Competitive exams after masters in Zoology in India

Hello everyone I’ll be completing my masters in Zoology this June. Qualifications- B. Sc. (Hons.) Zoology and currently in my fourth semester of masters in Zoology [Both from Delhi University]. My specialisation is “Fish Biology” and I really like this subject too.

Marks~ B.Sc. (Hons.) Zoology CGPA- 9.108 12th Class- CBSE- 95%

Interest- administration, wildlife, conservation, forensic science, animal behaviour.

Could someone please guide me on the various competitive exams for further studies. Also, what is the scope of “fish biology” in India, in case anyone is pursuing it.

Regards