a gun club that pretty much shoots or traps magpies where possible.

The songbirds within the rural area breed fine, raise their young and so on. But the denisity of most songbird populations there are matched by those in the areas that have a healthy population of magpie and other corvids.

The answer is very simple. Nature has provided a way for the birds in the magpie rich area to maintain their numbers. That way is larger batches of eggs. The blue tits for example are laying three to four eggs more a batch in urban tetrad over the rural one where there has been culling of magpies for years and years. Same thing happens in raptor territories with many songbirds, as I get to see daily with a sparrowhawk nest which is partially in view from my bedroom window.

Another natural check upon magpie numbers are raptors and larger corvids. I have seen far too many magpie fall victim to raptors and hooded crow (also carrion crow in areas that have them) to think that it is not a natural check on their numbers. Juvenile to adults all fall to raptors and hooded crow seem quite partial to raiding magpie nest and also to the fledged juveniles.


I have waffled on now for a bit, but I ask myself do magpie have an impact upon songbird populations? I have to say that they do, but it is not an unnatural impact and not one that has placed any songbird at greater risk than man made impacts have done, nor has the magpie has a greater impact than threats that are introduced by man like the cat.

Nature follows it's own course when not impacted upon by man, and has always done so. The connection between Magpie and songbird has been going on long before man even became aware of it, and the hundreds, even thousands of years of that connection has not led to a magpie dawn chorus, and as such the magpie is not the species that would be the one most likely to the advent of a dawn chorus without song, the dubious honour of being the most likely cause of such a songless dawn is man.

Feargal as Luimneach

jwshooter wrote: »

thanks Mothman .

over the last 30-40 years . song thrushes ,black birds ,sparrows and small birds in general have been in decline .why ? .

lets look at two situations .

one ......a shooting estate where game birds are hunted and reared .

on the ground there is no vermin ,cover crops are sown there is always free feed about ,birds flourish .
my garden and forest beside my house are the same , i keep a larson trap and will shoot any vermin i see .
i had a pair of jays that came during the snow to my feeders ,i left them and the crows as it was a time for good will ,but not during nesting season .

two ......a patch of ground say a public park /garden with no vermin control ,magpies grey squirrels etc forage as they see fit ,small birds will suffer .

to say vermin numbers are on the rise and song birds/birds in general are in decline ,this is true .
To say predation does not affect the small bird numbers is total miss truth ,where have all the wrens gone .

the game & wildlife conservation trust have a education & advice section . there is some very interesting reading ....singing fields is one .management facts sheet no 5 is also worth a read .

when your dawn chorus consists of a magpie chattering it will be to late

Shooting estates have a problem of taking vermin control to the extreme. Look at the plight of the Hen harrier in England. They are critically endangered there.
http://www.rspb.org.uk/ourwork/policy/wildbirdslaw/wildbirdcrime/birdsofprey.asp

Mothman

Feargal as Luimneach wrote: »

Shooting estates have a problem of taking vermin control to the extreme. Look at the plight of the Hen harrier in England. They are critically endangered there.
http://www.rspb.org.uk/ourwork/policy/wildbirdslaw/wildbirdcrime/birdsofprey.asp

The plight of the Hen Harrier is separate issue to what this thread is about, primarily song birds.

I cannot accept lumping Jays and Magpies together under the label of vermin.

Recently someone here said they hadn't seen a Jay for years. I've had the occasional year without a sighting but managed to see 4 this winter. I have also seen a Jay systematically go through the middle of a garden hedge and raid the nests but I wasn't cursing the Jay. They need to feed as well as does the Sparrowhawk who came and took "my" Chaffinch. i feel priviledge in seeing this kind of nature and its why I tend to my wild garden.

I don't hold the Magpie with the same affection. I'll accept I'm not being consistent but I'm human.

I believe there is a far bigger picture and a numbers of pieces to the puzzle of songbird decline.

