Do crows reduce other songbirds?

A comment I occasionally hear, especially while conducting my research in neighborhoods is, “Ugh, I hate the crows.  All of a sudden we have tons of crows and they’ve scared off all our songbirds!”  This comment always pains me, but I understand that for most people it arises from a genuine concern for songbird abundance and conservation.  First off, as a reminder crows are songbirds themselves; ravens are our biggest songbird.  Semantics aside, I understand that there are many, many bird lovers who just can’t get on the crow bandwagon and when they talk about wanting songbirds at their feeders they mean chickadees, juncos, grosbeaks, etc.  They feel that since the “arrival” of the crows their observations of these other birds have diminished.  So is there anything to this?  Do crows indeed drive down populations of small, “desirable” backyard birds?

I came across this grizzly scene while conducting research in Bellevue.  An adult robin calling frantically while a crow munched on one of its young.  Later that same week I would watch of pair of adult crows chase hopelessly after a cooper's hawk that had taken one of their offspring.

I came across this grizzly scene while conducting research in Bellevue. An adult robin calling frantically while a crow munched on one of its young. Later that same week I would watch of pair of adult crows chase hopelessly after a cooper’s hawk that had taken one of their offspring.

The short answer is: not usually.  Now, let’s be clear, crows will absolutely kill and eat eggs, nestlings and even adult birds if they can get their hands on one.  I once saw a crow take down an adult house sparrow in an attack so quick and dexterous I only realized what had happened after the crow had already started eating its meal.  It’s important to keep in mind, however, that crows are one of many, many animals that are eating the young and adults of other bird species.  Raccoons, squirrels, foxes, hawks, owls, bullfrogs, rats, mice, and of course cats will all gladly eat birds, especially eggs and nestlings.  The vulnerability of young birds is in fact why the breeding strategy of many birds is to have multiple clutches over the course of the breeding season.  Crows themselves are subject to these same predators and very few of their young will make it to adulthood.

Why do we think that crows aren’t responsible for the any observed decrease in feeder birds?  Predator removal studies.  These studies are straightforward and essentially create two populations, a control population that has been unmodified and a second where the predator in question has been actively removed.  Prey abundance or productivity is monitored and compared at the end of the trial.

Recently, Madden et al. published a comprehensive literature review of 42 studies across 9 countries that looked at the impacts of corvid removal on a variety of avian groups including gamebirds, passerines, waders and other ground nesting birds.  They found that in 81% of cases corvid removal made no impact on prey abundance or productivity.  They also found that impacts of corvids on prey species was similar, and no one group was particularly more sensitive than any others.  Of the corvids studied, magpies consistently had the smallest impact on prey productivity, but no difference was found if the study was looking at prey abundance.  So if corvids are such conspicuous avian predators, why doesn’t their removal seem to matter in most cases?

This is explained by idea of compensatory mortality, which is essentially that removing one predator just means that the other predators will account for its absence by eating the prey it otherwise would have.  Kevin McGowan provided a great description for this idea on his site I like to use the analogy of handicapped parking spaces at the mall You drive up to the mall, looking for a parking space in a crowded lot. You can’t find a parking space, but there are four near the entrance that are reserved for handicapped permits only. You complain and think that if only those handicapped restrictions weren’t there, you could park in those spots (common sense). In truth, of course, if those spaces were not reserved they would have been taken long ago, just like all the other spaces in the lot.”  Indeed, Madden et al.  found this to be true.  When they looked at studies that only conducted corvid removal, they found that only 16% of cases saw a difference in prey productivity.  Whereas if all predators were removed the researchers reported that 60% of studies found a significant difference in prey productivity.

What this means for those of us trying to improve the bad reputations of crows and other corvids is that the data is on our side, crows are not usually the problem predators they’re often made out to be (though in a small number of instances they are, and it’s important to acknowledge when that’s the case).  In fact, in 6% of cases the researchers found that corvid presence actually benefited other birds.  So what I suspect is happening when residents ask me why they see fewer birds and if crows are to blame is that crows often follow urban development and it’s possible that what these residents are experiencing is a change in species diversity as habitats are disrupted and modified to make way for new human settlements.  Though it’s also possible they simply don’t know where to look.  It wouldn’t be the first time I’ve listened to folks complain about crows driving away their birds in the presence of yellow-rumped warblers, white crowned sparrows, juncos and chickadees.  Indeed, suburbia is often a great place to enjoy both crows and other smaller songbirds.

John Marzluff's newest book which describes the awesome power of suburbia to become a heaven for a huge diversity of birds.  Illustrations by my friend and colleague, Jack Delapp.

John Marzluff’s newest book which describes the awesome power of suburbia to become a heaven for a huge diversity of birds. Illustrations by my friend and colleague, Jack DeLap.

John Marzluff’s new book Welcome to Subirdia, highlights that vast species diversity that can come with suburban development, showing that these types of habitat modifications aren’t doomed to be low diversity.  With a bit of thought on our part, we can create habitats that attract a variety of birds.  Namely, by limiting lawn space, increasing snags, native plants and bushes and keeping our cats indoors, we can expect to see a great variety of birds visiting our feeders, crows included!

Madden, C.F., Beatriz A., Amar, A. (2015) A review of the impacts of corvids on bird productivity and abundance. Ibis: 157, 1-16.

70 Comments

Filed under Crow behavior, crow conflicts, Crow life history, Crows and humans

70 responses to “Do crows reduce other songbirds?

  1. Nikki

    Thanks for the great article Kaeli, I am a avid crow lover and I too have been faced with the same argument. Now you have given me some good points to argue with.

  2. Scott

    I was wondering what was killing the cedar waxwings by the apple trees on our street, as there were numerous kill-sites ( “puddles” of waxwing feathers) Yesterday I found the answer, as I saw a crow ambush a waxwing and kill it. Now I know.

    • Scott, ceder waxwings are one of my favorite migrants and I would certainly grimace at the loss. But a cool predation event to see nonetheless! Where’s there’s one predator there’s usually more and depending on where you live I’d look for a cooper’s or sharp-shined hawk since they’ll be keeping their eyes on the waxwing flocks as well.

