How do I 'tame' my growly, snarly, excited puppy?

[ValeVengaVamos]

We have a 12 week old labrador puppy - he's lovely and generally very good, except when out in the garden! It's another few days before he can be taken out for walks but we have a large garden where he can walk on the lead/play. It seems that when he starts running in the garden he gets very excited, and then turns on whoever is with him and starts growling/snarling and jumping at them to bite them. It's quite scary because he is quite big for his age and he's so full of energy that you hardly get a second to recover between lunges. How should we deal with this?
When I take him out into the garden I have started always carrying a toy that I can give him to chew when he gets overexcited to try to divert him from biting/lunging at me. This usually works to calm him down somewhat, however this afternoon he was the worst yet and the toy technique didn't work. He was relentlessly biting, barking at and scratching me, leaving cuts on my hands and arms, and hanging off my top, which nearly ripped. I could barely get away from him because by the time I'd taken a step away, he was running at me for the next bite. It was really quite frightening, and I'm worried about taking him out in public in case he does it to someone else!
He thinks it's a game and is not being deliberately aggressive, but obviously we don't want this behaviour so any tips would be much appreciated!

Welcome to the zoomies!

It's totally normal but, as you say, not desirable. In my experience, it happens when they're over-excited and need a nap! Think of them like toddlers - they don't know when they're too tired, so you need to try and pre-empt the madness and get them down for a nap before they get over-tired and silly.

At 12 weeks he should be having between 18-20 hours of sleep in a 24 hour period, so I would make sure he gets plenty of naps and try and work on calm games rather than excited play with a toy.

So, when he gets silly, instead of continuing to play with him, pop him in his crate or pen with a nice frozen kong or a natural chew. Chewing is a naturally calming action (as is licking, so you could try a licki-mat too) and once he's finished his treat, he should settle down and go to sleep.

Like PP, it always surprises me how much sleep puppies need, like newborns! I'd keep play sessions short and sweet and at the very first sign of over-excitement stop playing/interacting at once (stand up and turn your back if need be) and take him inside for a rest - do you use a crate/pen or does he have a bed? If so get him to settle there - he'll probably normally drop off but if not just use it as a bit of a time out and then you can go back outside for more play/training. Try not to worry, this sort of over-excited puppy snarling/growling/biting is done in play not in earnest and although it sounds alarming is quite different to 'real' aggression - just look at how roughly pups and adolescents play with one another without ever actually hurting each other or 'meaning it', and at this age they haven't learnt that they can't play with humans in quite the same way, so quite/calm removal from the fun situation and plenty of rest is the way to go...

Totally agree - nap time! Ours gets cranky when over tired but we can now pre-empt this with a quick time check. If he's been up anything longer than two hours, max of three, chances are he's overtired. I was really surprised just how much he slept between 8 and 16 weeks. Envious, almost .

For the biting, I read loads on this when mine was doing this as a puppy and one method I tried and found effective was to make a loud ouch or squeel and say No when he bit and turned my back and ignored, essentially "not playing" anymore. Apparently they learn this way with litter mates, if the play gets out of hand or they hurt each other.