Here are some hints from someone who deals with LOTS OF CATS WHO ARE SCARED. And who used to deal with dog rescue.

From someone who works in cat rescue, ANYTHING can be a litter box.

Yes they do have fancy travel litter boxes with a zipper that closes (air plane safe - mostly) but I just end up using a dish pan from the Dollar Tree. I stack several together with a bunch of quart bags full of compressed pine litter. 1 bag fills one pan. Yes, that is all that is needed. Compressed pine can be dumped just about anywhere and is environmentally friendly. So it can be dumped at the sides of the roads. It is also great for smells and dries out the turds.

They have collapsible soft sided kennels that collapse flat. The larger ones will fill the entire backseat of a standard car and they even have seat belt loops. They can be twisted and folded into a small circle and stored flat.

But the easiest thing to have for cats are soft carry bags. Think of a sling bag that has a hole in it for the cat's head. Several cats can be carried by one person this way with each cat being in its own carry bag. The material these are made from is a heavy duck like material that is mostly waterproof. Their claws can't penetrate it for the most part. After the bags get older, yeah, but keep your cats claws trimmed properly anyway. These can also be used with seat belts to safely contain the cat in a seat.

You can carry dogs in the sling bags but they aren't normally made very large.

They do have backpacks for pets and are more common for dogs but I have better luck with baby carriers for the smaller dogs. My MinPin just doesn't fit a dog backpack but fits into a human baby carrier.

Have puppy pads with you to put under the kennels and litter pans. A scared cat can't always make the litter pan. They might get close but fail to hit the mark. Also, put puppy pads over the seat where you have the cat strapped in. Because you can't get mad simply because they are scared.

The reusable puppy pads are easy to wash but will take several days to dry without being spun dry unless they are in a very dry environment. Most cannot go in a conventional hot dryer, only one kind that I know of is completely dryer safe. But the reusable puppy pads are more comfortable for cats to lay on and use and puppies are really easy to train to use puppy pads. So if you have both cats and dogs in a household like I do, with the litter pan on the puppy pad the cat uses the litter and the dog uses the puppy pad. And if the cat misses, there still isn't a mess.

With your pet supplies, keep a small amount of laundry detergent good for cleaning pet smells. Something like Foca which is enzymatic and breaks down protein smells. Where you wind up is you bug out might not have anything safe for pets or anything made to handle pet smells, so plan ahead. And baking soda also helps with smells

It is best to carry your pet food with you. A nervous pet will want what is familiar and may refuse to eat a new food in a new environment. This happens often in rescue situations. We try to identify what they have been eating. Cats have been known to starve when food is RIGHT THERE because they don't realize it is safe.

Now, smoke issues.

Cats won't eat what they can't smell. Cats can starve to death if they get a sinus infection and usually have to be force fed and forcefully hydrated or given IVs. Dogs don't generally have this issue, they will often become poisoned eating things when hungry that isn't safe. Usually it is best to give cats a few days waiting to eat food AS LONG AS THEY ARE DRINKING. If they are also not drinking, have a syringe or an eye dropper and be prepared to force water if needed. So have an old syringe (no needle) and eye dropper in your medical kit marked FOR CATS.

Don't ever give cats milk instead of water. Regular milk will give them diarrhea as all cats are lactose intolerant. So you think you are helping but you can make them even more dehydrated. And don't give them "milk" derived from nuts as many of those nuts aren't cat safe.

Unless you have taken your pet on drives and gotten them used to family car trips, not having them restrained in some way IS NOT SAFE. Jumping out windows is common in cats and jumping out of the first open door is common in both dogs and cats. So always have harnesses, collars and leashes available-- even if they are in a kennel. Because if the door fails or you are in an unsafe place when you try to move them, they can bolt. So what I do is have quart and gallon ziplock bags with extra harnesses, collars and leashes organized by size and with pet names listed that they fit. They stay stored in with the collapsible kennels when not needed.

If your pet gets dirty ---and in the recent fires, you will have both smoke, fire debris and dangerous chemicals on many pets, they need cleaned. If you can't find any or you don't have a pet safe shampoo, use Dawn dish liquid. Don't use any conditioner under normal circumstances. If they have sores, you can use PURE coconut oil to soothe raw places and it can also help cats with hair balls. Again many nut based oils are toxic to cats so read those labels carefully. If you have an upset cat, smooshing solid coconut oil in their fur will usually cause them to start bathing and it will lead to self-soothing and will often calm an upset cat.

Dogs all have different soothing behaviors that are usually connected to humans, beit belly rubs, playing fetch or chewing on their favorite toy. So with dogs, it might mean having a backup dog chew or toy in your preps.

It is usually best to pack the pet's personal bed unless space is an issue. Then it might just be a towel or blanket that smells familiar. If nothing else, give them your dirty shirt or underwear so they get that familiar smell. This is more effective with dogs than cats but cats have been known to carry around underwear to make a new bed in a corner. And beware of using perfume or heavily perfumed deodorant when giving clothing to pets, not all fragrances are pet safe.

Dry pet food only keeps for a few months. The oils can go rancid and it is prone to pantry moth infestation. Canned food can last a very long time but this must also be rotated and be a food the animal is familiar with- sudden changes isn't good. Plan for at least 5 days of dry food and 5 days of wet food PER PET when bugging out with a pet.