How to trap a feral cat

My post:
The "benefits" to a feral cat of being re-abandoned are dubious at best. Their accumulative effect on our native wildlife is devastating! The practice should be outlawed... Hey, wait a minute, it is against the law to abandon pets in most if not all of the United States, and it is against Federal law to endanger migratory wildlife. So the practice of TNR is against the law, the laws aren't being enforced!