16
Dec
14

New study suggests that killing crows is mostly pointless, most of the time

crows in trap Walter BaxterYesterday saw the publication of a new scientific research paper entitled: A review of the impacts of corvids on bird productivity and abundance. The paper is available for free download here.

If you want to skip over the technical details, the authors have helpfully issued a press release which provides a more general overview for the more casual reader. It reads as follows:

A MURDER OF CROWS?

They steal, raid nests, and keep the company of witches. But the unpopular crow may not be as big a menace as people think.

A new study has found that crows – along with their avian cousins the magpie and the raven – have surprisingly little impact on the abundance of other bird species.

Collectively known as corvids, these birds are in fact being menaced by mankind in the mistaken belief that removing them is good for conservation.

The new study was led by researchers at the University of Cape Town and published this week in the leading ornithological journal Ibis. It found that in the vast majority of cases (82 percent), corvids had no impact at all on their potential prey species.

“Many nature lovers have been distressed to witness a crow or magpie raiding the nests of their beloved garden songbirds, stealing their eggs or eating their defenceless chicks,” said study co-author Dr Arjun Amar from the Percy FitzPatrick Institute for Ornithology. “Although this predation is entirely natural, these observations can be upsetting to witness and often leave people wondering if these predators might be reducing bird numbers.”

“However, our global review suggests that we should be cautious before jumping to conclusions over the impacts these species may have. Just because a predator eats something occasionally does not always mean that they have an impact,” Dr Amar said.

The study, the first of its kind, reviewed all published evidence on whether predation by corvids actually reduces the overall breeding performance of birds or, more importantly from a conservation perspective, reduces their numbers. Data were collated from 42 studies of corvid predation conducted across the globe over the last sixty years.

Not only were corvids unlikely to have any impact on their potential prey species, if there was an impact it most often affected the breeding success of the prey species rather their subsequent numbers. Half of cases found that corvids reduced breeding success whereas less than 10% of cases found that they reduced prey numbers in the long term.

“These results have big implications for the likely benefits of corvid control,” Dr Amar said. “They suggest that killing corvids will be of most benefit to those interested in gamebird shooting rather than conservationists.” He added: “Bird hunters are usually most interested in increasing numbers of birds available to shoot immediately after the breeding season and this appears to be where corvids have most impact”. “Conservationists on the other hand, are usually interested in increasing a species population size and our results suggest that only in a very few cases did corvids have an influence on this aspect of their prey,” Dr Amar said.

The review analysed the impact of six corvid species on a variety of prey species including gamebirds, songbirds, waders, herons, cranes, sea birds, waterfowl and raptors. The 42 studies incorporated into the review included 326 cases of corvid – bird prey interaction Most of the data stemmed from field research in the UK, France and the United States. The impacts were determined partly by comparing bird counts before and after corvids were either removed or their numbers reduced.

The review also found large differences between the impacts of crows, historically considered the most ‘cunning’ corvid, and magpies which are sometimes killed by home owners hoping to protect songbirds in their gardens. Crow species were six times more likely to have an impact on bird prey species than Magpies.

Mistaken assumptions about corvid predation were possibly explained by the birds’ diurnal nature and the fact that they are conspicuous nest predators: “Their importance in prey population regulation is often assumed prior to any assessment of the evidence,” the study warned.

Chrissie Madden, the lead author on the paper, hoped that the review would challenge the perception that all corvids were bad, thereby preventing needless killing: “Our results suggest that this is a mistaken belief and that generally speaking people would be wasting their time killing corvids to increase bird numbers”.

“Overall therefore, our study points to the fact that we are often too quick to jump to the conclusion that crows and magpies may be the cause of bird population declines,” she said.

END

SNH logo 2The paper itself is an interesting bit of science, but of more interest (to us at least) is the potential application of the research results. Basically, this review paper has shown that in the vast majority of cases, corvids (including crows and ravens) have little effect on their prey populations, and thus this raises an important question about the validity (and legality) of Government-issued General Licences which allow the mass killing of corvids, supposedly for the purposes of ‘conserving wild birds’.

General Licences have long been an issue of concern to conservationists, and we have blogged about this a lot (e.g. see here & scroll down through the posts and links). General Licences are routinely used by gamekeepers and land managers for the largely unregulated practice of killing so-called ‘pest’ species, especially corvids, in Larsen traps, clam traps and crow cage traps, or by shooting them. However, General Licences are not permitted to be used to kill ‘pest’ species for the purposes of protecting surplus stocks of gamebirds, even though that is exactly what gamekeepers have been doing, although they don’t admit to that – they simply claim they are ‘controlling vermin’ to protect wild birds such as waders.

How will SNH deal with the results of this latest study, given the overwhelming evidence that corvid predation isn’t having a significant impact on wild bird species in the majority of cases?

Don’t expect a quick response from SNH. We are still waiting for them to deal with other concerns that have been raised about the use of General Licences, some of which were raised in a publication dating back 15 years:

dick-stronach-1999-use-abuse-misuse-of-crow-traps

Interestingly, SNH has recently announced that their suite of 2015 General Licences will shortly (this week) be published on their website, WITHOUT conducting a public consultation and WITHOUT any substantive changes to their 2014 licences. Robbie Kernahan (SNH licensing dept) said:

From our previous consultations and discussions on the GL suite, I think we have a good understanding of the key issues and your outstanding concerns relating to General Licences“.