  3. Reblogged this on Kaeli Swift and commented:

    Updated with data from a new review of studies looking at impacts of corvid removal on other birds.

    • Mr g kettleborough

      Recently a group of blackbirds (with young) attacked a crow in my garden
      And he had to be rescued , he is ok now and still comes for tit bits and he can now fly ok

      Geoff kettleborough

  4. Pingback: Clever crows! | Jeff Ollerton's Biodiversity Blog

  5. Not so sure — I was feeding small songbirds — now I have only crows patrolling – not a single smaller songbirds
    I always loved crows and still do but — I monitored the facts on my balconies…

    • While personal observations are a key part of good citizen science it’s always important to remember that the plural of anecdote is not data. Individual results may vary but the vast majority of studies (each which incorporate many more individual data points) suggest that corvids do not reduce populations. But keep watching! Look for other sources of decline too, like neighborhood cats, changes in feeders and development.

  6. We have resident crows and a huge population for sparrows, juncos, finches, hummies and flickers.. oh can’t forget the Robins!! All get along or so it seems.

  7. I don’t have anything against crows. We have noticed a pattern. In the winter, we have all kinds of birds in our yard. There are finches, juncos, chicadees, woodpeckers, bewick’s wrens, red-breasted nuthatches, and titmice, to name a few. Sometime in March, a group of crows starts flying around, cawing, and hanging out in the trees. Until late summer, we won’t see any birds but a few crows, some scrub jays, and an occasional California towhee. Does the threat of crow predation send all other birds to another location? Thanks-Valerie

    • Hi Wendy, what you’re describing sounds like seasonal changes. During the winter the small songbirds you mentioned form mixed-species flocks and move about pretty freely. Starting in spring though, the birds start to defend their territories much more fiercely and it can feel like you’re seeing less. They’re also less attracted to feeders which can mean you’re seeing them in less concentrated abundance. So that’s my guess. To answer your question more directly though, while taking a walk through my neighborhood this winter I counted 10 native bird species in a single yard along with a territorial pair of crows. Crows simply don’t take adult birds down often enough to suffice as a predator that would have that immense of non-consumptive effects (i.e. When predator presence changes the spatial use of prey we call that non-consumptive effects). If you make your yard suitable for song birds to hid in (think native shrubs) then they should easily cohabitate with your crow family. Enjoy the birds!

  8. Andrew Poliakoff

    Hi corvidresearch thank you for creating this great area to discuss crows; I’d love to hear what you have to say about two of my anecdotal experiences and how they fall into what is generally understood about crow behavior.

    I live in Northern Virginia. Both of these incidents were roughly the same and both occurred in residential neighborhoods in late Spring. Last year in May I saw a crow in my neighborhood on top of a chimney that was eating something (I didn’t know what at the time) and being attacked by two Brewer’s blackbirds. The crow had to move quickly and landed on a nearby chimney where I could tell that he/she was eating a baby Brewer’s blackbird. The blackbirds gave up at this point.

    Yesterday I saw roughly the same thing in Old Town Alexandria in a small residential park. This time I saw the crow take the blackbird from the ground and fly with it up to a chimney. Almost 8-10 Brewer’s blackbirds were going absolutely crazy trying to stop the crow for 20 seconds or so and then the gave up; the crow ate the blackbird on the chimney.

    I am writing for two reasons. First, I have Brewer’s blackbirds in my yard here and the babies just emerged a week or so ago and follow the mother (I’m guessing) around in the yard. They are huge for babies, and appear almost bigger than the parents. That’s why I noticed them and what is what is so odd. I understand crows taking fallen babies or defenseless ones from an unattended nest…but…taking a non-injured robust baby off the ground? Is this normal behavior? I ask because the little research I did into this seems to indicate that crows will only eat a bird if it is already physically ‘opened’ because they do not possess the right beak to kill birds. The bird I saw on the ground getting taken did not have that appearance (but I can’t say I was preparing to collect avian data when I turned to see).

    The crows here were decimated (as per my understanding) a decade or so ago by some disease. In the 80’s and 90’s in Northern Virginia there were oooodles of crows (treefull after treefull) and now there are very few. Is it possible that they’re exhibiting strange behavior due to the entire structure of crow communities being lost?

    Thoughts?
    -Thank you, A.P.

    • Hi Andrew, thank you for your kind words. The short answer is that crows are more than capable of killing and opening birds. Most mammals, on the other hand, are a different story because the skin is thicker. Think about it this way; since they are capable of killing each other, smaller birds are no problem. I’ve seen them attack and kill adult songbirds on more than one occasion (both times it was a house sparrow). That being said, they’re not bird eating specialists so while it’s not an unusual behavior it’s also not a common one, if that makes sense. The limitation is their ability to catch birds, not eat them, which is why observations of them eating fledgling are much more common in contrast to adults. On another note, although fledgling are often similar in size to their parents, you might want to google “cowbird fledgling” so see if maybe your big babies are in fact nest parasites. Great observations!

  9. M Hunt

    I appreciate your interest in crows, however, I am currently devastated by the behavior of a family (murder) of crows in my neighborhood. I enjoy hosting sites in my yard for various species of birds, especially the Robin. I have watched a mother Robin spread her wings protectively over her young during a late season snow storm that left her with a half inch of snow over her entire body as she sat through the night keeping the babies alive. This season there is a young pair that worked tirelessly gathering mud from my backyard ( I helped along in this process). They were at the stage where they obviously had chicks and were busy looking for food. The nest was high in a maple tree in my front yard which I was not able to locate visually. Yesterday the attack by the crows began. I knew what they were doing in that tree and watched sadly as one of the crows flew off with a baby clutched in its talons. The mother, father, and I were devastated. I listened to the distress cry from those birds for a half hour and determined that I would do great harm to those crows if they came near another nest. I now understand that crows are protected by law, which is unfortunate, because today they have raided two other Robin nests in close proximity. I have a Robin still nesting near the house and a sparrow in a hanging planter that I am now taken actively protecting from the crows. Make no mistake; I will forcefully clear the area to protect the smaller birds who are being terrorized by this crow family. I can do so without harming the crows, but it will take some vigilance on my part. If they persist I may borrow a cat from friends for a season, and I do hope the cat is successful in returning the favor of nest robbing from the crows. I understand crows can memorize faces and details for several years. I hope they tell each other that they have created an enemy at my address.

