Suppose you're interested in the anatomy and biology of ground hornbills. Now suppose that you get the chance to make physical contact with one of these awesome birds. Here, at last, is the opportunity to get bitten!! Surely you've always wanted to know what it feels like when a ground hornbill bites you. No? Ok, maybe it's just me. Anyway, the opportunity to get bitten by a ground hornbill presented itself to me a few weeks ago, so who was I to miss out?
As I can now confirm from personal experience, it turns out that ground hornbills don't bite hard enough to hurt. My impression is that the bird just wasn't able to exert enough force to, say, crush a large beetle or snail shell, let alone break the bones of a vertebrate prey animal. But, then, that isn't what these birds do anyway: they grab things with their bill tips, squeeze them, and shake them and/or beat them against objects or surfaces before they go limp enough to be thrown to the throat and swallowed (Burton 1984, Baussart & Bels 2010).
I find this interesting because a criticism that's been levelled (informally) at the 'terrestrial stalker' models as goes azhdarchid pterosaurs (Witton & Naish 2008) is that they lack evidence for a strong bite (and that strong bite, so it's been inferred, is required, so it's been suggested, for the terrestrial stalking hypothesis to work). Well, so far as I can tell, ground hornbills - the best extant analogues for azhdarchids, according to Witton & Naish (2008) - don't really have a strong bite either. Incidentally, one more thought on that Witton & Naish (2008) while I'm here. The metrics associated with the paper show that it's been viewed more than 16600 times, and the pdf itself has been downloaded more than 1700 times [graph below, generated by PLoS ONE metrics, shows steady and apparently continuous increase in viewings of our article. Interesting]. The following occurred to me recently: does this mean that it can perhaps be regarded as the most-read pterosaur article of all time? I don't know, but it's certainly possible. Anyway...
This is, of course, all just a bit of fun (and it all started out as an excuse to use the photos you see here): it doesn't really tell us anything about the bite strength of ground hornbills, or about the strengths and limitations of hornbill jaws or skulls in general. After all, we don't know that the bird was biting especially hard (it might, for all we know, have been being gentle with me), and we don't know how much pressure needs to be exerted on my fingers before that amount of pressure is actually "a lot" (whatever that is). And maybe human fingers (or my fingers in particular) are poor at gauging pressure - I certainly seem to be poor at gauging everything else. So, maybe the bite of that hornbill was, actually, really strong.
Want to compare my idiosyncratic and potentially grossly inaccurate whimsical musings with some hard science? Well, tough. So far as I can tell, there's no empirical published work of any sort on hornbill bite strength. Indeed, there's little on birds in general: a couple of studies have been published on finches (van der Meij 2004, van der Meij & Bout 2004, 2006) and Degrange et al. (2010) recently reported data from seriemas and eagles, and published an estimate for the large phorusrhacid Andalgalornis [one of their figures is shown here: see their paper for the full story]. Robust-billed finches like the Hawfinch Coccothraustes coccothraustes bite at somewhere between 310 and 700 N (this was previously discussed in the article Coccothraustes: most bizarre of finches), seriemas and eagles bite at about 50 N, and the suggested bite force for Andalgalornis is 133 N. This is low for a predator of its size (c. 40 kg): mammals with that sort of bite force include otters, jaguarundis and grey foxes. But, then, I wouldn't much like to be bitten hard by an otter or jaguarundi. British wildlife TV presenter Terry Nutkins lost two of his fingers to a pet otter he once kept.
I've now been bitten (sometimes by design, sometimes not) by a reasonable variety of birds, the majority of which are of course too small and too weak-jawed to hurt the human they're biting. Owl bites don't hurt (as discussed recently, their power is in their feet), but I'm not sure about falcons, hawks or eagles (please do say if you have direct experience). But even really big birds - waterfowl and ratites, for example - have weak bites for their size: ratites in particular have flimsy skulls and small jaw muscles, and power-biting just isn't something that you need to do when you make a living from picking at shoots and seeds and grabbing insects. Swans and geese (I've now been bitten by many) can't really hurt by biting alone, but some of them have a nasty habit of 'chattering' their jaws on your fingers. I don't know why. A Chinese swan-goose Anser cygnoides did this to me and broke through the skin, causing tiny, pin-prick like marks in my skin thanks to the serrated edges on its rhamphothecae [the adjacent photos show Mute swan Cygnus olor, Greater rhea Rhea americana, Greylag Anser anser, and my hand].
It's a different ballgame when we start thinking about parrots, and let's just say that I don't much want to get bitten by one. A cockatoo did once bite right through my jacket purely for its own entertainment, and a Kea Nestor notabilis bit through my camera strap because I was stupid enough to let it. Then again, having a scar caused by parrot bite might be pretty cool. A lot of people who do hands-on work with animals have neat wounds: I always like that scene in Jaws where Hooper and Quint are comparing their healed shark injuries. Well, that's just like real life.
For previous articles on bird feeding behaviour, biting and such, see...
- Coccothraustes: most bizarre of finches
- Terrestrial stalking azhdarchids, the paper
- At the 56th SVPCA - hello Dublin! (discusses feeding behaviour in waterbirds)
- B. rex!
- When tapirs don't attack, and when Meller's duck does
- Condors and vultures: their postures, their 'bald heads' and their sheer ecological importance
Refs - -
Baussart, S. & Bels, V. 2010. Tropical hornbills (Aceros cassidix, Aceros undulatus, and Buceros hydrocorax) use ballistic transport to feed with their large beaks. Journal of Experimental Zoology Part A: Ecological Genetics and Physiology 313A, 72-83.
Burton, P. J. K. 1984. Anatomy and evolution of the feeding apparatus in the avian orders Coraciiformes and Piciformes. Bulletin of the British Museum of Natural History (Zoology) 47, 331-443.
Degrange, F. J., Tambussi, C. P., Moreno, K., Witmer, L. M. & Wroe, S. 2010. Mechanical analysis of feeding behavior in the extinct "terror bird" Andalgalornis steulleti (Gruiformes: Phorusrhacidae). PLoS ONE 5 (8): e11856. doi:10.1371/journal.pone.0011856
van der Meij, M. A. 2004. A tough nut to crack: adaptations to seed cracking in finches. Unpublished thesis, Leiden University.
van der Meij, M., & Bout, R. G. (2004). Scaling of jaw muscle size and maximal bite force in finches Journal of Experimental Biology, 207 (16), 2745-2753 DOI: 10.1242/jeb.01091
- . & Bout, R. G. 2006. Seed husking time and maximal bite forces in finches. The Journal of Experimental Biology 209, 3329-3335.
