In the shade, out of the Washington Easter Sunday afternoon sunshine, 24-year-old Tian Tian and 23-year-old Mei Xiang sit eating side by side, sometimes tussling over a large bamboo stick.
Nearby 19-month-old Xiao Qi Ji is sleeping, oblivious to all the fuss.
Tian Tian and Mei Xiang are giant pandas.
The giant pandas have been one of the main attractions at the Smithsonian’s Washington National Zoo for years. Millions across America have been fascinated by their lives, rejoicing at the birth of their cubs, mourning at their deaths and watching in sorrow as some departed.
Over recent days, however, the black and white bears have been even more the centre of attention.
Over Easter Sunday morning the pandas had visitors from the top brass of the zoo as well as from the Chinese ambassador to the US. They also were given special ice cakes with bases made from frozen diluted apple and pineapple juice, decorated with sweet potato, apple, carrot, pear, sugar cane, banana and yellow groove bamboo.
The celebrations centred not around Tian Tian and Mei Xiang directly but rather took place to mark the 50th anniversary of the arrival of an earlier couple of giant pandas as a gift from the Chinese government.
The arrival of the bears – Ling-Ling, a female and the male Hsing-Hsing – in Washington came several weeks after the shock visit of the then president Richard Nixon to Beijing in February 1972.
It is probably hard now for many people to realise how stunned Americans were 50 years ago to hear that Nixon was going to China. Nixon was an anti-communist hawk while the Chinese leader Mao Zedong was the champion of global revolution.
No American president had ever been to China and the US did not recognise the communist government in Beijing. There were very limited diplomatic contacts and few business links.
But Nixon and his secretary of state Henry Kissinger had secretly plotted an approach to China and the White House planned an eight-day extravaganza around the visit designed to maximise exposure on television back home.
The meeting between Nixon and Mao suited both at the time.
Domestic troubles
The US was still embroiled in the war in Vietnam which had cost more than 50,000 American lives while Nixon was also facing serious domestic troubles. America wanted China's help to extricate itself from the quagmire in southeast Asia.
The Chinese, for their part, had been isolated for decades and had fought a border conflict with the Soviet Union in 1969.
The story goes that Nixon's wife, Pat, had seen pictures of pandas on a box during one of the banquets organised during the visit and that the Chinese premier Zhou Enlai had, on the spot, offered first lady Pat Nixon a gift of two bears.
These were the pandas that subsequently arrived in Washington several weeks later with 20,000 people turning up to see their first public appearance.
There were attempts to breed the pair. Ling-Ling did have several cubs, including a set of twins but all were either stillborn or died soon after birth.
Ling-Ling died in 1992 and Hsing-Hsing seven years later.
The Washington zoo did secure other pandas. However, unlike Ling-Ling and Hsing-Hsing, who were gifts from the Chinese government, the subsequent bears came essentially as part of a commercial arrangement.
Tian Tian and Mei Xiang arrived in 2000, initially on a 10-year, $10 million lease.
The International Space Station shows that co-operation in niche areas can survive even in fraught political times
On this occasion the breeding programme was successful and in 2005 the first cub, Tai Shan, arrived.
There have now been three others. The first three have already been sent back to China when they reached four years of age as part of the lease arrangements. Some now have their own cubs.
Tian Tian and Mei Xiang are scheduled to return to China next year as will Xiao Qi Ji, likely to be their final cub given their ages.
The zoo is hopeful that a new agreement can be reached so the panda habitat of trees, rocks and streams does not lie empty for long.
However, political relations between Washington and China are very different in 2022 to how they were when the Nixons arrived in Beijing in 1972.
The ongoing links between the Americans and Russia over the International Space Station show that co-operation in niche areas can survive even in fraught political times.
There are benefits to both sides from the panda programme – in terms of both breeding accomplishments and public recognition and support for the species. It remains to be seen, however, whether there will be black and white bears on show to receive ice cakes on the 60th anniversary.