Hi Martin and welcome to the Q&A Board!
Our feature article this month is on taking photos of birds with a digital camera. The author uses a few FZ cameras. I think you'll find it contains some of the information you're looking for.
http://www.digicamhelp.com/how-to-photograph-birds-with-digital-camera/index.htmI believe the FZ5 has a fast-focus mode, so make sure you turn it on when birding. If it has a panning image stabilization mode, you may want to try it for certain shots. I often prefocus when taking photos of birds.