You mean hobbies that were put aside to complete and manage a pond system..:-))
I have my own wildlife refuge I spend a lot of time on, I fly Large scale RC helicopters professionally, I fish walleye tourneys semi-professionally, I'm a full-scale pilot and spend some time practicing aerobatics.. I do seem to have a bit of a green thumb-I think obtained from my mother-and I enjoy growing different trees (or the challenge of) growing trees from seed.
I consider my job working with fisheries as an actual job but in reality, it's a love for that that keeps me involved so technically, more of a hobby.