    • People have a very difficult time watching baby birds die, understandably. Just the other day I received an email nearly identical to yours, but replace robin babies with crow babies and crow with Cooper’s hawk. The reality is most baby birds will die before the end of the breeding season. I know it’s tempting to think, oh if only I kept x predator away they would live, but this is not the case. They are just eaten by a different predator or fly into a window (something called compensatory mortality). Given that you have three different pairs nesting in your yard I would say your robin population is incredibly robust and I applaud you for creating a space that attracts prey and predator species alike. Given the vitriol you clearly feel for the crows you have attracted I don’t expect you will be moved by this reality and let nature take its course. If you want to manage your yard for individuals that’s your call; both robins and crows are doing very well and I see no harm in your efforts as long as they are within the law. I do urge you however, NOT to use cats. Cats are indiscriminate killers and will harm the biodiversity of your yard, not improve it. Best wishes,

  10. Thank you so much for sharing your wonderful blog! My eight year old son and I just started reading and listening to Gifts of the Crow and love it! Thank you for answering my question about the smaller songbirds. We live in Wallingford (Seattle) and we have a bird feeder in the front yard. We used to have a variety of bird visitors: chickadees, sparrows, robins, pigeons, flickers, stellar jays and even three beautiful waxwings (although the waxwings seemed to be plucking spiders from their webs and not interested in the feeder). We LOVE our crow friends. I was worried because since I’ve been feeding the crows more regularly, we haven’t seen hardly any smaller birds. I am glad it doesn’t have much to do with us feeding the crows and the crows presence. We don’t feed them a lot, just one fried egg yolk and a few unsalted Virginia peanuts. And an occasional bite of leftover salmon from Anthony’s or other seafood restaurant we go to. Do crows taste food like we do? Do they taste salty, sweet, spicy, etc? Thank you again!

  11. Vijay Surya

    Crows must be declared as pests and isolated from liveable environment.

    • Realist

      Amen. I can’t believe the praise for these nasty pests. Will the author defend rats and cockroachs next?

      • Hi Realist! Remember, every comment goes through me for approval before it actually shows up on the blog, so you don’t need to @ me like you did in your second post. I’ll always see it!

        Anyway to get you your question. Sure, in the right contexts! Did you know that are 56 species of rats? Most live in remote areas and some are even endangered like the giant kangaroo rat (go ahead, google it, it’s cute as a button.) Black/ship rats are of course a different story since their introduction into nearly all corners of the globe, and the scientific studies on their consequences, make clear they are among the worst threats to global biodiversity, particularly on islands. Which, PS, there’s really only one invasive species of crow, the house crow, and its global spread is nothing close to the black rat’s. BTW, did you know norway rats (the kind most typically used in labs) “laugh” or at least produce a very specific vocalization when tickled and will seek out future tickles?
        http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0051959
        They will also rescue trapped casemates just for the social points. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3760221/
        I don’t know about you but I think that’s pretty damn interesting!

        Ok on to cockroaches. Rather than being biodiversity threats, the thing cockroaches-well, let’s be specific here, American cockroaches-do is effectively squick people the heck out. Which I get. Turning on the bathroom lights in the middle of the night and having one dart in front of you is bound to give most people a fright. But it’s unfair to generalize all 5,000+ species of roach based on our attitudes of the American cockroach. The truth is, in their native habitats both rats and cockroaches are part of the biodiversity that make their ecological homes run-just like crows.

        As far as me writing my own post? Heck no, that’s not my field of expertise! Speaking of which, thank you for getting me to write this post, I learned a ton more about roaches! Instead, I’ll stick to my corvids and doing all I can to disabuse people of the myths and alternative facts that surround them, hence this very blogpost! For the roaches and rats, I can leave that to the folks that know their stuff. If you want to learn more about rats check out @orderrodentia, @urbanevol or @rattus_mattus. For cockroaches I reccomend @lmcamargos, @lbycter @scibugs. Oh and you seriously have to read this article by @bittelmethis http://www.smithsonianmag.com/science-nature/i-am-officially-in-love-with-cockroaches-180960274/ it’s awesome!!!

  12. Doro

    Hi. I’d be very interested to know if something I just heard is true…that British crows pick out the eyes of other birds. Is this so? Is it true?

    • Hi Doro, I can answer this question but first it would be nice if you could provide a little more context for this hearsay. Where and what exactly was the context in which this was said? That will help make sure I get at the root of what’s being asserted here. Thanks!

      • Doro

        I don’t understand why my replies aren’t showing up now, but I did answer asking if you were being coy? I did provide the context – someone told me that crows were picking out the eyes of other birds, and I asked if it was true that crows do that. Am I not understanding your question?

      • Hi Doro, no I am not being coy. I’m just trying to figure out where this could have come from on behalf of the person who told it to you. For instance did they mean that crows just peck the eyes out and leave the bird blind but alive, akin to how Eleanora’s falcons pull the wings off living birds and store them so they can eat fresh meat later, or did they mean that they just do it for fun akin to dolphins hunting porpoise calves? Or maybe they meant that they’ve seen a crow pick out the eyes of an already dead bird. In any case, there’s no evidence whatsoever of the first two scenarios. The third is entirely possible though. With mammals, the eyes are most typically the first thing they go for because their beaks are not made for breaking the thick skin of something bigger than a rat. This is why they have such a bad reputation among sheep farmers. Eyes are accessible, nutritious soft tissue so once they pluck and consume the meat of a bird kill there’s no reason they wouldn’t fish out the eyes. The other possibility I can think of is that when I’ve seen crows go after small birds their strategy is to kill them by a blow to the head. It’s possible this person mistook a general interest in going after a bird’s head as a specific aim to peck their eyes.
        Cheers,

      • Doro

        Thanks for your response. I’ve never heard of falcons pulling the wings off living birds, and the image of it in my head is horrible. And I’ve never heard of dolphins hunting porpoise calves either – both being indications of my ignorance. I apologise. But you’re answer helps me to understand what you were looking for, and it’s along the same vein as what I was trying to establish in the original conversation about crows.