Witton, M. P. & Naish, D. 2008. A reappraisal of azhdarchid pterosaur functional morphology and paleoecology. PLoS ONE 3 (5): e2271. doi:10.1371/journal.pone.0002271
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Can't speak for hawks and such, but black vultures can (and will) break the skin. Although that may have been a closed beak strike as opposed to a "bite" (he was above me while I was cleaning and got me on the head).
Also spoke with a zoo educator earlier this year who had a king vulture bite a tiny piece out of her leg, toss it up in the air, and swallow it. Ewwwww.....
I have often been bitten by large toucans. Same deal---they have no bite strength to speak of. Grosbeaks and cardinals hurt.
Interesting that you say owl bites don't hurt: I once took a pearl-spotted owlet out of a net and it lay flat on its back in my hand with its eyes slitted and when my other hand passed over it its beak stayed shut but its feet kept clenching and opening and readying itself to grab. With its feet restrained it was very easy to ring and it never attempted to bite. I didn't want to test the strength of its claws on my tender skin
I should add that there is some physics involved--- it would be very very difficult for any long-billed bird to have a strong bite (at the tip of its beak). Short stocky bills like those on parrots and grosbeaks are the bills to fear.
I have read (a book by Alexander McCall Smith, I forget which one) that ground hornbills are regarded with superstitious fear in parts of Africa, perhaps because, as you have suggested, Darren, they are creepily similar to people. I hope, before you held your finger out, that you had observed the bird and had already concluded (perhaps unconsciously)that it was not going to bite very hard. Holding a finger out to see how hard an animal bites seems to me to be a quintessential "stupid human trick," the sort of thing that seems quite natural at the time, but that one might feel silly about afterwards, depending on the result.
Sadly my coati injuries have all healed and the tiger never really broke the skin, so I'm limited to far more boring scars.
I would say most birds don't bite hard because that is not what their bills and skulls are built for. Hooked bills are useful for tearing, but that's it. Even chickens can break through skin if they hit you hard enough, but that doesn't equal a bite. Storks and herons can hurt considerably but only because they use their bills as spears. And I suppose a woodpecker might do quite a bit of damage but again, not really a bite. Parrots are a different matter. I have seen a Hyacinth Macaw bite right through a man's thumb. The man said several unprintable things and ran away, so I picked the macaw up, wiped its bill and let it hide its head inside my jacket until it had calmed down (at Rotterdam Zoo, when they still could trust the visitors not to walk away with the parrots).
I once got a warning nip from a mini-macaw. It was an escaped pet, and it left a nice notch in my finger while I checked its band. Interestingly, it didn't quite leave a bruise, so I think the nip was a warning to play nice with its feet. Nice bit of control too.
As for the hornbills and similar birds an interesting question isn't bite strength, it's how they generate the whiplash to beat their prey to death sideways. that takes some muscles somewhere, along with decent connective tissue in their necks. How does it show up in their necks?
The reason I bring that up is that the neck architecture for azhdarchids has to be important in how they used those bills they had. If they all had stiff, comparatively weak necks, it would be harder to suggest that they killed like hornbills. Conversely, if they demonstrably had necks that could generate sufficient torque, the model is strengthened.
Unless, that is, you're suggesting that the azhdarchids simply picked their prey up and tossed it up, to drop on a rock...
I have been bitten by quite a lot of North American songbirds plus a few owls and parrots. In order of increasing bite pain: Purple Martin, warblers (only hurt when they grab a hangnail or cuticle), thrushes, woodpeckers, Steller's Jay, small sparrows and finches, chickadees (they tend to hammer and grab at wounds), Northern Saw-whet Owl, Barred Owl, larger sparrows and finches, Spotted Towhee, Northern Cardinal (hurts like a @!#$%), small parrots and cockatiels (left me bleeding and teary-eyed). The worst part about Northern Cardinals is that they have two equally awful techniques: pinching with the full force of the bill tip like a pair of sharp pliers and sawing with the razor-edge of the bill as if they're trying to split open a seed. I have to say though that the worst pain I ever experienced banding (ringing) birds was when a Northern Saw-whet Owl drove its talon UNDER my thumbnail. OUCH.
Just adding to the database, I can attest that Cassin's finch bites are very painful, and black-headed grosbeaks even more so. Scrub jay bites are also painful, but not as much as the previous ones. Hairy woodpeckers tend to stab, which makes it really hard to get their tongues free of the mist net (they tend to get stuck by that terminal barb).
If we are comparing bites - well, weavers (expecially thick-billed weavers)are bastards - they pinch and twist and they don't cut the skin but you hand feels like someone has been going at it with pliers after you have taken 50 out of a net. Shrikes, which I expected to be bad, really were not that big of a deal though - fiscal shrikes can bite (and like Corvid says, if they get under a nail...), but big shrikes like white crowned shrikes are gentle and docile. Kingfishers like to hammer your knuckles and that can get a bit wearisome, but still not as bad as weavers.
I've been bitten while banding Laysan albatross & Wedge-tailed shearwaters. The problem with seabirds- though this is based on just those two species- seems to be more the slashing than the bite pressure. The sides of their bills are really sharp.
The beak as spear is always fearsome - some large waterbird would have taken my eye out at the London Zoo when I was a kid if I didn't move my head quick enough. Can't remember if it was a stork or heron. Australian magpies are no fun in nesting season for similar reasons, although it's more of a divebomb buffet than a deliberate spearing.
In Australia we were always told to hold the hand out flat when feeding emus so I never got a chance to test their bite strength. [Conversely I can say Tilqua skink bites hurt like buggery and they don't let go]
There's an account in one of Gerald Durrell's Corfu trilogy where he got bitten by a large gull and likened it to being hit with an ice pick.
I can test out your thesis with the local range of Hornbills at the Bangkok zoo, but I'm not sure my health insurance covers bird attacks! :-)
Just adding to the list: bites from large falcons are quite damaging, and bites from red-tailed hawks do moderate damage (personal example: roughly 4 hour paralysis of the median nerve following a bite to the antebrachium). Neither comes anywhere close to the talon pressure, of course.
