Taken from a chicken site but will help those egg bound pigeons also. Just be sure to reduce the size of the container.
Just wanted to share a helpful tip. Have an egg bound hen….this is the best way we have come up with to help ours out. Warm water, cup of epsom salt and a 20q/19L tote with a cover. Cut a hole in the cover for your chickens head and let her soak for about 20 minutes. Helps save your back and helps lessen the stress for your chicken.