Career in astrophysics or ethologist and money problem?

Neither pay very well considering how long you'll spend in school for it (more like 60-70k average for astrophysics at least). They aren't seen as very useful at the moment, and there's no real industry to drive up salaries in those fields. Most are paid on grants anyway, and those aren't easy to get and come in many sizes. Don't bother with it unless you can't see yourself doing anything else.