Parrots of all shapes and sizes deliver a very nasty bite. Budgerigars, lovebirds or *Forpus* might be small, but they have a bite fitting their granivorous diet. Keep in mind that for most parrots, the beak is more than just a huskbreaker but also used as a weapon, to tear, to pull, to crush and as a general tool o' destruction. (Making their ability to perform delicate tasks such as gentle allopreening and carefully feeding tiny hatchlings all the more impressive.)
Having been bitten a few times by Amazon parrots myself I can also mention that they don't just crush or tear when they bite, but also painfully twist a tiny area of one's skin. I've once been nearly bitten by a blue and yellow macaw, but thankfully got away with the upper bill just hitting my fingertip. I can only imagine the damage a hyacinth macaw or palm cockatoo could do.
The links to the skulls below should give some indication of the likely huge strength difference between *Amazona dufresniana* and *Anodorhynchus hyacinthinus*:
Compare both to the skull of everyone's favorite herbivorous parrot, the kakapo. The difference is striking.
We have a lot of bald eagles in our town--seriously, they roost on every telephone pole and crap on the cars--so I've had quite a few eagle encounters, organized and impromptu. Something an eagle handler told me once stuck in my mind: Watch the claws, not the beak. The claws are powerful and nearly inextricable; the beak is an afterthought, and nobody he knows ever got an eagle bite. The bird is only slightly less likely, he said, to try to punch you with its wings.
I've only been bitten by waterfowl--mallards and Canadian geese. Neither of them bite very hard at all, but the duck did try to hang on for a little while.
"But, then, that isn't what these birds do anyway: they grab things with their bill tips, squeeze them, and shake them and/or beat them against objects..."
Did you let the hornbill do that to you?
I was bitten by a descented skunk once. It hurt, but did not break the skin. Sorry, its the best I can do.
It's definitely the claws rather than the beak with raptors. I attended a presentation given by an Audubon Society speaker, who works with raptors, especially owls. She mentioned her experience with the power of raptor claws.
She had come back from a school raptor talk and was getting her great horned owl out of her car when she accidentally hit the garage door opener with her elbow, just as the owl had settled onto her gauntlet. It was startled and it gripped her forearm so tightly that its claws went right through the leather gauntlet and met in her forearm.
She said the worst thing was that she had to remain calm and soothe the owl so it would let go, since nothing else short of killing it would have worked, due to the strength of the grip.
In a former life as a pet shop manager I was once bitten by a cockatiel whose beak pierced straight through my thumbnail deep into the nail bed. Based on this experience I definitely would not want to be bitten by one of the larger psittacines!
Among the mammals I always found for their size rodents really pack a punch - specially if you end up hospitalised with septicaemia like one poor colleague (she made a full recovery).
Thank you for your interesting article and especially the entertaining comments.
I haven't been bitten by a bird (though I've had a vole break the skin), but as part of a course in biological field skills, we spent a day with a pair of eagle researchers. Their hands were extensively scarred, and one of them was bitten to the point of bleeding by a bald eagle multiple times in the capture session.
Also, seconded on the comments involving the talon strength of raptors. They brought a specialized pair of pliers for that very possibility.
Years back I absent-mindedly stroked the breast of a medium sized parrot (sp. indet.; smaller than a macaw, larger than a lovebird) that was tethered to an open perch in a pet store. Big mistake. Grabbed my finger tip briefly - perhaps a warning bite. No blood. Felt like I had hit it with a hammer.
Yeah, petting a parrot who doesn't know you sound like a bad idea. I did it once with a cockatoo, in a setting similar to the one AnJaCo describes, and had the luck that the bird was very friendly and in a good mood. She just took my finger playfully in her beak, keeping it there about 10 seconds, hard enough to be painful but not unbearably so. I wasn't hurt of even scared, but it served as a useful lesson, especially as the owner of the pet shop was obviously very concerned throughout the episode.
Oh, and if we are comparing with mammals: house cats bite *hard* when frightened. I had several cat bites over years, some bad (handling an injured cat who needs his wound cleaned is no picnic) and one or two very bad, deep bites which needed medical attention. Still got some scars. Of course, the fact that cats have sharp, pointy teeth adds to the damage, but the strenght also is impressive. Pinches like a vice. Also, holding the cat with gardening gloves helps limit the damage but the fangs can still bite through a not unconsiderable amount of fabric and latex.
Now, some little mammals like mice can deliver painful bites, but I don't know how much of it is the strength of their jaws and how much the sharpness of the teeth. But another mammal of similar size, a Common Shrew tried to bite me once, and I honestly hardly felt the pinch. (What was I doing? Trying to rescue the shrew from the cat...)
In the '70s I had a collection of Amazona spp, along with a pair of Lophochroa leadbeateri and a pair of Cacatua sulphurea. Getting bitten (by the Amazons) was painful and frequently bloody. If memory serves, though, the crushing strength was the painful part. The bites of my rheas and emus seemed much less than even that of domestic geese.
My only real scars from the birds were due to an emu's feet during the recapture of an escapee.
Hamster bites are fairly nasty. My brother (5 or 6 at the time) once had to be physically restrained from biting back after he accidentally scared a golden hamster and got bitten in a finger (which bled pretty badly).
Average adult male human bite force at the incisors is apparently ~400 N. Irate preschoolers presumable manage less, but that might have been little comfort for the hamster.
I have a section on my resume for "Animals I've been bitten by" =) Mammals are far and away the worst, birds the least painful. An auger buzzard did give me a nip once that made me wince, but it's nothing compared to mammals as "tame" as house cats.
I was once bitten by a 30-40 cm savanna monitor. I'm glad I was wearing thick leather gloves! It still felt like a door closing on my fingers.
Oh, I have plenty of reptile experience. I've been bitten by my chameleon (surprisingly forceful), anoles (comically futile), leopard geckos (like getting pinched, then they tend to chew), and a wonder gecko (harder, still not painful, lets go quickly).
I intend to get a small tortoise someday. I imagine getting nipped by a sharp beak would be worse.
I was bitten by an African Penguin as a child. The bite itself isn't that strong, but the hook on the end of its bill easily broke my skin and the big barbs on their tongues seemed really disturbing to me then.
