To ask you a question about job hunting

[Kazziepooes]

I'm currently looking for a new job in the same industry; however I have become nervous that if any of my current colleagues / bosses find out that they might phone my potential future employer to warn them off me out of spite. Is this actually possible?

depends upon what industry, but if they want you to leave it would be in their interest to give a glowing reference ;) Totally unethical if they were to do that!