So that’s ok then. SNH understands the key issues and concerns but has decided not to address them. Brilliant.

Although, they are apparently addressing one aspect of trap use and have been conducting a questionnaire survey of trap-users (see here). As we blogged at the time, asking trap-users for a truthful account of their activities is, frankly, ridiculous. We all saw quite graphically last week, with the conviction of gamekeeper George Mutch, how some of these trap-users are operating.

We’ll be re-visiting this topic in the New Year.

Photo of trapped corvids by Walter Baxter

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47 Responses to “New study suggests that killing crows is mostly pointless, most of the time”


  1. 1 Nigel Raby
    December 16, 2014 at 3:11 pm

    Killing crows is probably mostly pointless because they are killed by mostly pointless people!

  2. 2 crypticmirror
    December 16, 2014 at 3:43 pm

    Can’t say I haven’t suspected this for quite some time, nice to have some science backing up my anecdata though. To people retweeting this, remember to copy in @TheSNP so the Scottish Government sees this, please.

  3. December 16, 2014 at 4:08 pm

    I’ve thought this about crows and other predator killings for a long time. Just adds proof to my thoughts on how stupid the folks that kill predators are. Some time ago I heard a comment from a gamekeeper about goshawks. He said, “Goshawks are evil, they kill for pleasure!” Ironic or what?

  4. 6 nirofo
    December 16, 2014 at 4:41 pm

    I’ve been saying it for years, all that the killing of the crows does is deny other birds the use of their old nests. Since the use of the Larson traps became common practice in the far north the Merlins have changed their nesting habits, before the larson traps the majority of the Merlin nests we found up here were in old Hoodie Crow nests, many other old hoodie nests contained Long-eared Owls,Tawny Owls and Kestrels. Now there are very few old hoodie nests about and the Merlins nest on the banks and braes in what’s left of the long heather, years of relentless muir burn have all but destroyed it.

    Just to show the extreme persecution the crows face at the hands of the gamekeepers, I have a photo taken of a gibbet containing 56 Hooded Crows, why the keepers think it’s good to kill so many and feel the need to show so much needless death by hanging it for all to see beggars belief, it shows the level of their mentality and proves they have little thought for any wildlife other than the gamebirds they hold in so much reverance.

    I have several photos of keepers gibbets etc, showing the amount of senseless killing they are capable of, pity I can’t post them here.

  5. 7 Marco McGinty
    December 16, 2014 at 5:30 pm

    I haven’t simply thought that this was the case, I knew it was the case. It’s all fairly simple and straightforward – if corvids were having the impact that some people believed, there would have been hundreds, if not thousands, of extinctions in the past few centuries, and we would be hearing of extinctions far more regularly than we do. For instance, how many species of songbird or wader has become extinct in the UK since records began, and were any of these extinctions as a result of corvid impacts? No, didn’t think so. The fact that this did not occur (and does not occur) is evidence that the various species of corvid found globally, all play a vital part in the natural balance of each ecosystem. But then again, anyone with any sense would have figured that out.

    However, despite being valuable scientific evidence for true conservationists, the report will be completely ignored by the liars of the shooting industry.

    I agree that SNH should now accept the findings of this report, but as they are so keen to appease their masters in the shooting industry, and have no real interest in the welfare and future prospects of Scotland’s wildlife, they will most probably ignore the report as well.

  6. 8 Chris
    December 16, 2014 at 8:16 pm

    I’m sorry, but I cannot agree with this entirely. I am a falconer and environmentalist, so I understand the worry about the misuse of crow traps, but I have seen for myself the difference in a suburban area on song bird populations after magpie numbers were reduced. Raptors rely on their prey species entirely, as top predators their numbers are suppressed if they reduce prey populations too much. Corvids do not rely on chicks and nests, but will take what they can when it is available. When bird populations become suppressed (for what ever reason) they simply change their diet to something else.

    This report is not science, it is an examination of previous statistics from too large an area and over too long a timescale to give findings that are reliable enough.

    We need to be working first on the large scale of environmental damage and degradation man has, and continues to cause. The current balance of most global eco systems is anything but natural.

    And for the record, I’m not a great fan of driven shooting either, If it was banned I would loose no sleep,but it is a fact of life we have to live with.

  7. 9 paul griezel
    December 16, 2014 at 8:42 pm

    ignorance is only on all the comments I have read above. where I live we have keepered areas and some valleys between where there is no keepering done. every year I can see the difference in lapwing broods between the two and witness carnage from the many pairs of carrions on not just the lapwing numbers but lots of other ground nesting birds too. interestingly on the unkeepered ground there is plenty of old carrion nests and the merlins still nest on the ground…that’s all of the 7 nests I sometimes sit and watch from the roads! come on, the boot would be on the other foot if they were eating harrier eggs or ospreys for that matter of which I have seen footage on the web. there was outrage about it then!

    • 10 nirofo
      December 17, 2014 at 2:00 am

      Makes you wonder how all the little birdies managed to survive for hundreds of thousands of years before the gamekeepers came along to help them out !!!

    • 11 Marco McGinty
      December 17, 2014 at 12:05 pm

      Paul, as you have made the sweeping generalisation that we are ignorant to the situation, I would be most grateful if you would provide some evidence for your belief, and not some anecdotal example.