I've also been bitten by a friend's Blue-fronted Amazon, which would've drawn a lot more blood if I hadn't known beforehand that it couldn't be trusted, and managed to jerk my hand away in the nick of time. It later managed to get a deep bite in on a stranger's finger. The man left with a very bloody shirt.
I had a habit of adopting every animal possible as a child, and was bitten by most of them. Turtles, fish, birds,lizards, dogs, cats, salamanders, crayfish (pinch not a bite)etc etc etc. By far the worst has been cats. Not only do you have fangs and the bite force, but what also seems like a conscious effort to cause as much damage as possible. The salamander just held on forever...no pain...just a long wait until he got bored and fell off.
And that, Darren, is why we don't let you play with the dromaeosaurs.
I've been bitten by more birds than I can probably remember including a couple of dozen species of waterfowl. For several years I had a visible facial scar where I was struck a glancing blow from the sharp edged bill of a pink-backed pelican. i agree with other posters that ducks, softbills and emu were all pretty innocuous. Tied for most painful were a cockatiel and a wattled crane. Those suckers held on. Contrary to the hypothesis above about long-billed cranes not having much force, in this particular case I clearly remember a friend having to pry the crane's bill loose from my thumb. Not broken but it certainly throbbed for quite a while. I would guess that the hornbill was just saying hello and not really giving you its best effort.
I own a bad tempered pet starling, and I can say for his bite force, it's weak as expected for a long-jawed insect eater. But he can augment his bite a little by twisting his head side to side, and then it gets surprisingly painful.
He rarely bites though, if irritated (he takes issue with people pointing at him,) he'll always jab first, to surprisingly good effect if he gets a soft spot.
On a side note, what really amazes me is his jaw opening strength. We all know starlings have specialized tendons to allow their bills to be opened with enough force to pry with, but I honestly didn't expect it to be that strong.
I got a warning bite from a parrot in a pet store. The owner was with me and had told me it was OK to pet him. The parrot thought otherwise. It just drew a little blood, but did scare me, because he didn't want to let go until the owner took his bill in her hand. Then the owner said, "Oh, he doesn't really like men." Thanks, Deb.
Then she told me the story of a wholesaler who lost a finger to a macaw. "And you can't re-attach it, because they crush the bone."
from experience I can say that budgerigars hurt a LOT when they bite. They usually lunge as a first warning, beak open, and can catch you that way, but when they want to really bite they can easily draw blood. most of the damage was done by the lower mandible pushing upwards towards the pointed anchor of the top mandible. and i always remember the keepers during the free-flying bird displays at Whipsnade saying the macaws beaks had '600 lbs of crushing pressure' and wondering just how much pressure there was in a budgies beak
And that, Darren, is why we don't let you play with the dromaeosaurs
wait, are birds dromaeosaurs?? i though they where the sister-group to deinonychosaurs but i might be wrong...
as for bird bites, the only ones i can remember are a crane and a hornbill (not one of the ground-hornbills, or was it a toucan? i can't remember...). they do bite harder than i expected from such long-jawed birds, much harder than getting pinched and enough to cause noticeable pain, but no proer wound or lasting pain.
as for raptors,i know a falconer who described her harris hawks's bites as "causing you to feel uncomfortable at worst" unless of course they stab you with the hooked billtip . raptors doesn't need strong jaws anyway as they sort of "bites with their neck" come to think of it: they stab the food with hooked billtip, secure it against the ground with their powerful foots, and then bull back with their strong neck to rip, that's where is the dammage of their bites, not in the jaws-sqeezing. vultures can quickly and easily rip open large ungulates carcasses with this technique so a weak bite force not necessarily equals weak bite: also depends on the biting technique.
it's much like sharks, who also have surprizingly week bite but do the dammage by shaking prey sideways to "saw" it with their rows of knife-like tooths.
for raptors again, i also agree with previous comments that all their power is in their foots anyway. because the hooked billtip can break relatively easily, they use their bill only to feed ,once prey is dead; only exceptionnaly to kill.
the same falconner also told me of how she once had her hand grabbed by an eurasian eagle-owl at a falconry fair: the hallux pierced the hand right trough near the base of her thumb and came out near where the three other talons where entering the hand on it's upperside. she is not faint-hearted yet she told me she was on her knees crying from it. the owl whouldn't let go so it took 3 poeples to force-open his foot. she went to hospital after that...
i also heard from another falconer in south africa that even the large eagles (golden-eagle size category)'s bites are not much painful and does not hurt, but if they squeeze your hand they will break all your carpes and metacarpes like twigs...
falcons might be a different story though: they have shorter, sturdier bills a pair of extra hooks after the billtip hook, and do use them to kill prey, i wonder if that have to do with the fact they have been concidered closer to parrots than to accipitrids at times...
pet budgies are the extent of my experience also. mine have never drawn blood, although they do seem to home in on the most sensitive spots (cuticles, the web of the thumb) and responding to the pain just gives them signals they WILL use to refine their attack.
can't hold it against them, but sometimes they have to be handled for routine maintenance no matter how much they may hate it.
I've had a common snapping turtle cut down to the bone on my finger before. I've heard stories of people losing digits to bigger turtles but never seen one first hand.
i've heard eyewitness tales of big snapping turtles biting broomsticks in two. i think i'd keep my bodily members away from their beaks, myself.
Turtle bites can be scary. My 19 cm SCL female RES almost broke the skin when it missed a food pellet, which was surprising since Spotted and Painted Turtle bites don't hurt anywhere near as much. Walde et al. (2010) mentioned that a female Wood Turtle (Glyptemys insculpta) bit a researcher on the finger and "removed a large chunk of skin and left a deep wound" - the max SCL for females of that species is only 22.5 cm.
Turtles are quite peculiar in that their bite force changes in proportion to length cubed and not squared (Hertel et al. 2002), which has horrifying implications for big snappers. Hertel et al. didn't use particularly big snapper specimens - I can't find any recorded bite forces for truly big individuals - but using their data it is possible to roughly estimate the forces involved. Assuming the largest figures apply to the same individual, their largest C. serpentina had an SCL of 32 cm, head length of 9.7 cm, and a bite force of 435 N which means that the largest members of that species, about 1.5 times longer linearly, would have bites 3.375 times as strong, so 1468 N. Their largest Macrochelys had an SCL of 22.8 cm, head length of 9.1 cm, and bite force of 334.5 N; the largest individuals are 3.5 longer (in SCL) and so could have a bite force of 14342 N, which is horrific. Of course, the head would probably be proportionally smaller at such large sizes and whatever happens in turtles which gives them dis-proportionally strong bites may weaken at such extreme sizes.
