Found that rhino is seen regularly in part of North America (7)
I believe the answer is:
ontario
'part of north america' is the definition.
('Ontario' is part of 'north america')
'found that rhino is seen regularly' is the wordplay.
'is seen regularly' means one should take alternating letters.
'found'+'that'+'rhino'='foundthatrhino'
The alternate letters of 'foundthatrhino' are 'ONTARIO'.
'in' acts as a link.
(Other definitions for ontario that I've seen before include "Province of SE Canada, and a Great Lake" , "Province of central Canada" , "Most populous Canadian province" , "vast lake" , "part of Canada" .)