Paddysnapper

jwshooter wrote: »

thanks Mothman .

over the last 30-40 years . song thrushes ,black birds ,sparrows and small birds in general have been in decline .why ? .

lets look at two situations .

one ......a shooting estate where game birds are hunted and reared .

on the ground there is no vermin ,cover crops are sown there is always free feed about ,birds flourish .
my garden and forest beside my house are the same , i keep a larson trap and will shoot any vermin i see .
i had a pair of jays that came during the snow to my feeders ,i left them and the crows as it was a time for good will ,but not during nesting season .

two ......a patch of ground say a public park /garden with no vermin control ,magpies grey squirrels etc forage as they see fit ,small birds will suffer .

to say vermin numbers are on the rise and song birds/birds in general are in decline ,this is true .
To say predation does not affect the small bird numbers is total miss truth ,where have all the wrens gone .

the game & wildlife conservation trust have a education & advice section . there is some very interesting reading ....singing fields is one .management facts sheet no 5 is also worth a read .

when your dawn chorus consists of a magpie chattering it will be to late

Very well said! I utterly agree with every word:)

jwshooter

Kess73 wrote: »

I have to disagree that magpies have a huge or unbalanced impact under songbird numbers, and certainly not more of an impact upon songbirds than cats or man.


Yes magpies will raid a nest for eggs on occasion, yes they will kill young birds and yes they can also kill adults, but no more so that they have done for hundreds of years.

Songbirds and eggs are not a primary source of food for magpies, decades of ornithology by much more learned folk than myself has borne this as a fact not opinion. Insects, carrion, and rodents have been found to be more common in the stomachs of dissected magpies from rural areas than nestlings or eggs. In urban areas various household scraps and other man provided food sources have overtaken eggs and nestlings in the stomachs of dissected magpies. Nestlings, eggs, and on rarer occasions, adult songbirds still get eaten though, but they are not a main food source.

A picture has been painted in this thread of a dawn chorus consisting of just the chatter of magpies if something is not done to control magpies. I say that is rubbish. If there were truth to that then the last few hundred years would have seen the magpie take over as they would have wiped out everything else before any person decided they were vermin.

But nature at it's purist does not work that way, it operates it's own system of checks and balances. Magpie numbers can never outgrow the various sources of food in their territories, it is simply impossible as they would die out themselves, the same as any other organism on this planet if it exhausts it's food source.

What should make for interesting reading is the population spreads and numbers in the 2007/11 bird atlas for Ireland and the UK. I have only a tiny part in that with my two 10km tetrads, but in my two I get to take in an urban area consisting of a city and many of it's housing estates and a totally rural area which ironiocally has a gun club within the boundaries of that tetrad.

The funny thing is that one area does not have a larger or healthier population of songbirds than the other, despite the rural tetrad having a gun club that pretty much shoots or traps magpies where possible.

The songbirds within the rural area breed fine, raise their young and so on. But the denisity of most songbird populations there are matched by those in the areas that have a healthy population of magpie and other corvids.

The answer is very simple. Nature has provided a way for the birds in the magpie rich area to maintain their numbers. That way is larger batches of eggs. The blue tits for example are laying three to four eggs more a batch in urban tetrad over the rural one where there has been culling of magpies for years and years. Same thing happens in raptor territories with many songbirds, as I get to see daily with a sparrowhawk nest which is partially in view from my bedroom window.

Another natural check upon magpie numbers are raptors and larger corvids. I have seen far too many magpie fall victim to raptors and hooded crow (also carrion crow in areas that have them) to think that it is not a natural check on their numbers. Juvenile to adults all fall to raptors and hooded crow seem quite partial to raiding magpie nest and also to the fledged juveniles.


I have waffled on now for a bit, but I ask myself do magpie have an impact upon songbird populations? I have to say that they do, but it is not an unnatural impact and not one that has placed any songbird at greater risk than man made impacts have done, nor has the magpie has a greater impact than threats that are introduced by man like the cat.