        Here are a couple of things I was told: In my book all crows are nasty…. They attack small birds nests, and kill baby lambs/ When one of my blond boys was about 2 years old he was out with his Da and he was attacked by one of those, they were going for his eyes. Those critters are no fun/ in Fort McMurray in 1967-9 there was a report of ravens picking out the eyes of young wolves and waiting for them to die.

        I’d never heard of such behaviour and none of the people who made the claims above responded to my request for info that I could check out independently. So when I found your site, I thought you might have the answer. I guess what you’re saying is that the reports are exaggerated – is that fair to say?

      • Well yes and no. They do attack birds nests-they just don’t do it at such a rate in your backyard that we see declines of songbird populations as a result. Everything eats baby birds, it’s sad to see but that’s why they lay so many eggs. They also do peck the eyes (and anus) of young lambs. That’s also a sad sight, but from a foraging perspective it’s a very a good strategy. Nature doesn’t design itself around our sensitivity nor do humans always abide by it. It’s not hard to find evidence of people doing truly heinous things to our food, despite the fact we are capable of holding ourselves accountable for it. The last two though are more exaggerated. Wolf pups are born in dens and do not emerge until they are hold enough to give the crows and ravens chase. I’m inclined to think that one is a exaggeration of the fact they do like to tease wolves by pulling their tails. Finally, in the summer time crows become very defensive around their nests and kids and will dive bomb people who get too close. Although they’ll swoop and occasionally peck the back of the head, they’re not going for the eyes-that’s too risky. A bird in the hand will go for the eyes but this is true of any bird with a long neck and powerful bill. I’ve handled caspian terns before and was surprised when it was over that I had made it with both my eyeballs.

      • Doro

        Thanks for your response. Appreciated. I’m becoming increasingly interested in this topic. As I was trying to find an answer (before I found your site), I came across the following. Would you mind giving me your interpretation on them?
        https://www.realagriculture.com/2015/07/livestock-predation-turns-ravenous/
        http://barrie.ctvnews.ca/ravens-attack-and-kill-livestock-in-grey-bruce-1.2507458
        http://www.owensoundsuntimes.com/2015/07/24/raven-attacks-on-calves-in-chatsworth
        I don’t see any evidence to indicate if these are animals who have been taken from their mothers as often happens in the cattle industry, but I’d be interested to have your take on these. Many thanks in advance.

      • Look legit to me-eyes and anus are good signs of an avian scavenger. I’m not a rancher but from what I can tell domestic cows and ewes just aren’t biologically equipped to chase off looming ravens. Meaning, I don’t think it makes any difference if the young are with mothers or not, their mothers simply don’t do anything about it. I do wonder though, if wild bison and big horn have the same issues, or if because they are co-evolved with this species they are more equipped to watch for and respond to attempted predation events on calves by ravens. I’ll have to ask some of the big game biologists I know. Again though, I’m not a rancher. Perhaps domestic farm animals do try and protect their young from these kinds of attack but just aren’t very successful.

      • Doro

        Hmmm…now I’m getting confused. My understanding of your earlier reply was that reports of them pecking out the eyes of live calves or lambs were exaggerated, allowing for the possibility of “down” calves or lambs being attacked. Your most recent reply seems to suggest that this is to be expected.

        I’ve looked up some more info:

      • I’m not sure what gave you the impression that I thought this (meaning, specifically, pecking lamb’s eyes) was an exaggeration? I said explicitly that they do peck the eyes and anuses of lambs (and I’ll include now, calves). That they peck the eyes of other kinds of more dangerous critters (wolf pups, humans, etc.) is an exaggeration. Does that help? Maybe the confusion is that clarifying if you’re talking about ravens or crows is really important here. Ravens are much more powerful birds than crows so they are actually quiet capable of killing a young mammal under the right circumstance. Crows are not. You started by asking about crows, so most of my answers have been provided with respect to what crows do, not ravens. But it seems maybe now you’re more interested in raven behavior. The video above is of ravens. They could easily pull the eyes and peck to death a young lamb. This would be much more difficult for crows, who would be limited to the eyes and then waiting for it to die and be ripped open by something larger.

      • Doro

        My mistake. I apologise. And yes, you’re right. As far as the crow/raven aspect goes each time I plug in “crow” I get feedback on either both crows and ravens or else just ravens, so I’m unsure if the information is applicable to both or not.

        You may or may not be interested to know that my provincial department of natural resources said that they believe the claims of crows pecking out calves eyes are probably the result of poor animal husbandry. That weak or sickly youngsters may be left unattended, or without a cow to defend them, and since they’re weak, and crows are opportunists, they go after them.

        Again, my apologies for getting your previous answer turned around. I really appreciate the time you’ve taken to help me get this figured out.

      • Hi Doro, yes that’s a common and understandable source of confusion. Not everything will apply to both but that’s just not always made clear, unfortunately. Fascinating that that’s what brings you to ask this question! I’d be very interest in any final report your office publishes on the topic. Animal husbandry issues are a big source of contention here in the states too, particularly as it relates to wolves and cattle/sheep. Range riding is a tough job, but I imagine it could be just as useful for preventing injuries from corvids as it is effective at stopping predation events by wolves.
        Cheers

  13. Jon

    Ridiculous article, masquerade of a scientific paper. The crows are very vicious and work in gangs killing every other small birds, and chasing even bald eagles out of their area (I witnessed such chase in the Vancouver area for many times). The crows population should be kept in check.

  14. Animal murdering a hole

    I was just driving and hit a finch. Accidently of course, I stopped when I had the chance to see if he was still alive. Upon my arrival a crow grabbed it in it’s beak and flew away with it. I was pretty shocked and it lead me to this. Poor little birdie. 😦

  15. Fabulous article and u have really given me ammunition for my argument to try and educate people who hate crows and Maggie’s! Thanks so much, and I feel much better about the new crows and Maggie’s in my garden…!

