There are usually funded PhDs at most universities - try searching the Texas A and M natural resources job board (includes opportunities from all over the USA and sometimes internationally): https://jobs.rwfm.tamu.edu/

If you are looking for opportunities in the US, you can also look on the job boards for professional organizations like the Ecological Society of America or The Wildlife Society. If there are individual researchers you are interested in working with, you can also reach out directly with them with what types of research projects you are interested and any ideas for research projects that you have, in and ask if they have any funding. Many do and have not posted official job announcements about it yet. Best of luck!

thank you very much for the answer.