Two cats

Question
QUESTION: For approx two years, my mom and I have owned a very lazy exotic short hair and for two years he's been happy with the dogs as companions and would even groom them while purring. This changed when my mom saw him latched onto one of her bird cages and started shutting the door and training the dogs to attack the cat whenever he got too close to the birds and to keep the door to her room (and where the dogs usually were) shut at all times. My poor cat got pretty lonely and turned to me for company and I didn't mind. I left my door open for him while I was home and shut it when I had to go to work so my own parrot wasn't left alone with him. But I work full time so he's alone more often than not unfortunately.
Earlier last week my mom convinced me adopting another cat was a good idea. After some looking we found a cat just as lazy as ours and seemingly good natured enough. This new cat is 5yrs old and was almost euthanized once before being taken on by another adoption agency. He spent a few days in our spare room to get used to everything and I would let him out to explore while supervised. My cat was of course curious and spent every moment sniffing the new cat and the new cat didn't seem to care about my cat doing so; so I eventually let the new cat wander unsupervised.
Until yesterday, I notice my cat starting to lose weight and started to watch, he wasn't eating anything because the new cat (just as fat as my own) was eating BOTH bowls of food! The new cat is also a lot more aggressive in trying to get my attention than my poor kitty; so after some thought I decided I jumped the gun on the new cat being unsupervised and put him back in the spare room with child gates so he could still see out and get used to the world. My mom saw what I did and decided that was the sign to throw in the towel(her idea of getting the cat acclimatized to a new environment is to throw something or squirt the cat when it growls or hisses). We've barely had the cat a week and I'm not quite ready to give up on this fat ball of fluff.
What else can I do to help my cat and the new cat get along without the new one absolutely dominating the other? I have put their food on opposite sides of the gate so they eat together and when the dogs are out, this gives the new cat a chance to examine the dogs without the need to hiss or growl. Am I even doing the right thing by trying to make this work?

ANSWER: That's actually not a bad idea to feed them like that. Do they actually eat "side by side?" I'm more curious about the bird situation and change in behavior in the first cat. Have you always had birds with the cat or has something changed with the environment/situation to cause such a sudden behavior change?

But lets also focus on the two cats getting along. It's great that you didn't have to deal with physical confrontations. The one thing that always works for me...sometimes more time than others...is using a favorite food or treat and I like using either canned food or tuna. The goal of this process is to have them start eating peacefully as far as apart as room allows and begin moving the food dishes closer together until they are eating side by side. This works to show the cats that they can both exist peacefully in the household.

If this ends up not being an issue and it's more of a point of the second cat just wanting to eat all of the food, then I would schedule in routine feeding times during the day and feed them in separate areas similar to what you're doing right now.

On the note of your mom, it is a good idea to have a spray bottle handy in case a physical confrontation starts, but not just because the cat growls or hisses. You can also use a noisy or loud toy to toss across the opposite side of the room for distraction purposes.

Let me know how things go.

---------- FOLLOW-UP ----------

QUESTION: The cat's immediately ate "side by side". Both are fat fluff balls so they really don't care where they eat as long as the do. The closest thing to a physical confrontation they've had was my cat trying to play (his idea of play is to pounce on the new cat kinda like the dogs do to him) and the new cat didn't like that so much so both lost a couple clumps of fur but that's about it.
The dogs are still touch and go but he doesn't growl or hiss at them. He swats on occasion but that's about it. I still haven't set up a scheduled feeding time but that's because I keep putting it off. In the meantime I have one large bowl of food and keep pulling the new cat to the edge of it so he shares with my cat (after a few tugs he got the idea and stopped eating from the center).
The bird thing is somewhat new. We've had birds longer than we've had cats and it was only after my mom bought my cat a scratch post with a feather toy on it (I tend to avoid toys with feathers because I really don't want to encourage the instinct to attack feathered things) and that just under a year ago. As for the food thing, I actually got the idea from a tv show called "My Cat from Hell". Lots of useful information on how to deal with cats.
I do have a new question. My new cat keeps pulling the collar off my old cat (it's just one of those collars that detaches when tugged on to keep the cat from getting strangled) and then runs off with it. What is going on? Why is this cat so hell bent on taking my cat's collar?

Answer
As far as the collar goes, it's a new play toy for the new cat. Do you have a collar on this cat as well? That might bring in a new level of awe.

Just an inside of a cat's brain; it's great that you try to avoid things to not bring on new behaviors, such as feather toys- however it really is in the cat's blood to hunt birds, but I do think that the feather toy definitely perked up the situation.