The 2003 bushfire was the second blaze in just over a year to burn many hectares of pine trees around the National Zoo and Aquarium, but there was a silver lining - it paved the way for a major expansion that has tripled the size of the site and will soon reach its next milestone.

Natural disasters, bankruptcy, a near-collapsed aquarium and lack of experience were some struggles the Tindale family faced in transforming the basic and rundown site into a buzzing tourist attraction.

The first dilemma immediately followed Mr Tindale's bold decision to sell his building business and buy the Yarralumla site in 1998.

"We had all the passion in the world for animals, but we were empty in experience," he said.

"It took quite a while to build up the credibility with the community and convince them we were there for the right reasons."

The desire to help endangered animals had simmered in his mind for some years, but when he visited Dreamworld's Tiger Island that dream became a realistic goal.

It was there he met Bakkar the Bengal tiger. Bakkar later spent 12 years at the Canberra zoo before dying of kidney failure.

"I left knowing I wanted to do something for animals, with animals."

He sold his business and set off on an around-the-world adventure to learn about big cats with his wife, Maureen.

"We travelled as far as South America to North America, to Canada and Alaska, Nepal, Siberia, India and a number of African areas," he said.

"We came to the conclusion there weren't many big cats left in the wild and if things kept going the way they were ... the species would get wiped out."

Of the world's 40 wild cat species, about 80 per cent of them have populations in decline, according to National Geographic.

On returning home the couple saw the sale of the Canberra Aquarium as the perfect opportunity to do more than breed cats - they could potentially help save dozens of species on the brink of extinction.

It was obviously not an easy mission to embark on, given the facility was limited to a handful of native animals and had gone bankrupt twice.

"It needed a lot of work, there was very little down there," Mr Tindale said.

"The aquarium had no reptiles along the wall and it mainly relied on day trippers from Sydney."

There was the added stress of limited experience and pricey renovations. Mr Tindale wouldn't divulge the pricetag, but admitted he put everything he had into the site.

After doing extensive research into the complicated zoo industry, hiring several skilled staff and making some personal sacrifices, the visitors eventually started flooding in.

But the family faced another setback when they tried to fill the main aquarium with salt water to add more animals and the concrete almost crumbled entirely. They rebuilt another shark tank and the empty one became a feature of the Jamala Wildlife Lodge, built in 2013.

Mr Tindale credits the zoo's financial survival to Jamala, where guests sleep in private bungalows amidst animal enclosures. They transformed their own home into the accommodation and rebuilt their house at the back of the zoo.

In December 2001, the first bushfire threatened all they worked for. It burned all surrounding pine trees and crossed all four boundaries of the zoo, with up to 50 spot fires igniting inside the site.

"We were maybe a little complacent about it because we thought there was no way the fires could get to us," he said.

"But it was so strong. It was just jumping down that arboretum site, jumping 100 metres and then 200 metres along the grass and we started to panic."

"The fireballs landed inside the zoo and started igniting things, including the shearing shed."

"It was also very awkward for us, because it is great to have a contingency plan but you can't evacuate 25 big cats and four giraffes. That could take months."

Fortunately, the lack of flammable vegetation meant the zoo escaped without major damage.

The 2001 bushfires were a larger threat to the zoo than those in January 2003, which gutted nearby suburbs but just missed the zoo.

The ACT government's move to cut all the trees surrounding the site opened the door for Mr Tindale to obtain 18 hectares and begin the almost-finished expansion. He was offered 60 hectares but lacked enough water resources.

The whole process of transforming the zoo and building credibility within the industry was one of "organised chaos".

"Though some would say disorganised," Mr Tindale said.

But he felt a sense of accomplishment as he reminisced on the challenging yet rewarding journey.

Given his love of big cats, it is not a surprise the zoo boasts Australia's largest collection. It also houses Australasia's only tigon - a hybrid cross between a male tiger and a female lion.

Staff numbers have increased about six-fold in the past decade and the number of endangered species taking part in breeding programs continues to grow. Mr Tindale said the open exhibits of the expansion would allow for the breeding of more large animals than previously possible.

Mr Tindale acknowledged that managing the zoo had become the family's life but he said he'd gained considerably more than he'd sacrificed.

"I'd like to say I've given up everything, but I haven't," he said.

"The number of people who visit and get so emotional when they talk to you is unbelievable, who came here for adrenaline rush and walk away with a different view."

"It's that long-term goal of the the more people who see something special, the more impact it will have on the animal kingdom. That is what motivates us, it is what we've dedicated our lives to."

To celebrate the expansion of Canberra's National Zoo and Aquarium, a series of animal portraits by Canberra Times photographer Rohan Thomson has been made exclusively available from The Store by Fairfax. The prints are available in three sizes and priced from $90 including GST. Ten dollars from the sale of each print will go to conservation charities selected by the zoo. To own a copy of one of these beautiful animal portraits, visit thestore.com.au/zoo