      The fact of the matter is that you are wrong, and the only ignorance displayed is by you and those others that refuse to accept in a natural balance. As mentioned here (and on many other pages on this site), corvids have managed to co-exist with all other forms of nature for millennia, so why has this “conflict” only been an issue since the advent of game shooting? To my knowledge, there has never been an extinction, or near extinction of a species, solely attributed to corvids. Would you be able to provide an explanation for that?

      On your point about the predation of osprey or harrier eggs, if the situations were reversed, the majority of people on here would accept that as a simple act of nature, and many have made such comments on this site, on this very subject. I’ll gather that you haven’t read the report, or will ever consider doing so, and that you have even ignored the synopsis provided above.

      On the perceived outrage about video footage of harrier and osprey eggs being taken by corvids, would you please provide links to the footage and comments? However, if this is the case, then you would have to consider where these comments originate from. Do they come from experienced and knowledgeable conservationists, naturalists or environmentalists, or are they the opinions of less experienced individuals? There are people out there that believe the natural world is all about fluffy bunnies and cute little animals, and is a world where nothing gets eaten.

      To finish, I have a question for you; Would you be in favour of a cull of waders and songbirds to protect rare or scarce invertebrates?

      • 12 Paul griezel
        December 17, 2014 at 4:11 pm

        Marco,
        No need to get so shirty about this, being patronising just annoys people!
        You say corvids have managed to co exist with nature for millennia. Where I live in the unkeeperd valleys there is only an odd carrion all winter. In the spring they turn up in flocks. Maybe in the most recent years the corvid numbers have grown because of easy food supply created by humans. Carrions nest in nearly every tree where my parents live on the outskirts of a town, is this because they find food easily from people’s gardens, waste tips ? I have even seen them eating chips off the floor in many towns. Maybe this is why they need to be controlled because in the last millennia things have changed so much, was there as many humans creating new surroundings?
        I will find the footage of the osprey egg being taken by a carrion and post the link.
        I would be in favour of a cull on waders and song birds to protect invertebrates if there was sufficient numbers of the predators, in my opinion it’s all about balance- remove one predator if the pray is scarce
        To finish I have a question for you; would you be happy to live in a home that is infested with rats or eat from a restaurant with a rat problem? Or would yo get them controlled by a pest controller? Is it simply that this would be different?

        • 13 Marco McGinty
          December 17, 2014 at 9:49 pm

          Again, I will ask for some evidence on why we are all being ignorant to the situation, and not some anecdotal evidence.

          I stated that corvids have managed to exist with songbirds, waders, etc for millennia, because it is an incontrovertible fact, and not a supposition. If you can provide evidence to the contrary, then it would be much appreciated.

          You then go on to portray the situation in your area, and you may well have a thorough knowledge of your own locality, but your understanding of the bigger picture appears to be wanting in some respects. For example, you have suggested that “Carrions nest in nearly every tree where my parents live”, which I suspect is a slight exaggeration (or trees are very sparse), and your belief that as a result of the excess waste produced by humans, corvids numbers have multiplied by a considerable number, and therefore need to be controlled.

          I have a problem with such beliefs. If the corvids have increased because they are finding it easy to obtain food from humans, then surely they can’t be having such a negative impact on songbirds and waders in the countryside? However, you are correct in your assertion that humans are part of the problem, but that is mainly down to habitat loss. Recreating habitats should be the way forward, not killing because of unfounded and unscientific beliefs.

          If you can find the link to the predation of the Osprey egg, that would be appreciated.

          In relation to your statement that waders or songbirds should be culled to protect invertebrates, well, I find that very strange. You support your claim by purporting to believe in natural balance, yet at the same time you suggest that predators should be removed! That is frankly absurd. Predators are part of the natural balance, and by removing just one predatory species, you are creating an imbalance. But back to your statement that you “would be in favour of a cull on waders and song birds to protect invertebrates if there was sufficient numbers of the predators”, and I will point you to a simple fact. Grouse moors are managed to attain artificially high numbers, at the expense of a wide variety of species, and it is a similar situation in areas that rear the non-native pheasant, with a large number of native species being killed to support this regime. If you support a natural balance, then you cannot possibly offer your support to the monoculture of driven grouse moors, or the annual introduction of millions of non-native pheasants, so something is clearly wrong with your beliefs and statements.

          As for your nonsensical question, I will try my utmost to provide you with an answer, however I have no idea of the relevance of this question. Both the Brown Rat and Black Rat are not native species to the British Isles, which again adds to my question on relevance, but it is highly unlikely that I would ever find myself living in a rat-infested home, and nor would most people living in the developed world, but in the interests of answering your question, I will say no, mainly because a home filled with non-native species would eventually have a localised impact on native wildlife, much the same as the release of millions of pheasants into the countryside every year. As for the restaurant query, if I knew that a restaurant was infested by rats, no, I would not eat there, but the issue of the pest-controller would be one for environmental health officers. I honestly do not believe that a member of the public can request that a pest controller carry out work at in independent businesses premises, without any proof of a problem. As stated, a nonsensical and utterly irrelevant question.

  8. 14 crypticmirror
    December 16, 2014 at 10:17 pm

    I’ve seen a few mentions of this on twitter from the farming lobby saying they need to kill crows to protect chickens and sheep at lambing times. Does anyone have any advice on how to properly rebut those accusations using moderate language?