Herrel, A., O'Reilly, J. C., and Richmond, A. M. (2002). Evolution of bite performance in turtles. Journal of Evolutionary Biology 15(6), 1083-1094.
Walde, A. D., Bider, J. R., Daigle, C., Masse, D., Bourgeois, J.-C., Jutras, J., and Titman, R. D. (2010). Ecological Aspects of a Wood Turtle, Glyptemys insculpta, Population at the Northern Limit of its Range in QuÃ©bec. The Canadian Field-Naturalist 117(3), 377-388.
I've done a little wildlife rescue, and had a few bird bites - some are surprising. The biggie of course was one of the parrots, and first time I handled a galah my fear stopped me from grasping the poor thing (despite the resulting bite, its bruised wing from flipping under a car, and capture by humans that had to have left it as scared as me) tightly enough, so it was able to turn around and bite the tops of my left hand fingers HARD. The closest I can equate it to is like someone with a pair of needle-nosed pliers putting all their strength into trying to hurt me.
I was left with a half-dozen cuts or black crush marks that then went on to bruise delightfully! They're great to show off, but I wouldn't do it again :). I dealt with the next parrots a lot more seriously - haven't been bitten since.
I did hear from some other rescuers to be extremely careful around red & black cockatoos - my colleagues have called them flying boltcutters, and for very good reason - apparently a 1.5cm or so wooden dowel can be used to tempt them to bite, and once they've locked onto that, holding their beak closed over it is relatively easy (strong bite force, weak opening force and all), and I've heard tales that they've bitten right through a dowel...
The most delightful biter of my experience has been kookaburras - I've joked that trying to get food into a kookaburra initially (and they generally don't take to eating once captured, without it being pushed into them for a start) is like attempting to feed a pair of very angry scissors. As a kingfisher they have reasonably long bills, but the edges are sharp enough that when they grab hold and twist or flick side to side they can cut, especially if you get a finger in the bill close to their head. Poking just a single finger in at the tip leaves them unable to close their bill, though - and it's only a few days of care before they know food means, well, food!.
Let's not forget that testing bite force with fingers is a flawed method: you can never be sure that the bird applies full force. Crocodiles, for example, use mock bites rather often, so I am sure birds do so as well. Another example: humans have been known to crush their own teeth during seizures, but I don't think you can get that kind of force by sticking fingers into their mouths :-)
Has anyone been bitten by one of the large African vulture species?
It would be fun to have a scale for animal bites just as there is for the heat of chilis and for insect stings.
How in the fuck does that work??? How do they cheat basic physics???
My bird bite experience is only with Quaker parrots. Specifically one Quaker female named Scooby. She can be a feisty little girl. She can draw blood as well as take a hunk of flesh when in the mood. Luckily she is rarely in that mood. Interestingly enough, she modulates her bites depending upon the message she wants to get across. There is playful "beaking" with nearly no pressure all the way to full out war.
She will also hiss like a little green lizard to warn people away from her property. Which is what ever she decides she owns.
Oh, if noone else is going to say it, I will:
"My sister was bitten by a moose! No, really!"
Worst bite effect I have ever observed was a domestic goose bite to the butt. I'm not sure if it was the pain or the indignity that propelled the victim a couple of feet into the air with a loud shriek, but it was impressive.
The goose was an aggressive panhandler, and known to peck and nip at people to encourage them to hand over the goodies.
When I did survey work for Operation Wallacea people who worked with both reckoned that mammal bites, size for size, were worse than reptiles.
Looking at the list of injuries here, I would suggest chain mail gloves (like butchers use) if you care about your fingers.
I've been bitten by a wagtail and a blue tit. Both were almost comically weak, but at least they tried. Got to appreciate someone for aggressively attacking someone 1000 times more massive. Common lizard (Zootoca vivipara) has a similar bite, though with tiny but sharp teeth.
Rodents are the creatures I don't want to mess with. Considering their size they must have pretty impressive bite force. I was recently bitten on the knuckles by a juvenile field vole, and an ice pick is a pretty good analogue. My former roommate had a pet red squirrel. It had the nasty habit to sit on a wardrobe, and when someone walked underneath, jump right on the poor victim's head, run down on the wrist and sink it's teeth in some soft part so that the upper and lower incisors met under the skin. It hurt like hell. Then it would just run back up, jump on the wardrobe again and look far too satisfied with itself while the victim was looking at a rapidly expanding puddle of blood. It was an evil little thing.
On the other hand, my (now long dead) pet rat could bite very gently to warn me, if I was doing something it didn't like (such as cleaning it's nest). It was just enough to break a bit of skin, though it would have been well capable to sink its teeth to the bone.
#30 Adam F: Now that you tell how a monitor lizard bite feels, I'm actually happy I didn't catch the young Nile Monitor I was chasing while in the Gambia. It was around 40 cm long, and I almost got it... with my bare hands. Ouch.
Around two weeks ago I was bitten by a chicken at the finger. It was not painful at all, only very unexpected. I have also experience with fire salamander bites, they also donÂ´t hurt. Once I had my finger inside the mouth of a living carp, really a strange feeling.
ItÂ´s sad that Steve Irwin is no longer alive, he was bitten by incredibly many animals.
Strange that nobody seems to have mentioned being bitten by shrikes which are generally acknowledged by Swedish ringers as being the nastiest of the frequently ringed birds to handle, having a quite powerful bite and using it freely.
Personally I think the worst Swedish bird to handle is probably the heron, it uses its bill as a spear and usually aims for the eyes. Large raptors can also be very tricky, particularly Goshawks and Golden Eagles. In both cases it is the feet that are dangerous, not the bill.
The most amusing thing I've been bitten by is a pet rock dove. The little guy (definitely male) enjoyed fighting. He would peck my hand, grab a fold of skin, shake it like a bull dog, and play tug-of-war. Yes, a pigeon. Since he didn't break the skin, it was quite amusing for both of us.