Nature follows it's own course when not impacted upon by man, and has always done so. The connection between Magpie and songbird has been going on long before man even became aware of it, and the hundreds, even thousands of years of that connection has not led to a magpie dawn chorus, and as such the magpie is not the species that would be the one most likely to the advent of a dawn chorus without song, the dubious honour of being the most likely cause of such a songless dawn is man.

waffled is right , you talk about magpies taking eggs/hatchlings as if it is a year round occurrence .
magpies have there young early in the nesting season for one reason ,they feed there young on eggs and young birds .

yes magpies raid nest ,every chance they get ,there handy pickings ,also they will come back until every chick is gone .

the magpie is on the rise our song bird numbers are falling ,in areas where vermin control is not carried out .

its so simple .

you contradict you self so often in your post ,personally i would not want to get to the stage where magpies out strip there food supply of eggs/nestlings.

Kess73

jwshooter wrote: »

waffled is right , you talk about magpies taking eggs/hatchlings as if it is a year round occurrence .
magpies have there young early in the nesting season for one reason ,they feed there young on eggs and young birds .

yes magpies raid nest ,every chance they get ,there handy pickings ,also they will come back until every chick is gone .

the magpie is on the rise our song bird numbers are falling ,in areas where vermin control is not carried out .

its so simple .

you contradict you self so often in your post ,personally i would not want to get to the stage where magpies out strip there food supply of eggs/nestlings.

Magpies won't out strip their food supply, anybody who thinks that they will is talking total rubbish and has no concept as to how a food chain works. I am currently with Birdwatch Ireland, and before I moved back here to Ireland I was involved with the BTO, and years of research have shown what you are saying to be rubbish.

You say that the songbirds are in decline in areas where vermin control is not carried out and that magpies are increasing in those areas. Well be specific about those areas so that I can report them and the people checking those tetrads can recheck their figures, and also so that the results of recently published studies on the effects of Great Spotted Woodpecker, Sparrowhawk, kestrel, Magpie, Jay and Carrion Crow/hooded crow on songbirds can be torn up and discarded. Also the studies on how the weather impacted heavily on songbird numbers in 2007, 2008 and winter 2009/10 must be rubbish too and it has been the evil magpies all along, as numbers could not have dropped because as a consequence of the previous two poor breedingseasons :rolleyes:

Weirdly enough in areas where songbird numbers have dropped so have the magpie numbers. Must have nothing to do with a predatory species not being able to sustain it's numbers without a prey species being present, after all you have claimed that the magpie numbers can increase with less prey about.

I am sure you can use google and look for yourself at the reports that have been issued by the BTO, RSPB, Birdwatch Ireland, and the JNCC which all rubbish your claims of magpies reducing songbird populations in the UK and Ireland outside of areas that have this wonderful "vermin" control.

You say it is so simple, so I repeat my request for these magical areas with the massive declines, because if what you are saying was true, then the songbird population in Ireland should be pretty much wiped out by now as magpies have been around a hell of a lot longer than the people involved in "vermin" control.


I will leave you with the below paragraph from Birdwatch Ireland with regards to the effect of magpie on smaller birds. It is only based on a few decades of study by people with a lot more knowledge on the subject than the average layperson. You can read it in full on the Birdwatchireland.ie site.




It is true that Magpies will take the eggs and the young of other birds. However this predation is restricted to a relatively short period, and for most of the year they take other foods. A recent survey on urban Magpies showed that eggs and young birds form a small percentage of their diet. It is probably fair to say that Magpies may sometimes be blamed for predation by domestic cats, squirrels or rats, and are often used as scapegoats when the real reason for a local decline in small birds is habitat destruction, the biggest threat of all to our birdlife. Detailed census work has shown no major decline in the populations of small birds that may be attributed to Magpies. A fluctuation in the numbers of small birds is more usually associated with habitat change or severe winters. Normally, predators do not control the numbers of their prey: the predator population cannot increase beyond a level which the prey can support. A partial predator such as the Magpie is unlikely to have any lasting effect on small birds and their hatchlings.

