I adopted a dog named Clover in January. She's eight-years-old, very sweet and calm. She lived in a foster home with cats (and other dogs) and apparently never had any issue with them at all. I adopted a cat and brought her home last Thursday; she's also eight years old, has a similar energy level, and overall seems very compatible with Clover on paper. I've been introducing her to Clover in small doses, and so far Clover seems to just be getting worse around her rather than better. At first she just seemed uncertain and tense. Now she's actively lunging and snapping at the cat to make her go away. Snowbird, the cat, is very sweet and hasn't shown any aggression in return. I have her set up in a spare bedroom. When I let her out to explore, there's always a baby gate on the door so Clover can't enter and she has a secure place to run to. When Clover lashes out she just runs back there or to her cat tree in the living room.
Clover never chases her and doesn't seem to want to hurt her. She just wants Snowbird to go away and she calms down immediately after Snowbird responds by leaving. For what it's worth, she's only done this a few times and they've had more good interactions than bad - they've been fine relaxing on the couch on either side of me several times now - but the bad interactions have been more recent and I don't want them to keep happening.
To me it seems more like anxiety than anything else - Clover's generally anxious in new situations and doesn't like things that are unfamiliar to her. Often when we go out, she'll cling to me a bit or hide behind me if a stranger comes over to say hello. Maybe she's upset that Snowbird is approaching me at a time when she's usually looking to me for comfort? I'm not sure what to do to get Clover to relax around Snowbird; I don't need them to be best friends but don't want Clover to feel threatened or for Snowbird to be chased off. I'd like her to feel at home here and hate that she's spending lots of time in the spare room rather than out here with us. This is my first time having a cat (I've always had dogs and my previous dogs wouldn't have been on board with a cat at all) and I'm worried I'm going to do the wrong thing and make them hate each other. I love Clover so much and Snowbird is such a sweet cat. I really want this to work out. Since they're not fighting or hurting each other, do I just try to let them adjust in their own way and avoid intervening as long as things aren't escalating? Or should I go the other way and make things more controlled and/or not let them be around each other for a while? I really can't see this becoming a dangerous thing as far as their physical safety - neither seems interested in fighting - but I don't want them to stress each other out to the point where they never get along. I don't want to make this worse.
If it makes a difference at all, Clover's a small dog - not that much bigger than Snowbird. I think she may be a little intimidated by the fact that Snowbird is at eye level or sometimes above eye level since even as an older cat, Snowbird is very agile and will jump onto places Clover can't reach. Also, Clover hasn't ever shown aggression around me outside of the few times she's snapped at Snowbird to make her go away and as I said she was in a foster home with cats without any issues. (I feel like the reason this is different is that there was more going on in her foster home. It was a couple with a young baby and they had multiple dogs and two cats of their own; here it's just me, Clover, and Snowbird so that's a very different dynamic.) Any advice would be appreciated. Thank you!