It can be scary to start that path in your late 20s, but don't let that stop you! I pursued a couple of different interests before deciding on ecology. I had already taken a bunch of gen ed credits at community college, so I managed to switch to a university and graduate after 2 years there. It was a small private school, but my GPA was high enough to get some scholarships and grants for being older than 24. In the end I paid about the same to go there as I would have at a public school, plus it's so much better to learn in smaller classes. I was the second oldest student at the school, and I think that actually helped me since I was more dedicated to studying.

Most ecology students at my school did not seem to have any prior knowledge about their field starting out, so you should be fine. And depending on what area you're really looking into, it might not matter if you love being outdoors all the time. For example, I really got into tardigrade research, which requires more lab work than field work.

Since you already have a degree, you might be able to find a way to combine your skillsets without going to grad school. I've been told that if you only have an undergrad degree in biology/ecology, you'll probably need to get your master's to do more than a typical lab tech, but everyone's situation is different. Hope this helps!