Mothman

Thread title changed to try reflect recent discussion. - Was "Nesting Robins"

jwshooter

where i live we have a great network of farmers ,hunters even a priest in enniscorthy town ,that use larson traps ,magpies grey crows are keeped well under control .

i spend some time in dublin ,its more common to see a magpie than a wren ,in parks and gardens.

you say vermin will not out strip there food supply this is very true ,one point you misses is the handy easily accessed food is gone first ..ie eggs/chicks in season .


you totally misses the point of the OP to get your point across , a magpie was raiding the nest of a robin in there garden .

as you know robins are fiercely territorial so the OP will not have the pleasure of seeing young robins this summer only happy fat little magpies .

Kess73

jwshooter wrote: »

where i live we have a great network of farmers ,hunters even a priest in enniscorthy town ,that use larson traps ,magpies grey crows are keeped well under control .

i spend some time in dublin ,its more common to see a magpie than a wren ,in parks and gardens.

you say vermin will not out strip there food supply this is very true ,one point you misses is the handy easily accessed food is gone first ..ie eggs/chicks in season .


you totally misses the point of the OP to get your point across , a magpie was raiding the nest of a robin in there garden .

as you know robins are fiercely territorial so the OP will not have the pleasure of seeing young robins this summer only happy fat little magpies .

It is more common to see a magpie than a wren anywhere in Ireland, but that has nothing at all to do with population numbers. It has to do with the size difference and the characteristics of each species. Wrens can be quite difficult to spot due to their size and their habit of staying low to the ground and generally under cover, whereas a magpie is a large gregarious bird.

I missed nothing with regards to the point of the OP, I questioned your comments about the magpie population being on an upward curve at the expense of the declining songbird populations, except, as you claim, in areas where "vermin" control is practised on magpies.

You still go on about the magpies wiping out all the chicks/egss during the breeding season despite all research done on the subject between 1967 and now saying that you are completely wrong and that the magpie has not attributed to anu major decline of songbirds in the 43 year period ion which the research took place.

I asked you to give me the locations of the areas that you claimed have seen big increases in magpies and huge decreases of songbirds, you could not do so despite earlier claiming it as some kind of fact.


I am also quite surprised to hear that such a great knowledgable group of "hunters", including a priest from Enniscorthy no less, seem to regard Larsen traps as an effective method when something like a ladder trap is more commonly used in areas with corvid problems.



As for the OP not having the pleasure of watching young robins, well neither you nor I can predict that. Nature will follow it's own course there, it is not always pretty but Robins(and other small birds) have co existed alongside robins in this country for hundreds of years and will do so for hundreds more if left unchecked by man.

BryanL

From the RSPB study
http://www.rspb.org.uk/Images/Predator%20Report_tcm9-177905.pdf
Magpie predation on songbirds

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.

from the same review
The first review (Newton 1993, 1998) considered 30
studies and found that predator removal resulted in
improved nest survival of prey in 23 of 27 studies (85%),
increased post-breeding population size (‘autumn
densities’) in 12 of 17 studies (71%), and increased
subsequent breeding numbers in 10 of 17 studies (59%).
A recent update of this review (Nordström 2003)
considered eight more studies, and found, unsurprisingly,
very similar results (improvements in nest survival,
post-breeding population and subsequent breeding
population sizes of 84%, 70% and 61%, respectively).
Thus, it appears that in more than half of all studies, the
prey populations concerned had been limited by predation,
and once predators were removed, prey populations rose.


But the RSPB are hardly going to go about asking people to kill birds are they?

jwshooter

as magpies are territorial we use larson traps as there easy to move ladder traps are a little big .

over 30 years ago my summer job was helping a gamekeeper feed and look after pheasants ,trapping magpies ,controlling vermin etc ,from that i have had a love of our wildlife all my life .

iv seen first hand the damage this lovely black and white bird can do ,from picking open the chest of a pheasant poult to picking the eyes out of a new born lamb .

you like them as there pretty like the fox ,you turn a blind eye to there murderous lifestyle .because it suites you .

you talk about human no intervention as if half the country has no one living in it ,there is very few animals/birds that are not affected by us .

were the top of the food chain for a reason .

