We've got 4 cats and all of them are spayed/neutered.

Katie is 9, Jack is 5 and Sally is 15 months. Before Sally we had Saffy who was 14 when we lost her, they all got on OK together without problem.

Then we got Amy who is now 5 months old. They do all get on but Jack is pouncing on Amy and making her cry. It looks as if he is trying to mount her but he has never done this with the other girls, and why start now? She's only just been spayed herself and can do without this. He jumps on her back, pins her down, yowls and bites her and it makes her cry. Other than shout at him and lob cushions I don't know what we can do.

Anyone come across it and any suggestions? It could just be male dominance as he feels threatened by 3 girl cats? I don't think he is trying to have sex with her because I don't think he has a clue what to do! He was neutered at 4 months.

He's probably just putting her in her place and will continue to do so till she gets it and realises he's in charge.

Yes she is a bit feisty! She's a calico and they have I think a reputation for being a bit stroppy!

I had a similar experience to this.
Have a 5 year old neutered ginger male cat that I got from the RSPCA nearly three years ago.

About a year ago I tried to adopt a 6 month old female cat from another shelter.
Unfortunately my ginger cat wouldnt have it. He jumped on her, turned on her and held his paw up as if he was going to hit her, and after a long weekend of this I had to take her back to the shelter.
He was so territorial and bullying I just couldnt put her through it any longer.
Its sad, but I know now that my cat doesnt like other cats and wont have them in the house.

Thats exactly what cats do when they mate, it can be a bit violent. As she's only just been spayed it's possible she still has the hormones flowing through her and thats what he's reacting to. He's simply acting on instinct. Just because he's been spayed doen'st mean he can't have the urges! Hopefully when the hormones are all out of her system things will quieten down.