Vaccinators wear protective masks as they get their temperature checked, during an anti-polio campaign, in a low-income neighborhood as the spread of the coronavirus disease (COVID-19) continues, in Karachi, Pakistan on July 20, 2020. (Photo by Akhtar Soomro/Reuters)

A health worker gives a polio vaccine to a girl on a street in Lahore, Pakistan, Monday, June 27, 2022. Pakistan launched a new anti-polio drive on Monday, with the goal to vaccinate a million children across Pakistan. (Photo by K.M. Chaudary/AP Photo)

A barber cuts hair of his client at a shuttered market during the countrywide traders strike in Lahore on October 29, 2019. Pakistani traders have joined hands to observe a nationwide shutterdown strike against the government over its “anti-business” policies, seeking to bring trade and economic activities across the country to a standstill on October 29 and 30. (Photo by Arif Ali/AFP Photo)

A man reacts while having a nasal swab sample taken at a testing and screening facility for the coronavirus, in a hospital in Karachi, Pakistan, Friday, August 21, 2020. (Photo by Fareed Khan/AP Photo)

The front wheels of a tractor lift off the ground as the driver moves a heavy trailer outside Peshawar, Pakistan February 19, 2018. (Photo by Fayaz Aziz/Reuters)

A man plays with his pet goat while taking a bath to cool off in a canal during hot and humid weather in Lahore, Pakistan May 30, 2018. (Photo by Mohsin Raza/Reuters)

Elephants cool off at a zoo in Karachi, Pakistan, 31 March 2021. Caretakers at Karachi's zoo were working to keep animals cool during a heatwave affecting southern Pakistan. (Photo by Shahzaib Akber/EPA/EFE)

An unexpected side-effect of the flooding in parts of Pakistan has been that millions of spiders climbed up into the trees to escape the rising flood waters. Because of the scale of the flooding and the fact that the water has taken so long to recede, many trees have become cocooned in spiders’ webs.