flesh grazing theropods

[andrewsaurus rex]

an intriguing concept whereby meat eating dinosaurs bite chunks out of sauropods, feeding on them, without going through the bother of killing them, a la the cookiecutter shark (a 2 foot long critter that preys on big whales and other large animals).

I wonder about the effectiveness of this strategy.  On the one hand, it seems a nifty way of getting a meal with lesser risk..no need to try and kill a big animal, just take some nips out of it until your belly is full.  Lower risk and no waste of meat as even a pack of theropods would have trouble consuming an entire full grown sauropod before it rots.

On the other hand, the strategy would require many biting attacks, as one mouthful would not be a full meal.  And those mouthfuls would probably be somewhat on the small side as it would surely be more difficult to bite as big a chunk out of a living, moving animal as a dead one.  And is the risk lower?  Several close in biting attacks, mean repeated exposure to the sauropod's tail and legs, any of which could inflict lethal injury with ease.

Now perhaps the theropod could dash in take a nip and dash out before the suaropod even felt pain....after all, when we stub our toe there is  a delay of a couple of seconds before it hurts.  A humongous sauropod would surely experience a significant delay between infliction of pain and feeling it.  Perhaps enough time for the theropod to move out of range.  However, we humans have a reflex, which I think is at the base of the spine, that causes us to react to pain before we consciously feel it.  It's why we pull our hand back after touching a hot stove before we even know we've touched it.  Sauropods probably had similar reflex nodes all along their spines, otherwise they could have part of their tail eaten off before they were even aware what was happening.

So while flesh grazing would certainly be less risky than trying to bring down and kill an adult sauropod, was it less risky enough to justify the use of the strategy?

Maybe a better idea would be for the (pack of) theropods to give a few slashing bites, back off and let the nasty bacteria that live in their mouth do most of the work for them.....just keep following the inflicted sauropd around for a couple of days until it drops from infection and then dig in!

[stargatedalek]

Frankly, I think this is a fun idea but ultimately an inherently flawed one. I could see a little pterosaur biting chunks off of sauropods, but not large theropods.

The biggest issue is one of risk, as you said the theropod is in a lot of risk just getting near a sauropod, let alone doing so multiple times and in a way that would definitely make the sauropods extremely upset and like to defend themselves. But less obvious is the risk to the sauropods. Cookie cutter sharks are not about to accidentally kill a whale, but sauropods could easily die from infections or even bleeding out because of these attacks. When you accidentally kill your buffet that causes issues with the viability of your hunting method.

All of this comes from a desire to justify the seeming presence of sauropod hunting anatomy in large theropods, despite the ridiculous notion of them attacking adult sauropods even in packs, but ultimately that is an unnecessary goal.

The largest carnosaurs raised their young for upwards of ten years. Sauropods produced eggs by the dozens if not hundreds and may not have protected them after hatching at all or if they did it was only in allowing the young to travel alongside them. That is a huge disparity in investment, but also in population. And sauropods were far from unique in the strategy of flooding the ecosystem with young.

It would be foolish for carnosaurs to risk their lives attacking adult sauropods, even as a pack, but why bother? There were thousands of young sauropods being introduced to a region every year. There is no reason to hunt adult sauropods, when sauropods of various ages were probably extremely common, and in this manner they likely hunted sauropods in relatively straightforward and traditional ways.