    • 15 nirofo
      December 17, 2014 at 2:02 am

      Yes, use moderate swear words, most of them are in the dictionary.

      • 16 crypticmirror
        December 18, 2014 at 5:23 pm

        While I certainly would use those in private, I’ve found that for the purposes of rebutting an argument civil language and actual logic works a lot better. Even if the individual in question does not change, at least I’ll have had a chance of getting a few onlookers to have a bit of a rethink. Use sweary words and I’m just another ranting idiot the like of which the world has no shortage of and will be utterly ignored. I know that it is fashionable right now to scream “Tone Argument” at that line in thinking, and to deliver a load of abuse for suggesting it, but those guys are just ranting idiots the like of which the world has no shortage of and I feel I can safely ignore them utterly and continue with reasoned arguments. So, I ask again, does anyone have any moderate-language counter points to the claims of killing chickens and blinding sheep?

        • 17 keen birder
          December 19, 2014 at 7:04 am

          I think you would use some sweary words if you came across one of your own sheep blinded by a carrion crow, or would you softly say, aw its only nature, poor little crows they are only doing what comes naturally.

          • 18 crypticmirror
            December 19, 2014 at 1:06 pm

            Thank you for the condescension. However I did grow up in a farming area and while I was too young and foolish to listen to much of the conversations off the farmers, I do remember a chorus of “yer havering” and “dinnae talk daft, man” from the greybeards with the flat bunnets whenever anyone would complain about livestock losses. I’ll admit that I do now wish that I’d listened to why the individuals who were havering were talking daft about losses to crows, ravens, and foxes, but I was more concerned about the new GTi’s in the pub carpark (and, even more embarrassingly, the spotty little oiks driving them who, for some reason, I thought were cool and good looking. Ah, the sins of youth) than farming at that age. I do wish I’d paid more attention to those greybeards.

            • 19 keen birder
              December 19, 2014 at 5:33 pm

              well we probably would not agree with what some of the grey beards probably did, at least the larsen trap has done away with any excuse of having to poison crows, they can be incredibly successful.
              And the modern high powered lamp and even night vision sights, for foxes again no excuse to resorting to the old ways of strychnine. Thankfully its been banned and cant now be obtained, I flushed my last bottle down the toilet,,best spot for it, it was a deadly way of eliminating moles, but could sadly get into the wrong hands, poor old one eye,, im away now to hay them, take care now.

  9. 20 keen birder
    December 16, 2014 at 10:56 pm

    Does that mean I can start egg collecting then, as it will not have any effect on bird numbers.?
    Of course crows can have an effect on other birds breeding success, which if they are successful will mean more birds, especially lapwing and curlew which are particularly vulnerable and need every bit of help they can have. Carrions can be a pest at lambing time as well, they can take eyes out of sheep when down lambing, I had this on an ewe, it now has 1 eye, its lamb later died, you can try scaring and disturbing but if they are hungry they will be back, and lambing inside is not an option for most sheep keepers .
    Larsen traps are often set close to a crow nest, so the old nest will still be there, theres one hell of a lot of old crow nests about. Keepers gibbets are nearly a thing of the past, ive only seen 1, about 38 years ago.
    People still seem to hang moles up on barbed wire fences, strange ,, be better to push them into the ground and have the benefit of their bit of fertilizer from their bodies.

    • 21 Marco McGinty
      December 17, 2014 at 12:54 am

      You don’t seem to have managed to grasp the science behind the report.

      If you start egg collecting, then that is an additional and unnecessary pressure placed on any species of bird, and as corvids, waders, songbirds, etc have happily co-existed for millennia, then it is quite evident that they do not have any adverse impact on any other species. You also appear to be following the shooting industry mantra that by controlling corvids, other species will benefit. This is of course true, but you are creating an imbalance in nature by doing so. Would you promote a system in conservation that demands that songbirds be killed in huge numbers to aid rare or scarce invertebrate species?

      As for sheep, if anyone imposes an artificially high population of any species, then you have to expect that you will lose some to nature, whether that be corvids, raptors or mammals, and you must also accept that the large areas of countryside required for sheep farming, is detrimental to a massive range of native, wild species.

      • 22 keen birder
        December 17, 2014 at 7:51 pm

        hi Marco, yes you are right, we need more people like you, who understand the system, I can see both side of the fence, man has really altered things big style really for nature, crows just want an easy meal, a change of diet at the end of a long winter, a nice egg or whatever,you can understand them, for doing that. I often wonder what nature numbers were like before shooting started, say 600 years ago.
        Things are in a bad way now, curlews and lapwings have just about gone, very few breeding now, we all know why, combination of reasons. keep up the good work.

  10. December 16, 2014 at 11:21 pm

    Thanks for the mention of our 1999 report blogmeister…which of course wasn’t about whether crow cage traps were a useful way of protecting birds from crows..but was a clear demonstration of how destructive the traps are to a wide range of protected species. Completed ignored by those who licence these awful machines [which are outlawed in several european countries due to their non-selective trapping – seen as contravening the EC Wild Birds Directive]. The fact remains that to some crow cage users these are hawk traps, not crow traps.

    Also..some of the old hands here may remember this paper – also, completely ignored by those in authority – by David Houston in 1977..which exonerated hooded crows from being serious sheep killers in Argyll.

