First off..yes you should be concerned about food aggression. Guarding behaviour is often rooted in anxiety (as in anxious about losing it) and can escalate to more severe and varied guarding behaviours.
As for taking an object away and then giving it back, well. Think about it this way..if you were eating an ice cream cone as a child and your parent came up and took it away from you, no explanation, waited to see how you reacted and then gave it back to you..how would you feel? Would you, the next time your parent approached, try to keep the cone away from them? Say no? Get upset and cry? Regardless of "getting it back" you are STILL taking it away with force and without input from the dog.
Now..before I get the whole "anthropomorphism" argument thrown at me, dogs brains and human brains are basically the same, dogs with a smaller cerebral cortex/frontal lobe. Emotions between the species are organized in the older part of the brain..so feelings CAN be related.
Food may not seem as a life or death situation..but in reality it IS. It is a primary need, food and water rank number ONE on Maslov's hierarchy of needs and lack of these two things means certain death.
Behaviourists recommend NILIF and hand feeding, putting up the dishes when the dog is done it's meal and working on a TRADE up for any item you may need to get from your dog. Working on training a "drop" command by trading (rewarding the release of the item/food) and working on a "leave it" to prevent them picking up unwanted items in the first place works well and does not set up an "I WIN you LOSE" situation.
I worked with a beagle mix that started out guarding his food and escalated to guarding the kitchen, the hallway, the bedroom etc and bit his owners repeatedly because they insisted on confrontation, equating the relinquishment of the item as respect. They found out the hard way that that wasn't the way it worked. We instituted NILIF, started working on trades, removed all high value items in the beginning and got a DAP diffuser to reduce anxiety. I gave them step by step things to do if he managed to get something or be on the couch (which he guarded) without forcing him off (and causing a bite). Six months later, no bites, the dog is happy to hang out on the living room rug, stays outside the kitchen while food is being prepared and sleeps happily in his crate. He is not "cured" of the behaviour and likely never will be (8 years of confrontation and practicing of the behaviour takes a long time to overcome). If you deal with this NOW by taking away his "need" to guard by reducing his anxiety about it you will not see the kind of escalation this client experienced. On this subject I highly recommend the book "MINE" by Jean Donaldson.
As for the growling. I personally never recommend punishing a growl. EVER. The reasoning behind this is if I take away this very first, important form of communication and do not respect this communication it will extinguish the behaviour completely, regardless of situation. The dog doesn't learn "now it's okay to growl" and "now it's not"..they just stop it. Period. This is a dangerous thing. This doesn't mean you don't work to figure out what the growl is about, is it pain, discomfort, fear or guarding behaviour and then working on desensitizing the dog to what it is bothered by. A dog that has had it's growl taken away skips right to the next step..no warning. Yikes. Growling is not disrespect, it is a communication and one of the only ways he knows HOW to communicate his uneasiness or discomfort. If you do some research on body language and calming signals you would be surprised how many more body signals and communications are given even before the growl, but most of us, without having them pointed out to us just don't see them.
I'm on a roll so I will continue about the dog park.
Young puppies (under five months) can find the dog park overstimulating and there is always the risk of non puppy friendly dogs. Daycare is different. There are staff trained to watch the dogs behaviours AND ALL the dogs are assessed before becoming "guests". Anyone can go to a dogpark. If you can go during slow times or know of other puppies that go that you can keep separate from the adults that is another thing..but I have seen many a young pup turned reactive by being attacked by a non puppy tolerant dog.
Good puppy classes, play dates with other puppies etc are a great way for socialization and communication skills to develop without putting your pup at risk.
Well, that's my fifty cents worth.
Good luck with Waldo!