  16. Patty James

    A cardinal built a nest on the tray of a bird feeder. We had to stop feeding birds because dogs ate overflow even with the catchers on the bottom. What I want to know is how to scare other birds away as to not disturb her nest. It’s right outside our patio door

  17. Brooke

    I live beside an undeveloped piece of property in Seattle. Condos and major roads surround us. There are 2 crows that are comfortable hanging out on my balcony with me & my cat (for about 3yrs now) & the rest of the family hangs out in the trees and makes a ruckus…except durring nesting. Taluk will make an apperance if I call him and Dido will sometimes follow. This morning I saw Taluk chasing a small bird around my condo & into the trees. He was absolutely hunting this bird! I could see and hear him crashing through branches! He finally landed on my railing panting with beak wide open. So, Yes, Crows do hunt. They are not just scavengers or nest robbers. Crows are an ultimate survivor. I am lucky to observe 2 very special crows and their family dynamics.

  18. Kit

    We have an abundance of sparrows, robins and other birds in and around our patio restaurant. Many of them nesting in the cedar hedge surrounding the building. The birdsong is chipper and lively most all day long but a today all of a sudden it turned frantic and angry. I went to see the cause and to my horror a crow had a sparrow down on the ground and was violently pecking it. Several other sparrows and robins were all trying to stop the crow. As I approached the crow took flight with the sparrow clenched in it’s beak. The other sparrows and robins tried to follow the crow but to no avail, it was quickly out of sight with it’s prey. I have never witnessed such a violent attack except one time by a hawk out at a farm property, and so I ended up here looking for an answer. Thank you for all the information and feedback. We don’t usually have crows on this property. They are quite abundant in the general area but seen mostly up on the main road. I hope our property is not a recent discovery for this particular crow as I hope not to witness this again. What are chances this is a one time event here?

    • Hi Kit, unfortunately I can’t give you the odds you might witness something like this again. Probably you won’t but it’s possible you will. As a frame of reference, I spend more time than most people watching crows and I’ve only seen active predation events 3 times.

      On another note I’m curious if you found this episode more, less, or the same level of upsetting as you did with the hawk. I get the feeling that people find predation events between crows and prey more upsetting than raptors and prey, and I’m looking to explore this attitude further. Thanks!

  19. Kit

    Thanks. Yes your right it’s interesting that I was horrified by the crow event and not so much the hawk. I see crows all the time while driving, as they scavenge the roadside and with very impressive timing to hop away and avoid being hit by cars. I’ve always kind of admired crows for what I perceive as cleverness and for just being crows. But because I never saw them attack live prey like that it was the surprise and misconceptions I had that made it more upsetting. I understand better now but just the same I still hope the crow doesn’t return here for a meal!

  20. James

    Crows must die. They also seek garbage and drag it around from yard to yard. I’m tired of seeing nest after nest get robbed. They are a nuisance. Time to get the pellet gun and let crows know who runs this joint.

    • James, you’re angry I hear you. If you just came here to rage comment and leave then adios. But if you’re here out of a passion for wildlife then I have information that can help you respond more constructively. First, garbage in the yard is not a wildlife problem. It’s a person problem. Locking up garbage is possible, and really important for lots of animals. From bears to crows, putting more effort into keeping trash out of reach will reduce conflict. Doing this, of course, takes a momentous attitude shift because we haven’t been socialized to accept this as a normal way of existing with wildlife. But if biodiversity is important to us then that’s an attitude we need to work on. If that’s not the issue, you and your neighbors already do all you can to keep garbage locked up then good for you. Still not a wildlife problem. People litter and wild animals take advantage. Littering is a people problem, period.
      Now for the nests. If you shoot the crows it will make you feel better. Like someone who runs the joint. It will not save the birds (and if someone catches you could land you with hefty fines since it’s illegal). The squirrels, snakes, cats, dogs, raccoons, mice, rats, etc will see to that. If you want to save birds, really make a sizeable dent in the additive number of birds that are killed each year, engage in lights out programs in your city. Start a neighborhood wide effort to make windows more visible with UV stickers. And above all, engage with your neighbors about outdoor cats. That will really make a difference to the smaller birds that share your space.

  21. I just tried to save a little song sparrow from a crow attack. Many smaller birds were also trying to help. I ran over yelling and flapping my arms and it dropped its meal and was harrassed enough by the smaller birds to leave. The poor sparrow had been blinded in one eye and was totally in shock. I am so very sad I didn’t realize what was happening and get there faster. ugh! Next time I see a crow I may throw rocks at it 😦 I am sorry but I hate watching them kill baby bunnies and helpless birds! Get out of my neighborhood and leave us in peace. 😦

    • This has been a tough week for me. From crows to coyotes to bears, it’s been conversation after conversation where the sentiment is: if an animal kills another animal it has no place sharing our spaces and we must eliminate it. These attitudes are devastating to ecosystems and biodiversity. Wolves, for example, are “heartless, evil animals” because they hunt in packs. Really, this idea that wolves are cruel because they are pack hunters is a big reason they continue to be so persecuted (and in some places executed). It gets emotional for me too eventually. This idea that people just want bunnies (which, ironically, also eat baby birds) and small birds. Just prey species and no ecological complexity. It just makes me sad to see this attitude so pervasively this week. It makes me wonder if keeping sharks, bears, cougars leopards, venomous snakes, on this planet is a fight we may see meet a tragic end. Anyway, switching gears to your specific experience, from the sparrow’s perspective I truly urge you not to intervene. The chances you could save it are slim and if you simply put a stop to things after it’s been mortally wounded you’re just prolonging its passing and making that interim time tremendously more stressful (I promise you the sparrow will not sense your good intentions and will instead react with an intense freeze/stress response to your handling.) It’s hard to witness death, I know, but I promise it’s better for the bird to just let it happen. Then, use all that energy you have to help birds on a larger scale. Things like speaking to neighbors about outdoor cats, bird proofing your windows, etc. Its great you have so much passion, use it to address those things that we have the power to change, like how our actions as humans affect wild birds and other wildlife.
      Cheers,

      • I know it is really upsetting to see helpless animals being killed and eaten by others AND if you really want to help birds on a larger scale, there’s so much we can do! The Audubon Society lists ten things we can do for birds here: http://www.audubon.org/magazine/march-april-2013/10-things-you-can-do-birds
        We can work together to try to save and protect their natural habitats by eating lower on the food chain, using less plastic and keeping plastics and other pollutants out of the ocean, forgoing pesticides and buying organic products if possible, reducing our carbon footprints and keeping cats indoors. We built three outdoor cat patios (catios) and our cats love them.