Years ago a bird-bander friend emailed me the story of a woman who used to kiss birds after she banded (ringed) them and before she let them go. If I recall the story correctly, she was left to band a shrike, the last bird from the net run, while everyone else went back to the nets to get the latest birds. They sternly told her, before they left, not to kiss the shrike. She didn't listen, so when they all came back from the net run they found that the shrike didn't like being kissed and was more or less hanging from her lip. They eventually separated the two, and let the shrike go, but I think that took some doing.
My bite experience is mostly my cockatiel. Most of his bites are pretty weak, but every now and then he'll make an attempt to bite hard (usually when riled) and it'll be like a hard pinch. Never broken the skin, though.
I was also bitten by a pet gerbil as a child. I was handling it a little too roughly and it whirled around and sank its teeth into the tip of my thumb.
Was an animal care specialist for a major pet supply chain for a number of years. The larger Pionus parrots can mess you up was gonna face the music and trim the nails of a Pionus that was very shy about her feet. I held her while a co worker who was also a vet tech trimmed the nails. I never let go though this was one of the most painful experiences I ever had. I was bleeding from several swollen cuts. Blood everywhere! My hands were so swollen the next day I could not completely close them, And this is from a bird only about 50% bigger than a sun conure. After that, I spent a lot more time taming the burds to haaving their feet restrained and used a cordless Dremel grinder.
I was also bit and battered by two Mexican whistling ducks (fulvous tree ducks?) when I was trying to reescue their baby who had fallen into a cofferdam on a water hazard at a golf course. Retreated after first attempt as they attacked my eyes. Crept on my belly awith one arm over my face to complete rescue on second try. Unable to get to my eyes, they tried to puncture my eardrums. but their bills were too thick to get all the way in. Hurt like hell though.
I once saw a headline claiming that a platypus sting was 'more painful than shrapnel'.
Could we do a proper test of that after we've done the bite strength thing?
I can attest to the extreme painfulness of the bite of the American Kestrel (Falco sparverius). This probably is more a reflection of the needle-like sharpness of the bill tip than of bite strength per se, but repeated bites left my finger tips looking like a pin-cuchion and ached for days afterwards.
I was bitten just yesterday (after reading the post) by my daughter's Rainbow Lorikeet. He's never given me much more than a pinch before, but this time sunk the bill tip right in about 5 mm. We speculate he's recently become sexually mature and developed a strong gender preference, or perhaps it's a 'what have you done for me lately?' thing, because I've been feeding him less often as the owner-of-record gets less forgetful.
There are many venomous snakes that I'd rather be bitten by than a parrot. I could list a few, some other time.
I was bitten by a Bald Eagle once while I was restraining it for medical treatment. It was not bad, certainly not bad enough to convince me to let go of the legs, although the point, which did not break the skin, did get my attention.
Parrots of any size are much larger, although a shrike which was trapped in my garage probably drew the most blood and hurt the most-ungrateful little b-----d! I suspect pet parrots at least usually restrain themselves somewhat, but that little shrike did not hold back, and used the toothlike notch in it's beak very effectively.
The Crested Shrike-tit in Australia was credited by John Gould with giving a "very shrewd nip", and according to bird-bander folklore, takes a thumb-nail off with no trouble at all. It has a notched bill in profile very like a falcon's - hence scientific name Falcunculus cristatus. It uses this to peel back from Eucalypt and wattle trees. The bill is quite narrow from side to side and the bird can slide it sideways under the bark edge and turn it up to vertical, prising the bark away from the trunk. The curve of the beak is very like a claw-hammer. The neck muscles must be very strong.
I also recollect seeing a TV documentary in which the narrator (not Attenborough)stood by a Red-tailed Tropic-bird's nest and said how privileged he felt, etc.. I had once seen a tropic-bird's skull, very like a Caspian Tern's, but with great sharp ridges across the palate for holding fish, so I was expecting trouble. The man then picked up the bird and tried to continue the script while his hand was savaged. Lots of blood. To his credit, the bird was not injured as he put it back and detached himself.
Bites from European Jay and Hawfinch hunt like *** Both leave you black area for two weeks or so.
But, as others pointed, most birds stab (peck) or hit the prey to the ground or branch, rather than bite. Interestintg example of saving weight on jaw muscles by using muscles moving head and neck for killing the prey.
Coming to pterosaurs - if Q. northropi simply raised its head and bring the beak tip down at full speed, it would kill a man-sized creature. Otherwise, picking up and hitting to the ground would finish the job.
Actually, bite force may be meaningless in discussions about terrestial stalking/otherwise for azhdarchid pterosaurs. Everybody agrees azhdarchids ate some animals, terrestrial or aquatic. Is killing a terrestrial animal any different from killing an equally sized fish?
Re: bite force of terror bird Andalgalornis.
This bite force is indeed small. Anybody knows how powerful were its legs? Maybe phorusrhacids killed prey primarily by kicking/stomping, being secretarybird analogues? BTW, secretarybird seems not to have striking adaptations to its killing mode, and is a bit neglected in discussions about lifestyle of phorusrhacids/small dinosaurs/pterosaurs etc.
Re: mammal bites, I'm rather surprised that no-one's mentioned bites from H. sapiens. I've been bitten by numerous things but the only time I needed hospital treatment was when my little brother bit me.
I was 6, he was 4; I don't actually remember the incident but it passed into family folklore.
About 2 years ago, I visited an ostrich farm that also had a bunch of Nandus (Rheae).
The guy running it basically explained that for us visitors, the important difference to keep in mind was that while ostrich bites are usually painless (they just pick up anything that's bite-sized and quickly let go once they realize it's resisting being gobbled up), nandus are more inclined to eat moving prey - and if they happen to mistake your finger for a worm, their bite usually involves some rather painful twisting and pulling.
FFS, haven't you people ever heard of freaking gloves?
I've caught probably a hundred royally pissed-off (they always are) snapping turtles but I know enough to always handle the non-business end and have never (quite) been chomped.
I have been popped when bleeding sliders and that can both hurt and draw blood. Probably served me right; turnabout is fair play.
They were lying.
What exactly are the 'basic physics' connecting body length to bite force? Please explicate.
The thing here is, several variables are confounded if you're comparing bites by pain.