Mothman

jw,
I realise you have not hinted or suggested this and the discussion has been about controlling rather than exterminating, but I'm wondering if you feel that Magpie has a place in the Irish countryside?

jwshooter

Mothman wrote: »

jw,
I realise you have not hinted or suggested this and the discussion has been about controlling rather than exterminating, but I'm wondering if you feel that Magpie has a place in the Irish countryside?

Mothman .

like i said i fed crows and jays during the winter ,i had to run them some days as they were keeping the small birds of the feeders over the 5 weeks of frost and snow .

i had a magpie in my larson trap this morning ,i know there is a clutch of them and grey crows in the same area i will leave it for a week and then move it .

we will never exterminate them or would i want to ,like foxes i would shoot a lot every year and cull a lot of deer .

management is a word kess and others struggle with , some of us have live in the real world where man has to take control for the good of the ecosystem.

do u guys have the same feelings for rats or are they not pretty enough

John_Rambo

jwshooter wrote: »

you totally misses the point of the OP to get your point across , a magpie was raiding the nest of a robin in there garden.

Nope. You did.

You also misquoted me on another forum and what you likened me to and your solution for me was really uncalled for. However, I feel you may have missunderstood me. No point in being enemies with a man with a gun!

I asked if the magpies would harm it, they haven't (yet), the robins are doing fine, flying in and out of the nest. I don't know if there are any eggs in there as I am afraid to scare them off. Gun dog dutifully keeping the cats away.

The dawn chorus is all songbirds. The magpies don't seem to join in, but there is an awfull lot of them in the area. People from both sides of the arguent, thanks for your views, is there any way I can discourage them without discouraging the rest of my garden wildlife?

ytpe2r5bxkn0c1

I really can't believe what I have been reading here for the past couple of days. Some people still believe magpies are evil birds wiping out songbirds. They do not. It has been studied over and over and stated over and over but still the falacy persists. Red Squirrels take eggs and chicks. Do we demonise them?
Then we have the twisted view of diversity where the hunting fraternity seem to think that they alone are preserving our wildlife. Only as a side affect to their manageing species so they will have more to hunt. I'm not against hunting but don't make unfounded claims. You can't preserve our Bio-diversity by trapping or shooting some species so you will have more of another species to shoot.
I'm agast at a Nature & Birdwatching forum referring to Magpies and Foxes as vermin!
Maybe it's the rain but I dispaired when I read the posts on this thread.

Feargal as Luimneach

BryanL wrote: »

From the RSPB study
http://www.rspb.org.uk/Images/Predator%20Report_tcm9-177905.pdf
Magpie predation on songbirds

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.

from the same review
The first review (Newton 1993, 1998) considered 30
studies and found that predator removal resulted in
improved nest survival of prey in 23 of 27 studies (85%),
increased post-breeding population size (‘autumn
densities’) in 12 of 17 studies (71%), and increased
subsequent breeding numbers in 10 of 17 studies (59%).
A recent update of this review (Nordström 2003)
considered eight more studies, and found, unsurprisingly,
very similar results (improvements in nest survival,
post-breeding population and subsequent breeding
population sizes of 84%, 70% and 61%, respectively).
Thus, it appears that in more than half of all studies, the
prey populations concerned had been limited by predation,
and once predators were removed, prey populations rose.


But the RSPB are hardly going to go about asking people to kill birds are they?

Wrong, The RSPB are 100% behind the eradication of the non-native Ruddy duck in the UK (because the Ruddy duck are hybridizing with endangered white headed duck in spain).
The RSPB are also concerned with the appearance of Eagle owls in the UK. They are though to be breeding from escaped birds not wild birds from continental Europe. If they are shown to have an negative impact on native UK wildlife they will advocate eradication. More research in needed first on the course they will take.

jwshooter

i dont think Bryanl was talking about eagle owls BTW.

Feargal as Luimneach

jwshooter wrote: »

i dont think Bryanl was talking about eagle owls BTW.

"But the RSPB are hardly going to go about asking people to kill birds are they?"
I was answering his question by giving examples:D The RSPB will cull birds if deemed necessary.