      • Doro

        Hi. If it’s any consolation, I really admired your controlled response yesterday to the pellet gun threat. You do a great job in educating people (myself included) on the pros and cons of crows and nature.

        Baby birds and bunnies have two enemies that are MUCH worse than crows will ever be. While the crows kill those creatures to survive or feed their young, cats and man do not. Domesticated cats kill tens of thousands of birds and bunnies every year. Man – humans – have to be the worst species on the planet. There is no other species that does the ghastly things to animals or their homes than humans. Before we pass judgement on one creature for trying to survive another day, we need to take a close look at our own behaviour.

        Who tosses plastic wrappers into waterways, plastic bags into oceans where creatures become trapped and drown? Humans. Who bulldozes the homes and young of innocent creatures (birds, rabbits, skunks, snakes, etc) to build housing that we buy and live in? Humans. Who uses pesticides and other poisons that both kill and contaminate the food supply of other creatures in the name of agriculture or gardening? Humans. Who lets their cat out to roam free and doesn’t want to believe that it kills birds, mice, rabbits, snakes and other species when it’s out of sight? Humans. The crows have a long way to go to conduct themselves as heartlessly and with such vulgarity as we do. No, it’s not nice to see a kill, but the victim quickly goes into shock and is no longer aware of its fate. Nature is merciful. Interfering means that a bird who would not have been supper, now will have to become supper to make up for the bird that was dropped, and died anyway.

        Kaeli: Please don’t let yourself be discouraged. We need your input, and the crows need it even more. You are doing wonderful work with this educational site. I know you’ve helped many crows through your efforts. Don’t give up.

      • Thank you, Doro, I really appreciate your kind words.

      • You are perfectly correct! I wish I could edit my stupid comment and I apologize for being an idiot. I love all living things and understand the power of balance in the ecosystem. It does seems that some animals just have the worst of it. It was awful to see and I do wish that I had left it alone altogether as the bird died uselessly. Really stupid of me 😦

      • Wow, I was not really expecting that and I really appreciate that you wrote back (I think it’s the first time anyone ever has). I get it, it’s hard not to feel a little shaken up after witnessing something like that and it would be easy to feel like an injustice has occurred that needs to be remedied. Or at least vented about! I always tell people; feel those sad feelings. But then remember on the flip side is another baby bird that did eat and survive because of that event (the crow, or hawk or falcon, etc. baby). I’m at least glad you care for the birds at all, philamb since that’s the starting place we need more people to be!

      • kris0723

        I thought your readers might be interested in this. It is from Lyanda Lynn Haupt’s book Crow Planet, page 196. “Crows are normally believed to be notorious nest robbers, consuming both the eggs and nestlings of smaller songbirds, but John Marzluff’s research suggests the need for a nuanced reading of this prevalent crow mythology. In extensive studies involving artificial ground nests, shrub nests and canopy nests, Marzluff found no positive relationship between crow abundance and the rate of predation. Crows do prey on nests, he concluded, but they are just one of the nearly twenty potential nest predators, including large and small mammals, owls and hawks”.

  22. In a tree-lined residential street of Berlin, Germany, I have built up a close acquaintance with several crow pairs (corvus cornix, hooded crows) over about 5 years. Their territories are stable, and most of them appeared well established and no longer young birds when I first met them. One pair only were obviously in their first mating year, another seemed already comparatively old, and now no longer appear to reproduce, however still hold their territory, assisted by an adult daughter for the last several years.
    My closest acquaintances come to my fourth-floor window sill every day for food (meat, nuts, occasional fruit, cheese, egg) and water, and (while never abandoning due caution) are happy to eat out of my hand. Others fly down out of the trees to meet me on the street. Some residents complain, quoting the usual uninformed misperceptions. I am convinced that regular feeding (in small amounts) will never lead to these birds loosing their hunting/foraging skills. Have observed the swift ‘murder’ of a young flying songbird and the efficient dispatching of a large mouse. However the quarter is still well populated with all the common smaller species found in the suburbs here – including nuthatch, sparrow, robin, tree-creeper, blackbirds, black-caps, jays, magpies, striped woodpeckers, a nightingale or two etc.
    The crows generally show extreme caution in their daily living, keeping a low profile as far as possible, but are still strongly disliked by many humans, which they appear to realise. On the other hand, it is possible to make eye contact and establish an initial ‘social connection’ with them very quickly, with the help of food of course. Building trust and getting closer can take much longer, but is for me immensely rewarding, as one comes to observe individual behaviours and characters, the influence of the environment and the season on these, and eventually establish the nearest thing to a ‘friendship’ that one can have with a ‘wild’ creature. I attribute this to their intelligence and adaptivity, and probably also to a corvid culture established over thousands of years, whereby observing and following other animals, including us, has proved profitable. As it was in their interest to understand and predict our behaviour, they have become adept at this, and have no difficulty communicating with us if the occasion demands.
    I have no idea why it is considered amazing that all crows can recognize individual humans. Slightly embarrassing however that most humans can’t recognize individual crows …
    Thanks for your blog, always enjoy reading the posts!

  23. Realist

    @corvidresearch, will your next post be in praise of rats and cockroaches?

    • Doro

      Well MY next post is to acknowledge the intelligence and adaptability of rats and cockroaches. I will further acknowledge that neither rats nor cockroaches do the deliberate harm to other species, or the planet, that humans do. Look at thyself first before ye find fault with others.