1) bite force (newtons of force generated by the jaw muscles on the lever of the jaw)
2) sharpness of the biting surface (duh, cat teeth hurt)
3) gape (re-learned this just this morning from a fledgling crow: a full bite of a finger is nothing, but a pinch of skin between the very tips can hurt like hell)
I have been bitten by cockatoos, but I assume those were just warning bites, still very painful. I have been bitten by a cassowarry, and contrary to emu bites, it broke the skin and hurt quite abit, but I think maybe because it was moving its head quickly. Unless of course cassowarries are stronger biters than emus? I know both occasionally dine on small animals, but I always assumed these were either swallowed whole or beaten.
@farandfew #59: A while back I designed a familiar (a companion animal with a few fairytale upgrades, such as being extra smart and eventually learning to talk) for a magic-using character in a Dungeons & Dragons game. I decided to use a platypus as the base creature. Converting the real-world abilities of the platypus into D&D stats produced a creature so dangerous that I had to downgrade it to keep it from unbalancing game play.
Oh, body length? I thought actual muscle size. If they manage to increase their jaw muscles proportionally to the square of body size, it's not surprising... do they?
Muscle force increases with the cross-sectional area of a muscle. If all else is equal, that area increases with the square of the length of the muscle, and that tends to be directly proportional to body length.
Of course, not all is always equal. But jaw muscles increasing with the square of body length are a bit hard to imagine.
I have been bitten by a Green Iguana - and have the scars to prove it - it got me on the 3rd and 4th finger and actually severed the dorsal tendon for the terminal phalanx of digit 3. For an herbivorous animal they have a nasty bite. At least you don't have to worry nearly as much about bacterial infection as you would with a varanid.
Oddly enough, I was just today bitten by a California kingsnake, and can report that it wasn't very painful, though the little devil held on very tightly and wouldn't let go until he was dunked in a bucket of ice water. His tiny little teeth just barely broke the skin, leaving no bleeding but a bunch of little red dots.
Darren Naish: Paleontologist, Tetrapodologist, Freelance Writer and Chew-toy.
Or venom. I'm surprised green iguanas have such a powerful bite. They eat plants, for pete's sake.
Re: domestic cat bite strength
The family's ten pound housecat has (for no reason we understand) shown that she can bite straight through aluminum cans. She can only do this up at the edge where there's any chance of grip, but it is sort of impressive.
The birds that have caused me the most damage aren't listed here. Cormorants. They have an excellent ability to reach further than you expect and bite your arm. Then they twist. Gloves don't work too well because raptor gloves are too thick and my hands aren't dexterous enough and light weight gloves are too short and the corm can reach above them.
I had a similar problem with large gull species (California gull, Western gull). Could never find gloves that allowed the fine motor control I wanted with protection of my arms.
Never been bitten by a raptor but I'll agree about the cardinals. They're nasty. And I knew a (domestic) duck once who knew how to pinch and twist.
Sadly, despite years of handling wild and exotic animals I don't have interesting scars or stories of being wounded. My scars have all come from domestic cats!
I owned a Burmese python from about 18 inches to six feet. Getting bitten by the baby was cute. Getting bitten by the larger version (not yet an adult, they get much bigger) was not fun. A friend who was a snake owner recommended keeping a bottle of vodka or some other alcoholic beverage close when removing her from the tank. (That was the only time she struck, thinking it was feeding time. Once out of the tank she was quite docile) If the snake latched on, you poured a trickle of the vodka down the affected limb so that it would enter her mouth. Immediate release. Never failed. When I finally gave her away she was still in perfect health and showed no ill effects from the infrequent cocktail.
Regarding the prey-killing-by-shaking possibilities of azhdarchid pterosaurs, I was reminded of what my friend, a whippet breeder, told me about how they caught and killed rabbits. Apparently, they intercept the rabbit at speed, grasp it by the neck or somewhere along the spine, and then do a somersault, which breaks the spine of its prey by using the animal's own intertia.
Another possibility might be to intercept the prey at speed, lift it a fair way into the air, and drop it.
PS My God, you people have all been bitten a lot!
Apropos of all this, roughly, I was reminded recently (by seeing the tooth marks on my hand) that snakes have prominent palatal teeth. And while looking this up I came across a nice paper that describes the distribution (in two senses) of palatal teeth within squamates. This:
Mahler, D. L., and M. Kearney. 2006. The palatal dentition in squamate reptiles: Morphology, development, attachment, and replacement. Fieldiana: Zoology 108:1-61.
Linton zoo?? I missed the clouded leopard they had there. Sad times.
I was bitten by a full grown macaw on the forearm in a pet store once. It felt like the most intense nip ever- didnt draw any blood or leave a mark but jeez it hurt for hours afterwards. my brother was able to put his finger in its mouth where it would gently close its jaws around his finger and would lick the salty sweat from his digit. i'm guessing the very tip of a macaw's beak is where the most powerful bite lies as my brother would place his finger nearer the mouth away from the tip of the beak and i was nipped by the very tip.
John H, your link seems to be broken; but that paper and others can be found here: http://www.oeb.harvard.edu/faculty/losos/mahler/Publications.html. I'd somehow missed seeing it before (spotty library access to that particular journal) but it looks like a useful review.
Surprisingly enough, the Myiarchus flycatchers can be somewhat painful--and they constantly try to bite as well. Worst in my experience is Brown-crested (Myiarchus tyrannulus). Vicious.
Speaking of flycatchers, I've also noticed that the different Empids have slightly different bite strengths. I've sometimes wondered if that might aid in species identification, but of course it would be absolutely worthless in the field.
Other things I've noticed in my banding career:
Roadrunners hurt. A lot.
Summer Tanagers also have a strong bite--interestingly, Western Tanagers do not have nearly as strong as a bite to me. I've never had the chance to band a Hepatic tanager, but I imagine they'd be marginally more painful than a Summer Tanager.
Western Scrub-Jays are also mildly painful. Steller's Jays are not. In fact, Steller's Jays are really docile. We've never caught any Ravens, they're just too smart. Oddly enough, though we've caught Green Herons, we've never captured a Great Blue Heron--and they're equally common where we banded. (though once we had one plucking birds out of the nets for lunch. One of the oddest things I ever saw)
Yet topping the cake are grosbeaks. I was bitten in the nose by a Blue Grosbeak once. Nobody warned me when I started banding that I'd have to worry about something like that. Northern Cardinals are also pretty bad, but not nearly as painful as a Black-headed grosbeak. I banded a male once, who wouldn't let go during the whole banding process. Two weeks later, I still had the bruise on my hand.