    But hey..no one on shooting estates wants to hear the truth about these things..after all , they are the guardians of the countryside with generations of experience in vermin control. So they cant be mistaken …can they????

  11. 25 Jimmy
    December 17, 2014 at 12:08 am

    Corvid numbers appear to be little impacted by anything thats thrown at them so it doesn’t really matter if they are protected or not. I wouldn’t worry about them being on the general licence for example

  12. December 17, 2014 at 11:59 am

    Crows and ravens are often described by those researching these birds as the ‘feathered ape’ due to their high intelligence. The stress and suffering that these birds must go through during capture, especially when they are forced to share the cage with other trapped corvids, must be tremendous. The image of so many corvids in a single crow cage trap as above suggests strongly that the cage isn’t being checked regularly as the law requires. If anybody ever sees such high numbers of birds in a crow cage trap then they should report it immediately to the RSPCA/SSPCA. It also suggests that the keeper is sloppy in his work and so it may be worth looking around for snares which may not also be being checked and consequently animals dyeing a slow and painful death.

    Let us also not forget the fait of captured corvids which have been filmed on more than one occasion being beaten to death with sticks and stamped on. The Scottish charity Onekind captured such an event at Glenlochy Estate where an individual was filmed entering a cage with a dozen crows in it, picking up a stick and repeatedly beating the crows until they stopped moving. He then left four crows in the cage as ‘calling’ or ‘decoy’ birds with unsuitable perching or shelter for all four corvids. Although a number of regulations were broken in relation to the operating of the crow cage trap there was no arrest, not even an official warning.

    As we write here now, PR is aware of crow traps actually in operation with crows being used as decoys. They are situated on grouse moors, on tops of hills in Scotland and these birds will be forced to endure the extremes of the winter weather as they unknowingly attract others into the trap. If anybody has seen the pitiful little shelters in these traps you can understand how these highly intelligent and sentient birds will suffer over the coming weeks with the freezing days and nights as well as the stormy gales and snow ahead of them.

    • 27 keen birder
      December 19, 2014 at 9:21 am

      killing crows like that is totally not necessary, simply use a salmon landing net, catch each one, humanely dispatch it, place in bag away from sight of others,and have good food in the trap, for 2 reasons, to feed the decoys, and attract others, if not then they will not catch crows. The crows need a shelter which is a legal requirement, the weather in the cage is probably more sheltered than outside, crows roost in trees with the wind and rain ,snow and frost, they are used to it, the captive birds are not there permanantly, fresh birds take their place. I can see the day coming when these traps will be outlawed. why not just ban everything then, even fishing is like water boarding fish if you think about a salmon being pulled in against the water,, and what about the stress of sheep auctions,, my poor lambs having nothing to eat for over 24hrs and being transported to Birmingham on a lorry containing 600, to a death in a hal hal abotoir , having throats cut.. or the turkeys being killed in vast numbers in the last few days, all to feed the nation, think about that,,, or the tons of Sea fish left in a heap to die of no oxygen in the bottom of a trawler, could go on and on,,

  13. 28 Een Historicus
    December 17, 2014 at 12:19 pm

    Very happy with this study. I like crows, ravens and magpies. In the orchard behind my apartment a family of 7 magpies lived last summer. And YES! We still have songbirds like the yellow hammer and redstart.

    I vote for redefining the definition of ´pest´. Humans are obviously more harmful for nature than any animal will ever be. Unless we control the people who play God or Mother Nature, paradise is lost forever. Here in Germany a professor published a very good book about ravens and their relatives. He battles for the species for decades. Interestingly shooting crows, magpies, rooks etc. only makes a population younger, because not a single animal can reach it´s maximum age. They react by re-procreate faster. So shooting them is just as useless as shooting foxes.
    The professor once had a pet raven, which was shot by a farmer, only because it was a raven.

    Carrioncrows and magpies eat of course chicks of rare birds-species. The reason waders, but also harriers are doing bad in the Netherlands is in 1st place the intensive farming and NOT crows, because a HEALTHY population of lapwings etc. can deal with this. But that´s the problem. What population is still healthy? We can´t step back in pre-historic times, but we can use our common sense: Do we want natural, wild nature as far as possible, or do we all quit and make ´parks´, where only the species may live, that we, humans like?

  14. 29 Merlin
    December 17, 2014 at 11:15 pm

    the people who are killing corvids are also killing the raptor species that kill corvids, its these idiots that are the bloody problem!
    sparrowhawks kill jays, it stops jays from robbing their eggs, this means jays generally avoid arees were sparrowhawks nest and this in turn means jays have less suitable nesting areas, meaning less breeding pairs of jays, buzzards in the same way surpress jays magpies, carrion crows and sparrowhawks, for goshawks include all those already mention for buzzards and include buzzards as well.
    kill corvids on an estate surrounded by other estates and you will surpress their numbers. but on an estate surrounded by public parks and your not going to effect the population, here you need raptors.
    its very similar to the problem in the sixties when the government paid for wood pigeons to be controlled, the more that were shot the more survived the winter, they didnt starve from shortage of food

  15. 30 Tim
    December 18, 2014 at 6:58 pm

    its the blind leading the blind on here. obviously none of you have seen a sheep stuck in a wet hole or struggling with a birth with its eyes pecked out. I’ve seen this many times and I have also come across large numbers of pecked eggs. you lot are just as bad as the keepers, picking your favorite species over all others is not conservation. if a lapwing had a hooked beak it would be a different story.

