The poacher, identified as Kastam Ali, was nabbed by patrolling forest guards, forest officials said.
A full-grown female rhino was killed by poachers on the night of December six near the Amulya forest camp of the Park, however, they were unable to take away its horns.
A massive search operation was launched in the area since then to nab the poachers which would still continue, sources added.
Two rhinos have been killed in the Park during the current year.