More amusing are Verdins, who attempt to be vicious and bite your fingers, but just end up looking absolutely adorable because they are even smaller than Chickadees.
"A lot of people who do hands-on work with animals have neat wound"
I had a pal whose brother did yome voluntary work in a zoo and reportedly had one of his nipples bitten off by a sloth (through the T-shirt he was wearing). Never saw the (abscence of) the nipple though, never even met the guy, so it's purely anecdotal.
This is the best comment thread in the history of the internet.
Toucans bite at the tip is negligible, but they know that and will try to maneuver your hand to the hinge to improve the mechanical advantage.
Red backed voles bite hard and then hang on, much to the general merriment of your 5th grade audience.
In my youth I rescued a baby owl that was being bombed by crows. I had enough sense to put on leather gloves first. It's talons pinched hard through the gloves.
A local trapper told of releasing a house cat from a leghold trap. It climbed up one leg biting all the way, spent some time around his face and the exited via his other leg. He didn't walk right for some time.
As far as animal bolt-cutters go, may I suggest a stone crab?
OK, well, I'm not a scientist. But, when I was a child my family had a Mexican red-headed parrot (at least we thought it was one). It had been passed down the generations from my great-grandfather and died well into its 70s. The parrot was, of course, named Polly. Polly was a fun bird, constantly imitating the noises emitted by crows, chickens (presumably my great grandfather's chickens, my parents had none), and also a demonic human laugh. Polly was very fond of bacon and, occasionally, of the fingers of humans he liked, which he'd bite for no obvious reason. He liked to have the top of his head scratched with one finger. Most of the time, this was a pleasant human-parrot bonding moment. But, on occasion, Polly would put his head down, the human would advance the finger--then, WHAM, a bitten, bleeding finger! Followed by the demonic laugh. I don't have any scars though.
I once put a finger through the net of Rhinoceros Hornbill aviary. The male jumped close and I had enough sense to quickly move the hand away. WHAM! He stabbed through the mesh with such a force that the noise of vibrating mesh went all around the house.
Had this Ground Hornbill not grabbed you but pecked with full strengh, Darren, you would type with one hand for couple of months, minimum. Which of course would make our blog experience a lot worse. :)
RE snapping turtles--my grandpa used to catch snapping turtles and bullfrogs to eat, half a century ago. This entailed bringing them back to his house and letting grandkids watch the process in amazement. He caught a monster snapper once, and brought it back home to his basement. He proudly showed me how strong it was by sticking a broomstick in front of it. WHAM! Broomstick broke cleanly in two! This made quite an impression on me.
PS Big bullfrogs can also do damage, though not by biting. My grandpa kept a massive newly caught dinner candidate in his bedroom in a 5 gallon bucket with a pane of glass covering it. The bullfrog jumped THROUGH THE GLASS!!! It shattered in many pieces, much to the horror of my grandma, who did not appreciate a giant bullfrog loose in her bedroom.
I've heard enough horror stories as a birder about parrots and other pet species doing serious damage (nipping off earlobes, gouging cheeks, lips, etc) by accident that I don't think I'd be brave enough to stick my finger in the beak of a bird with bill an order of magnitude larger. Good on ya!
Though the bites I have scars from are all reptiles. Both from iguanas (bite, scratch and tail-whip scars) along with bite scars from garter snakes... but I never really made the connection between bill shape and the physics involved in closing them.
Yesterday I got bitten by a 4-cm-long grasshopper nymph. Impressive power, but didn't break the skin.
You know that the bush-cricket Decticus verrucivorus is - in English - called the 'wartbiter'?
I had two geese, one of them chinese, when our kids were toddlers. One goose, named "Lucy" was sweet tempered, and walked along side my boy, nibbling at the rivets on his Oshkosh B'gosh overalls when he plopped down on the lawn. The other, named "The Bastard" would attack when opportunity presented itself. I wore high topped boots, but he learned to bite me on my knees when I went out to feed him. Perhaps bite is just as much a function of temperament as physical structure. Come Christmas we found out he really was a tough old Bastard.
Severed soldier-caste army ant heads are used here in Amazonia to close wounds. They bite and don't let go, even after the body is removed!
I didn't know about the wartbiter... doesn't verruca mean "wart"? :-)
I have plenty of reptile bites. Chameleons are surprisingly strong; leopard geckos, colubrids, rhacodactylids are all kinda off the radar. Savannah monitors are like a vice, baby Argus monitors have bites that itch for a day or two afterwards, and large snakes feel like you're getting punched.
No wonder. They're venomous.
A friend of mine left primate studies (chimpanzees) and took up dog work when she realized that *all* of her more-experienced coworkers had lost digits to the creatures.
She has been bitten many times by many kinds of dogs, including some fairly serious attacks by pit bulls and german shepherds, but still has all her senses, limbs, and digits.
I can corroborate the comments on cat bites. My cat bit through the joint capsule of the proximal interphalangeal joint of my index finger (I picked her up after she'd been attacked by a dog). Ouch. Prompt ER visit and antibiotic injection prevented any nasty sequelae.
Incidentally, this whole thread reminds me of the Rev. Nathaniel Martin in the Patrick O'Brian books....
My experience is mostly with birds: small finches (zebra's, for example) can have a suprisingly strong bite, but are not usually painful. It's the common housebirds you have to fear: I used to have a budgerigar that was capable of latching onto your finger so hard you could then lift it up and walk around the room with it dangling by it's beak. (twice I ended up accidentally throwing the poor bird across the room when it grabbed my finger and caused me to jerk back). Cockatiels are even nastier if they want to be: if you own a cockatiel that doesn't bite hard, it's solely because they like you.
Lorikeets or Rosella's, and other med-sized parrots, will take a large chunk out of you.
Pigeons, chickens and many other birds with similar beaks don't usually bite, but they can peck. It's usually enough it startle, purely because you're not expecting it. Rarely does any damage, though.
And cockatoo's are terrifying. Beautiful, but terrifying.