Google has used its search engine homepage to pay tribute to Steve Irwin on what would have been the conservationist and television star's 57th birthday.

Key points: Internet searches for Steve Irwin surge as Google pay tribute to the conservationist

Internet searches for Steve Irwin surge as Google pay tribute to the conservationist Terri Irwin says the The Crocodile Hunter series was inspired by their honeymoon

Terri Irwin says the The Crocodile Hunter series was inspired by their honeymoon Terri says the family will continue Irwin's life work

The Google logo was on Friday replaced by an illustration of the Australian holding a crocodile, the first in a series depicting Irwin's adventures as an animal rights activist, showman and family man.

Google users around the world saw the illustrations, which led to a large spike in internet searches for the Crocodile Hunter star.

In a blog accompanying the tribute, Irwin's wife Terri Irwin recalled how the pair's less-than-traditional honeymoon inspired the television series that would make him an international name.

They were married in Oregon in the United States in 1992, but had no plans to settle down.

"We received a phone call about a poacher trying to kill a large crocodile in North Queensland, so instead of a honeymoon, Steve and I went to Australia to save the croc before the bad guys got him," Terri wrote.

"We invited a film crew to come along and document our efforts.

"We didn't know it at the time, but this would turn out to be the very first episode of The Crocodile Hunter and the beginning of a 14-year adventure, filming in locations across Australia and around the world."

A love story … with crocs

Steve and Terri Irwin went on a crocodile rescue mission for their honeymoon. ( Google )

The pair's romance began in Beerwah, Queensland, at the Irwin family's reptile park, which would eventually become Australia Zoo.

It was 1991 and Terri was Terri Raines, a naturalist holidaying in Australia with friends who stopped in at the park to watch a live feeding demonstration.

As she watched, she was struck by the "outspoken man" in khaki who had a clear passion for crocodiles.

"He was actually inside one of the croc enclosures sharing with the visitors just how special crocodiles really are," Terri said.

"I had never heard anyone speak about crocs with such enthusiasm, much less have the calm courage to hand feed one of these giant saurians.

"I just had to speak to him. It was a decision that would change my life forever."

An illustrated history

The Google doodle documents the stages of Irwin's life, starting off with his youth catching and relocating crocodiles for the Queensland government.

He spent months at a time hunting crocodiles in remote areas of Far North Queensland with his small dog Sui for company.

Irwin wanted to encourage conservation though "exciting education". ( Google )

He took control of the wildlife park in 1991, renaming it Australia Zoo in 1998.

His motto was "conservation through exciting education", with the zoo famous for its live demonstrations.

The animation pays homage to Irwin's showmanship in the croc enclosure and charisma in front of the camera, but it is the depiction of him with a young Bindi and baby Robert that pulls at the heartstrings.

"The very best part of our lives together would have to be our two incredible children," Terri wrote.

Steve and Terri Irwin's children, Bindi and Robert, inherited their parents' love of animals. ( Google )

Conservation work carried on

Irwin died on September 4, 2006, after being stung through the heart by a stingray while diving on the Great Barrier Reef near Port Douglas.

"Losing Steve was a real crossroads for us, but together we decided to continue his mission," Terri wrote.

"Bindi, Robert and I have dedicated our lives to the wildlife conservation work that Steve began."

That sentiment is reflected in the final slide in the animation, which depicts Terri with Robert and Bindi as young adults, with their father watching on from an Australia Zoo billboard.

Loading

"Today we continue his mission by working to overturn recent legislation in Queensland which allows crocodile egg harvesting from vulnerable crocs in the wild to support the commercial leather trade," Terri wrote.

"Steve's legacy will definitely live on."

The final illustration in the series depicts the Irwin family carrying on Steve's conservation work. ( Google )

Honouring a legend

Global marketing lead for Google Doodles Perla Campos told the ABC the prospect of paying tribute to a personality like Irwin's seemed difficult at first.

Ms Campos, like many people around the globe, was inspired by the Crocodile Hunter.

She and her siblings would mimic Irwin's adventures in their backyard, however, they would handle salamanders and frogs instead of crocs.

"I loved catching his show when I was growing up," she said.

"I used to be so scared for him when he'd get up and close with a toothy critter, but his fearlessness and admiration for animals helped me shed that, and impressed on me the importance of wildlife conservation."

Loading

So just how do you convey this infectious energy through an illustration?

"The creation of the art was the product of close collaboration between the artist, our local Australian Googlers, and the Irwin family," Ms Campos said.

"Our goal was not only to pay homage to Steve, but also create something authentic in the eyes of those who loved him.

"After reading his writings online, and watching footage from his documentaries and interviews — the time he was on Oprah is particularly memorable — it seemed the best way to honour him in a Doodle would be to capture how genuine he was in his life, on screen and off.

"He honestly loved crocs, nature, his family, and teaching the world about wildlife in an exciting way, which is why I think people have always been drawn to him.

"If I could communicate even a fraction of this in the imagery, then I think the Doodle was successful."