  24. Raif

    *****I make my point toward the end, but this is my background on crows.
    Simply, I appreciated crows when they were more rare… even their fairly squabbly sounds. I appreciated their stalwart flapping, “honestly” working their way across the sky. I still do love them in the desert, probably ravens… solo, in pairs, or at times a bunch of them playing in the winds.
    I just moved back home after 8 years of more city life. There are now groups of 20+ crow in the mornings and evenings. During the day they hang around haggling over whatever, solo or in groups of 3-5.
    My appreciation for them is past tense. They take over the sound in the neighborhood. Their volume and franticness demand attention. My thoughts have been more than aesthetic.
    From your article, I admit I must check my thoughts about how crow affect other birds locally. Until your article, it was easy to think that a large crow group would eat a large amount of local birds. We’ll see. I realize I must pay attention objectively, in order to get a good, though still very subjective sense of the birdlife here compared to how it was pre-crow. I’m going to check with local bird-watchers to see what they’ve observed re songbird population here.
    1. ***** However much there are other active predators of local birds, this particular predator population has boomed. If there was a balance before, it is out of balance now. It has to be, unless there are many fewer cats, rodents, hawks, etc. Could it not easily be that as the greater San Diego region’s population has boomed and the added crow are having to spread out? “Go West, young crow, go West!” Call it too much of a good thing or a bad thing, it’s too much. Or better, don’t call it good or bad, but… just so. However it’s called, this situation is not neutral.
    2. **** What is your opinion of this product:? Just before finding your article and the great conversations in this thread, I found an ad for a CD that offers a sound that drives crow from an area. I have access to speakers that can emanate sound in a very tightly focused area, kind of like a sound hose. That way it won’t disturb neighbors, much, and I can just hassle them until they move on to someone else’s neighborhood and, probably, birds. I could also put on my camo, and plug a few with a shiny pellet gun, but that has its risks.
    3. **** I’ve very much appreciated your even hand with this thread… very much. I wonder, what could you and science offer people like us who don’t want crow in our neighborhoods and also don’t want to kill them?

    Again, thank you for launching this valuable conversation and thanks to people who post here.

    • Hi Raif, I’m glad you’ve found this article and the conversations happening here helpful. The short version of your story is that crows come with development and certain other kinds of birds will leave with it. In that case it can be difficult to parse causation with correlation, which is why studies and reviews like these are so vital to really understanding what’s going on. As far as your CD, I did a quick google search and everything that popped up looked pretty bogus to me. Claims like “it works on all species of corvid” and “drives crows away but not songbirds” tell me there’s not a very good handle on the basic biology of these animals by the people making them. Plus, if it was that effective that’s what cities and airports would use…but they don’t. The best deterrents are either falconry abatement methods, or a multifaceted approach using a combination of things, including noise. As for my other advice, I assume if you’ve read through the thread you’re already very familiar. The more shrubby and “wild” you can make your property the more attractive you make it to all kinds of wildlife. Crow like grass, garbage and a few trees. Unless we can begin to adopt a cultural norm moving away from this classic American aesthetic, we will need accept the company of our like-minded avian neighbors.
      Cheers,

      • Raif

        Thanks for the continued conversation. Yes, as in so many occurrences in our lives… causation vs correlation? I could possibly do what it takes to like them. I was really looking forward to peanut-training Scrub Jays as I did so thoroughly at my previous house. Maybe I fiddle with the crows…?
        Yes, the CD-sounds seemed a little sketchy. I might just try it and see if there’s any reaction at all. Who knows? If I do, I’ll report back.
        This shift is part of a longer arc of life, death, and aesthetics – as you say.
        -Off to go check out some Heckle & Jeckle cartoons to pick up some pointers… Thanks again.

      • Hi Raif one last suggestion…and I promise this isn’t a shameless plug…but you should consider following the blog. Given your outlook I think you would find the articles and ensuing comments worth your time. Even if you just pursued the other existing articles’ comment sections. There are other people who arrived here after many years of hating crows. You may find their stories relatable or interesting.
        Cheers,
        Kaeli

  25. Rebecca Lynne

    How could anyone enjoy a crow with that obnoxious “Caw! Caw!”

    We have lived in our home on a beautiful river in N Florida for 22 yrs. We have enjoyed many different birds, but
    suddenly a few weeks ago the crows moved in
    and every other bird seems to have left. Totally
    quiet, no bird song to wake up to in the morning. During the day, I enjoyed listening to the songbirds, since the crows moved in, total silence, unless they start up their cawing.

    We have owls, hawks, eagles, osprey, many water birds, woodpeckers, cardinals, robins, and many other birds. I will also add we have plenty of squirrels,& raccoons, We even have snakes. We have had our birds throughout all this. Until the evil crows showed up.

    I would like to see them try to get an osprey hatchling from it’s nest. The ospreys are aggressive and have razor sharp talons.
    I believe they would rip those crows to pieces

    Is it possible the birds are still here and are just being quiet?
    Is it possible the crows are passing through?
    Why is it against the law to kill a crow? Are they endangered? Why do some people associate crows with evil and death?

    Is

    • Hi again, Rebecca. I responded to your other comment as well but let me address a few things in this one. First, let’s start by checking our language. If you’re coming at this from a viewpoint that crows are “evil” we’re not going to get anywhere (which, maybe you have no desire to anyway, but you asked questions so I’ll provide answers). I don’t say that because I need you to like crows or be open to liking them. I say that because your word choice implies that you’ve already attributed an moral lens to what you’re observing. Crows aren’t evil or malicious because those things require morality. A crow isn’t anymore evil for killing a smaller bird that a wolf is when it kills your dog, or a snake for biting you, or flicker for drilling a hole in your siding. They’re all just exercising normal parts of their behavior in ways that happen to really hurt/irritate/infuriate us. But they do them without malice and that’s really important to recognize because it removes the adversarial feeling we might otherwise have and makes it easier to recognize the biology driving the behavior.

      Ok that aside let’s look at your situation. That WOULD be really frustrating. But let’s think about this. Crows are opportunistic hunters. Most of what they eat is insects and garbage. From your description your smaller birds have survived (as they should) living among both specialized predators like raptors and snakes and other opportunistic predators like squirrels and raccoons but have somehow not survived an animal that hunts for less than 2% of its diet. Does that make sense? Especially since some of those predators you listed also hunt crows? How could crows be killing more birds than the accipiters (bird eating hawks) you’ve already shared your space with? Biologically that seems really strange, especially given the concept of compensatory mortality and the fact that some of the birds you listed as now missing (like adult waterbirds) are not ones that would be prey to crows.

      Now, what may be happening is some other change to your system that is both attracting crows and driving out other species. Development is often the culprit here. You may also be observing a normal seasonal change that, complimented with more crows than normal, is making you detect absences that you normally don’t.