    • 31 merlin
      December 18, 2014 at 9:12 pm

      Hang on a minute, whose choosing which species to conserve here, grouse moor keepers are killing Corvids, raptors, mustelids, mountain Hares foxes and more just so they can shoot more grouse, were saying leave them alone. Lapwings are just fortunate GWCT haven’t found anything suggesting they might disturb a Grouse’s sleep pattern or they’d be extinct by now! Just because these groups have wildlife and conservation in their titles doesn’t actually mean they give a damn about it
      While you mention pecked eggs lets mention the chicken farmer who applied for a license to kill buzzards, I’ve been to third world countries were they have managed to cover fields of crops and orchards with netting in order to protect them yet this seems too difficult over here or are they just damn lazy! , same with the guy who claims they are killing his pheasant poults, blind leading the blind, I would say that was when gamekeepers used to have a gibbet to show the land owners “ there you are boss look at all the creatures I’ve killed just so you can shoot more birds” no conservation isn’t killing everything either.

    • 32 keen birder
      December 18, 2014 at 10:00 pm

      Ive browsed at the report, I see at the bottom of page 7, Bolton et al 2007, showed a 2 fold increase,, Fletcher 2010 found that a 3 fold increase in breeding success of birds, it went on and on about increasing breeding success after removal of some of the crows and red foxes,, its pretty obvious to me.
      They certainly will not do any good for the likes of lapwing etc, you only need to watch nesting lapwing to see how harried they are when a crow comes near, then its mate can sneak in and grab an egg, I know its just nature, but why sit back and accept it when it can be legally prevented, I think lapwing could become extinct as a breeding bird, because of a lack of suitable habitat and predation, they have gone from most of Cumbria, supporting crows will not do them any favours, . The crow cages are sometimes cruel if not looked after, but the resident birds in there must have good food and water or they will die, and then no crow will go in, and there must be good bait in the cage or it will not catch much, the crows in there are guaranteed food, which in the wild maybe they might struggle to find, any buzzards caught are released, I have let out many a one from mine. Anyone doing otherwise deserves all they get.

      • 33 nirofo
        December 19, 2014 at 2:22 am

        There used to be Lapwings and other waders nesting almost everywhere on the moorland edges and meadows, now you’re lucky to find any, there were always plenty of crows about too, far more than there are today, and although they predated the chicks and eggs of other birds as they have always done for millennia, they didn’t seem to have too much impact on their overall breeding success. The serious decline of these moorland and meadow breeding wader species seemed to coincide when the handing out of grants and subsidies willy-nilly to landowners and farmers for land drainage schemes and so-called land improvement became freely available, improvement for what? Many prime nesting and feeding sites were ruined forever during this period for no other reason than to obtain the grants, making sure the birds would never come back again. The only thing that was improved was the landowners bank balance at the expense of the tax payer.

        The keepers can use all the excuses they want to justify the killing of corvids and other predators, the fact is they’ll kill anything that presents any kind of threat to their so-called game birds regardless of whether they are crows or protected species.

        • 34 crypticmirror
          December 19, 2014 at 1:08 pm

          I agree, field drainage has done for them. Several prime nesting spots in the Irvine valley were drained during the 80s and the birds just vanished. Whether it was the disturbance of the drainage systems being installed (during the nesting period too) or whether it just ruined the habitat in general I do not not know. All I know is they are gone.

      • 35 Marco McGinty
        December 19, 2014 at 7:12 pm

        Keen birder, The authors of the report have tried to demonstrate that corvid removal on its own does not have any impact on prey species, so cherry-picking an excerpt from the report that involved predation from corvids AND additional species, is counterintuitive. Obviously, the wholesale removal of predators will benefit prey species, but that will surely prove to be detrimental to the ecology.

        When some species decline in correlation with an increase in some predator species, it is easy for those with vested interests to jump to the wrong conclusions. If corvids and raptors were having such a major impact on species, would it be possible for you (or anyone else) to offer a suggestion as to the huge population increases in a considerable number of passerine species?

        However, the main problem facing Lapwings is habitat loss. Part of my local patch was a brownfield site which used to hold at least 12 pairs of Lapwings during its peak, but sadly they are all gone now. The reasons? Mostly habitat loss. Much of the area has been retaken by industry, and the remaining section has seen major encroachment by Sea-buckthorn. Alongside the changes to the habitat, disturbance by dog walkers was also a problem. Lapwings also bred at a nearby field that used to flood regularly, and this small area of wetland used to hold many nesting pairs of Mallards. Wintering Gadwall were regular, and I am convinced that this species would have bred in the near future, however the site is owned by an energy company, and some bright spark from this organisation decided to restructure and re-profiled the “pond”, in the hope that Little Ringed Plovers would start nesting. Little Ringed Plovers are a very rare/scarce migrant in the county, so why they decided on this species, I have no idea, but I have an inkling that must have watched Springwatch that year! The resultant changes to this small section of wetland were huge – Mallards stop breeding, Gadwall stopped wintering, and the Lapwings also disappeared. Mallards have since re-colonised, but only a fraction of what was once there.

