An Invercargill farmer was startled when he went to his paddocks on Monday morning and found not baby lambs but a baby seal pup wandering the field.

When Dee Knapp first saw the little animal, he thought it was a bird with a broken wing.

"I thought wow, mate, you are lost!" he told Newshub.

"I've never come across it before… Never has there been a seal in the middle of nowhere."

There was no mum to be seen and with the sea around 10km away, Mr Knapp says the pup must have been travelling for days.

He called the Department of Conservation who advised him to leave it to find its own way back.

"When I saw him, my cow was stomping around him and just being a little bit overexcited. If I left him out there, he would've been trampled," he said.

"I couldn't leave him there. I knew I gotta do the right thing."

Instead Mr Knapp did some research and picked him up in a blanket, taking him home and feeding some fish. Once the pup rested a bit, he was taken and released back in the water.

Afterwards, Mr Knapp says DoC called him back and was understanding about it all - but warned he could have faced a $250,000 fine for touching the seal. But his heart was in the right place.

"I knew he wouldn't have survived. There's dogs and all sorts of animals - and he's just a baby. He didn't have a mum to protect him. It didn't feel right," Mr Knapp said.

"I'm just doing what any normal person would do. You don't leave something defenceless like that on its own and let it fend for itself - it's not right.

"It was distressed because it was in the middle of nowhere and my paddock is right next to the main road."

Mr Knapp's advice to any other aspiring seal rescuers is to do some research and contact DoC in the first instance.

"Let them know what's going on and then if it's in danger, let them know it's in danger," he said.

"Don't get everybody in and onto it because [fur seals] tame up quite easy. If you feed them... it could end up putting them in danger."

New Zealand fur seals are a protected species, after once being hunted to near extinction. Its protection status has since seen its population rise back up again, and it continues to grow.

Newshub.