The giant pandas Ying Ying and Le Le at Hong Kong's Ocean Park have moved a step closer to having their offspring finally after successfully mating for the first time on Monday.

After repeated failures and a miscarriage in the past 10 years, the black-and-white heartthrobs made it at the age of 14 during the ongoing mating season between March and May, the park said.

Their behavior is seen as a breakthrough as male and female giant pandas become sexually mature at the age of 7 and 5 years respectively.

Signs of pregnancy, if any, are expected to be observed at the earliest in late June.

"Since Ying Ying and Le Le's arrival in Hong Kong in 2007 and attempts at natural mating since 2010, they unfortunately have yet to succeed until this year despite years of trial and learning," Michael Boos, executive director of the park's zoological operations and conservation, said.

"The successful natural mating process today is an extremely exciting news for all of us, as the chance of pregnancy via natural mating is higher than by artificial insemination."

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In 2015, Ying Ying and Le Le joined a national program in Wolong, Sichuan, the biggest panda reserve in Mainland China, at which Ying Ying was mated with different pandas and also artificially while Le Le's semen was used to artificially inseminate other pandas.

Ying Ying was soon confirmed pregnant, but then miscarried. Several rounds of false alarms took place in the following years.

Boos said the park would closely monitor Ying Ying's hormonal levels and behavioral changes as the gestation period for giant pandas ranges between 72 and 324 days. Pregnancy could only be confirmed through an ultrasound scan 14 to 17 days before birth at the earliest.

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The debt-ridden Ocean Park has been closed for the public since January 26 to minimize the risks of the spread of the coronavirus.

"If the mating was successful, signs of pregnancy, including hormonal fluctuations and behavioral changes may be observed as early as late June. But there is always a chance Ying Ying could experience a pseudopregnancy," Boos said.

Tourism lawmaker Yiu Si-wing welcomed "the good news" of the successful mating.

"It gives us some hope when Hong Kong is clouded with so much negative news," he said.

The park has tightened its belt, and is in the process of seeking a HK$10.6 billion (US$1.36 billion) funding from the government for a makeover.

It is facing a cash crunch as it revealed in January that it only had about HK$400 million at hand at that time, sufficient for operations until the end of this year. The park is also burdened with about HK$6 billion in debts.

Yiu urged the park to revise its funding plan as tourism was battered by the COVID-19 pandemic.

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