Sprinklers normally work if a cat doesn't like water but if they do, try to get a sensor that detects movement and releases an alarm that should scare of the cat. Apparently their are alarms that only cat can only hear. I may be wrong but that is my suggestion.
There are sprays available at any pet store that you can use in your yard to discourage cats from wandering in your yard.
We use rubber snakes. Put them in yard. On cars. Or fences
A stray cat may be meowing at you for various reasons, such as seeking food, attention, or shelter. Cats use meowing as a way to communicate their needs and desires to humans.
stray dogs and cats :( if you mean method, then they usually use lethal injections
marbles
If he has kittens of his own he should not be hissing at all at them. Just get the kittens to leave the male alone. Always stay in the room when they are together and dont let them to close together. Sometimes you should try making the male feel so special. I have a female cat and she doesnt hiss at any cats exept for if they are in my garden or house. He is just defending his home he will get used to it.
Use a Dogpile.com search and they have high dollar static electric mats , or if the cats really tick you off, sneak up on it and whack that cat hard off the car, or if it is a hard top and you are not in a garage, throw a bucket of water from high up on it
You should not use Clorox or any type of bleach to keep cats away. Clorox and bleach are poisonous and can kill the cats.
Use bicycle clips.
ammonia does work to ward of cats, keep in mind it is a poisonous chemical and use it wisely. also some better approaches to warding off unwanted felines is sprinklers... or water hoses. if your there when your sneaky visitors arrive, spray them with water, this will more than likely reinforce to them that its not a pleasant place for them to be, and that they are unwanted there.
The leftover military explosives were put to good use demolishing burned-out buildings. The town's stray cats were taken to the warehouses and put to good use catching rats.
The ultrasonic cat repeller effectively deterred cats from my yard, reducing unwanted visits and mess. It was easy to set up and use, and I appreciated its non-harmful approach to keeping cats away. Overall, I would recommend it for those looking to keep cats out of their outdoor spaces.