        There could have been a decades-long, zero-tolerance approach to all predators in a fifty mile radius of the site, but the Lapwings would still have ceased breeding, and the predator control programme would have achieved nothing for the local Lapwing population.

        Now onto the issue of traps. Some users may follow the required guidelines for use, but there are others that do not. That is patently clear. But I must take you to task on one of your statements. You clearly believe that crows are posing a massive problem with other wild bird populations, as well as livestock, yet you provided the following;

        ” the crows in there are guaranteed food, which in the wild maybe they might struggle to find”

        You do realise that you have contradicted yourself with that very statement? So which is it? Are crows rampaging through the countryside eating everything in their way, and on the verge of generating extinction after extinction, or are they struggling to find food?

        • 36 keen birder
          December 19, 2014 at 10:27 pm

          Hi Marco, you ought to be a lawyer, you have all the answers lol. the crows are not doing either or any of what you are suggesting, I dont think the crows are a massive problem, did I say they were,? maybe I infferred they were, I meant predation generally, , theres a huge increase in all predators in our area, mainly buzzard, Badger, and more foxes. Earlier articles on this blog talked about how crows had to endure the weather in cages, with small shelters, in a crow trap I meant they will be able to eat every day, theres a great pile of road kill in there, they are well looked after,its in the trappers interest to do so, (failure to do this is illegal and will not catch any crows,) I meant in times of hard weather, the ones in the wild could be struggling to find food, though ive not seen any starving crows , when other creatures start dying of cold, the crows can benefit by feeding on their corpses, am I contradicting myself?, you get the drift, .
          Habitat is everything, without it there never will be birds of any sort. just looked up in, the breeding birds of Cumbria Atlas 97-2001,lapwing in 2001 approx 11500 pairs, and carrions 33000 breeding pairs,, whatever man does to them, they will fill in from unkeepered areas, they are a very successful bird, pity the lapwing wasnt as such. Theres no doubt, that the huge changes in farming methods have destroyed many suitable habitats not only for lapwing but nearly all farmland birds, .
          My point is, crow common,, lapwing rare, so where possible give lapwing every chance of rearing a brood by legal removal of crow,, I dont think this is upsetting the balance of nature.
          It could maybe be argued that I have done that by us putting up over 120 barn owl nest boxes.
          We urgently need more habitat, I think the tide has turned, theres a tremendous amount of hardwood planting gone on in the last few years,. I would like to see the rspb buy a large farm in the North, and do what they have done at Hope farm in Cambridgeshire .

          • 37 Marco McGinty
            December 20, 2014 at 12:27 am

            Without getting into a heated debate, and in response to your first question, you have indeed stated that crows are a problem – on more than one occasion – and that is why I questioned your stance on the subject, especially given the topic of this post. You have made the following statements;

            “Of course crows can have an effect on other birds breeding success”

            “Carrions can be a pest at lambing time as well, they can take eyes out of sheep when down lambing”

            “They certainly will not do any good for the likes of lapwing etc, you only need to watch nesting lapwing to see how harried they are when a crow comes near, then its mate can sneak in and grab an egg”

            “they [Lapwings] have gone from most of Cumbria, supporting crows will not do them any favours”

            I don’t think these examples can simply go down as misinterpretations on my part.

            As for the trapping issue, we will just have to agree to disagree on this. You are clearly in favour of them, whereas I do not agree with their use, so I’m sure we can put that subject to the side.

            We do appear to agree on the problem of habitat loss, and I believe that this is where the focus should have been set many years ago. The Lapwing has been declining for decades now, and crows have been trapped, shot and poisoned for decades, even long before the Lapwing started to decline, so it is quite clear that the control of corvids (and a host of other predators) has not had the desired effect. Crows are clearly not the problem, but the primary problem is habitat, perhaps with climate change as an additional factor. We can go on trapping crows for another thousand years, but unless something is done to re-create the habitat that waders need, they will continue to decline.

            I suppose the RSPB could re-create a Hope Farm-type demonstration in other areas, but such a project will only have localised benefits. The Lapwing, along with other species, needs immediate, major changes to the way habitats are managed, and to the mind-sets of the landowners. In other words, it has to widespread, landscape-scale changes. The repeated failures of the landowners, and their misbeliefs in the predator problem, has to be addressed, as their obsessions with killing clearly does not work.

    • 39 Marco McGinty
      December 19, 2014 at 2:21 am

      Tim, I would guess that most people involved with work in the countryside have witnessed such events, and I must add that there are some farmers out there that don’t give a damn about their animals. A few years ago, during the first of the bad winters we had, I noted a sheep lying in a distant field, and I presumed it was dead. Three days later, as I was passing that area again, when scanning the fields for birdlife, I was sure I saw one of the sheep’s legs move. Believing that the sheep was dead from days ago, I watched it for another two or three minutes, convinced it was dead and I my mind had played tricks on, but then it made another brief movement. I hurried over to see if there was anything that I could do, but it was looking beyond help, with an eye pecked out, and part of its tongue.

      I went out of my way to get to explain the situation to the farmer, meeting his wife and children as she was coming out of the farm on a quad bike. I told her of the problem, explaining which field the poor creature was in, yet her reaction was to drive off in the opposite direction, with her kids playing about on the trailer. She had no food or equipment to suggest she had urgent work to do, so why after three days of this creature lying on the ground in freezing conditions, did she not abandon whatever she was doing and attend to the sheep. I was so angered, that an animal welfare organisation was called that day.

