It was the last day to see the giant pandas at the Toronto Zoo before the beloved bears headed off to Calgary on Sunday.

The pair of pandas - Da Mao and Er Shun - arrived at the zoo on loan from China in 2013 as part of a global giant panda conservation breeding program. Their cubs - Jia Panpan and Jia Yueyue - were the first giant pandas born in Canada.

Thousands of visitors lined up at the Giant Panda Experience pavilion to bid farewell to the ever-so-cuddly black-and-white bears.

"It has been a crazy five years since they came here, although it was a little bit stressful," said Maria Franke, the zoo's curator of mammals. "I will definitely miss the pandas. They have won everyone's heart."

"I am sad that pandas are leaving, I will always remember them," a young girl named Emily said with tears reddening her eyes. "I will visit them again if they can come back."

"This is the better zoo, stay here, please don't take them away. You're individuals; you have rights, stay here!" Emily's brother chimed in.

"You know besides it being a lot of fun, it has been very educational for people who live in Ontario," said Amanda, another visitor. "We're excited for Calgary to have the chance to see them, but we really will miss them."

Since the pandas arrived in 2013, more than 1.4 million people have come to the zoo to see elders Er Shun and Da Mao. It was the zoo's third highest attendance since its opening in 1974, and its highest revenue year to date.

The furry creatures also have generated plenty of chatter. As part of the loan deal with China, the zoo agreed to pay $1 million annually to the Giant Panda Conservation Fund. Although it's expensive to feed giant pandas, Councillor Paul Ainslie, chair of the zoo's board of managers, told media that he "doesn't regret the pandas coming to the zoo".

"It is worthy for us as humans to help preserve this species," said visitor Wayne. "For sure it's worth a million dollars a year to do that."

Former prime minister Stephen Harper, who greeted the bears at the airport five years ago, said the giant pandas' presence "reminds us of the strong relationship between the two countries".

Prime Minister Justin Trudeau also came to cuddle with the cubs on their first birthday and revealed their names of Jia Panpan and Jia Yueyue, meaning Canadian Hope and Canadian Joy respectively.

According to the zoo, the conservation breeding program has met with some success over the past five years, with the giant panda being downgraded in 2016 from an "endangered" species to a "vulnerable" one by the International Union for Conservation of Nature.

"That's the ultimate conservation goal for any biologist," said the zoo's Franke.

"We wish Da Mao, Er Shun, Jia Panpan and Jia Yueyue all the best on their new adventure in Calgary."

The four pandas will live at the Calgary Zoo until 2023 in "Panda Passage," a newly constructed habitat.