      As for your other questions. It’s illegal to kill crows because they are part of the migratory bird treaty act like all native songbirds. Our continental crows are not endangered but, fortunately, that’s not a requirement for being on that list. Otherwise there would be nothing to stop people from killing all sorts of bird willy nilly. There are, however, some very endangered species of crow. The Hawaiian crow is one of the most endangered animals on the planet with only about 100 individuals left. Despite their cultural significance to the Hawaiian people, their role in forest regeneration, and their unique biology (they make tools!) they are nearly extinct in part because so many hunters shot them so they couldn’t alarm call and scare off the feral pigs they were hunting. Can you at least imagine given that story that it’s a slippery slope when people start deciding what animals get to live or die based on our own needs and perspectives? The ecological role of the Hawaiian crow and the (I assume) fish crows you are dealing with are not the same, so I’m not trying to create an equivalency here, I’m just hoping you’ll consider how things like this get really dicey.

      As for your last question. That’s a really fascinating topic that is hard to summarize but probably the easiest way is: crows would eat dead/dying people after battle and during mass disease related die offs (i.e the plague.) In western cultures we don’t like seeing our dead consumed by other animals, so there’s a really strong aversion to animals that engage in this behavior. I’m glad you recognized that that’s not a ubiquitous attitude though. In some cultures it’s actually part of the funeral rite to have bodies (or representations of bodies/souls) consumed by crows and other animals. Humans are a fickle species.

      Let me know if you have other questions.

  26. Rebecca Lynne

    I say “where there is smoke there is fire.”
    When people tell you consistently the crows
    drive away their songbirds, I believe the crows
    do. You can make your data prove anything
    you want. I know, I haven’t heard the first
    songbird since the crows, came to our street.

    I don’t know if the crows killed the songbirds,
    or they ran away. Calling crows a songbird is
    a stretch.

    I can’t imagine anyone being so enamored over crows. We we blessed to watch a pair of
    Osprey nest and raise their little one 2 years in
    a row, when the house next door was vacant
    and the Osprey built their nest on the end of the vacant house pier. I could see the babies
    being fed with my binoculars. Then the mother
    flies to get a piece of Spanish Moss, evidently
    there was a spot that needed more padding.
    Then she spread her large wing span over them. I guess it was nap time. We watched them learn to fly. We fell in love with them and
    even gave them names.

    • Saying “you can make your data prove anything you want” is a misunderstanding of the way the scientific process works. That kind of mistrust is why so many remain unconvinced that climate change is real despite the overwhelming evidence. If you understand climate change but see your logic here as being different from climate deniers I can tell you it’s not. You’re rejecting evidence because it doesn’t suit your personal experience.

      As far as calling them songbirds-that designation comes from their physiology not their size, diet, or vocal repertoire. There’s no stretch there, just evolution.

      If you read through the comments you may begin to understand why people adore them. Or not, which is ok too. You don’t need to like crows. But mistrusting science IS an issue that deeply impacts everyone and is something you should open yourself to remedying.

      • Rebecca Lynne

        I would never want to see any animal become extinct, and every effort should be made to protect an endangered species. That is heartbreaking to me and it sounds like people are breaking the law. And perhaps not enough effort is being made to enforce the law in Hawaii?

        Are you aware there is a season for hunting crows in Florida?
        Since they are migratory it is regulated by the Federal govt. and not by Florida.
        (Florida Sportsman Feb 2016)

        I don’t know if there is a crow season in other states.

        I absolutely do believe in Science. My daughter in law is a Neuro Scientist with a PhD from an Ivy League School. I also worked in the medical field for 25 years holding a professional license. This is a familiar phrase: “MORE STUDIES ARE NEEDED”

        About your data on crows, I don’t know if I trust the numbers. It is not arrived in a stable, controlled setting like a lab.
        You are not an impartial observer.

        I believe in Science, yet I am not completely gullible. I have seen studies abandoned because there was a bias that was not anticipated at the beginning.
        And horrible things have been done in the name of Science, within the last 100 years

        Thanks for answering my questions. It had occurred to me that perhaps this was seasonal and I had not noticed it before. The Osprey may have already
        migrated. I really don’t remember a
        time of no bird song.

        You are very patient with people who comment who don’t agree with you.

        I read an autobiography several years ago, a young woman wrote about her childhood, her parent were organic farmers in Maine. Her sister died in a drowning accident in a pond on the farm.
        She noted that one of the farm workers had said there had been a crow about the farm that summer before the accident. Would that have been unusual
        for a crow to be alone without other crows?
        I suppose some people still think
        them a bad omen. I don’t know why she
        decided to put that comment in her book.

      • Hi Rebecca, yes there are seasons in every state though some states have a lot more participation than others.

        Your criticism of wildlife science is not an unusual one. Folks in field like physics, molecular biology etc, sometimes refer to things like animal behavior or wildlife science as “soft sciences” (though that attitude has changed a lot) for the very reason you state: it’s not in a lab and we can’t control everything. But of course if that was our criteria we could never learn much about wild animals in the wild!

        People can never be completely impartial observers (though I want to be clear: the data I reported in this article are from many different studies none of which were conducted by me) but that is why large sample sizes, as carefully controlled field experiments as possible, and the peer review process are so important. They act as the checks on the issues you describe.
        It’s always better to have more data but, as I said, the finding that crows largely do not affect local songbird populations is based on many different studies conducted by many different scientists.

        As for your lone crow story. Generally they are in a flock or with their mate but it wouldn’t be that unusual to see a crow by itself. But because crows have been part of human culture since basically forever, our urge to read symbolism in their presence/activity is strong and runs deep. Goes to show what powerful animals they are in our lives right? You wouldn’t have seen the same inclusion if they had seen a robin or a blue jay instead!

  27. whitecollarredneck

    This site has softened my perception of the crow as nuisance. However, you stating that it is illegal to hunt crows is simply inaccurate.
    They have a hunting season in NY, Sept. 1 – Mar. 31

  28. Hi Whitecollarredneck, can you tell me where you saw the claim you are describing? I am well aware that there are legal hunting seasons and in fact have a post dedicated to describing the legal (and illegal) forms of “take” with respect to crows. I even acknowledge that “yes there are seasons in every state though some states have a lot more participation than others” in the very thread you are responding to. Thanks!

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