      As for sheep stuck in holes, I haven’t seen any live ones, but I’ve seen many corpses in such situations, again suggesting that some farmers would prefer their animals suffer rather than do anything that could help them – or attempt to prevent the incidents happening in the first place.

      Your assumption that we are favouring some species over others is complete nonsense. However, you have provided that statement as absolute fact, so would you please highlight some examples where commentators of this blog have favoured one wild, native species over another?

      • 40 chasingmytail
        May 6, 2015 at 10:59 pm

        Dear God – you are superior and have to say you have absolutely no idea about farming – just typical! Living on an organic, well well understocked farm, enormous amounts of conservation work done. I have had to endure the loss of half my lambs in the last few weeks – seeing that I only had 20 super healthy (high health status farm) ewes that is quite a loss and financially a complete balls up, not only that but the emotional and another depressing 2 steps forward 10 steps back (feeling suicidal but hey got to keep going as a busy mum) Seeing fresh lambs in complete misery, tongue and eyes picked out and still alive, a healthy ewe stuck in down a bank half eaten alive. Today losing 3 chickens has hit the nail on the head for this high welfare, low import, grass fed, blar blar blar so called happy farming. No other business could put up with this Bull sh@t. Yet the public dont want to see factory farming, dont want nasty farmers keeping animals inside – happy to eat cheap meat though. You cant win can you? Better call the RSPCA quick cos obviously like most farmers we are terrible at doing our job and failing these animals terrible. Get the gun for me old chap!

        • 41 Marco McGinty
          May 7, 2015 at 2:15 pm

          If this is a serious post, then I have a serious point to make here – You appear to be suffering from bipolar disorder, or severe depression. Please consider this, in all sincerity.

  16. 42 sue paduper
    December 22, 2014 at 9:42 am

    Interesting photograph

    Why so many bird in the trap?

    If they are carrion crows why have so many territorial corvids as drcoys?

    Or is the trap not being checked and trapped birds being allowed to build up?

    The general licence is a complete disgrace and SNH are the wrong organisation to be responsible for it

    Who else would permit the use of untested traps .i.e. Clam traps

    Crow traps are being widely abused to trap raptors and everyone knows it coupled with little enforcement is having population effects on raptors.

  17. 43 Pip
    December 23, 2014 at 11:40 pm

    “Myself when young did eagerly frequent,
    Doctor and sage and heard great argument
    About it and about: but evermore came out the
    same door as in I went”
    And that pretty well sums up the posts here – and we’ve had this discussion before and I reiterate my comments of last year – sorry, but the crows killed all the peewit chicks that were hatched in my adjacent field again this year. This is not anecdotal – we’ve watched the poor bloody peewits being harried until they were run ragged and away goes another chick. At present there are at least 60 crows in the field – a murder indeed. And yes, they are clever birds – too clever and too many. That’s an observed fact as far as I’m concerned and that’s good enough for me…………..
    Pip

    • 44 Marco McGinty
      December 23, 2014 at 11:55 pm

      That is an anecdotal account, Pip.

    • 45 nirofo
      December 24, 2014 at 1:58 am

      Nobody’s denying that crows take eggs and chicks, it’s what they do! The point is, if it wasn’t for the fact that Lapwings and many other waders had been decimated to such low levels by years of habitat destruction and land drainage, thereby removing their breeding and feeding sites, then the few eggs and chicks taken by the crows would make little difference to the overall numbers in the UK. The crows haven’t increased in numbers, they too have been decimated by the continual use of traps such as the Larson trap, it’s just that you notice them more because there are so few other birds, crows are generally long lived birds who can survive on a very varied diet, they don’t need eggs and chicks to survive, whereas the waders need specialised habitats and feeding areas, if these disappear then so do the waders.

      By the way, are you sure you saw 60 crows in the field, are you sure they weren’t rooks, I regularly have 50 – 60 rooks in the fields, sometimes more, but rarely more than 3 or 4 crows.

  18. 46 Jeff
    December 24, 2014 at 4:25 pm

    Just wondering if anyone has any insight into the “Understanding predation” project recently launched by the Moorland Forum http://understandingpredation.blogspot.co.uk/2014/12/launch-of-new-understanding-predation.html
    There are a couple of comments and I noticed that “Song Bird Survival have also offered to contribute to the process.”

    • 47 Marco McGinty
      December 24, 2014 at 9:29 pm

      Jeff, I am quite sure that the results will be skewed, and the role predators have in the environment, will be heavily manipulated to suggest that they are a problem, if not the only problem. Many people on here have stated that habitat loss is the main problem facing waders, but the shooting industry cannot accept that, and would prefer to deviously use predators of all shapes and sizes as the problem. The collective failure of the shooting industry to grasp that predation is a necessity of the natural world, is shocking, however it would appear that a minor change in their thinking has occurred. In the fifth paragraph of the item you have linked to, it states that “In developing the proposal, it was accepted that predation is a natural process.” So, despite predation being the norm since creatures first started roaming the earth, only towards the tail-end of 2014 has it finally registered with these people. All those experts, in all those years, yet they didn’t realise that their beloved grouse and pheasants were predators themselves!

      Anyway, Alan Tilmouth has asked some fine questions, so we will wait and see if they can provide any answers.


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