I would strongly recommend doing some informational interviewing of people who are doing the jobs that you think that you might want to do to see if you really do want to do the
I add to this opinion. I would strongly advise against investing money or time in a degree before really knowing the field.
By all means get in contact with zoologists and ask them about their job and how you can help. Field research of animals is physically tough, assignments are temporary, no job security, lots of non-animal work like writing grants and money proposals, poor pay, often supplementing one's income with other job, personal problems due to girlfriend/spouse/child being 'left behind' during field trips. And you need a 'thing': field skills and experience with animals and nature, combined with a passion which turns physically tough and miserable activity into enjoyment. Most people don't have that.
I suggest the best path is:
- contacting local researchers who do things you want to do, get information and personal contacts;
- ask for a position of volunteer or field assistant in field research. Most are filled informally, and some are also advertised online. They are paid poorly, down to you financing personally half of it. They usually don't require a degree, but give you idea of the work, useful experience and more personal contacts. This is generally small field, and people know each other.
Somebody mentioned Earthwatch. I met them in the field. They seemed to be totally lost laymen who pay good money for a strange holiday trip. They don't get any useful field skills, contacts or any real help if you would want to become a zoologist.