Sometimes, yes! In most cases people are not intentionally breaking the law. That’s not an excuse, but if it’s safe to do so having a polite conversation that mentions the risk to birds’ nests/eggs, and the laws protecting nests/eggs, may well be enough to stop any action which would cause harm and suffering and break the law. If that doesn’t work or it’s unsafe to get involved and there is an active nest at risk hand the matter over to the police. We can also contact RSPB Wildlife Enquiries on 01767 693690. They will always try to help but have no enforcement powers and will refer the matter to the police for investigation if they think a prosecution is warranted.