With footfall plummeting with the temperatures, the wolves, camels and white tigers of XII Misyatsiv Zoo in Demydiv that survived the Russian invasion would perish without improvised emergency generators to keep them warm.
The animals have been traumatised from shelling in the early days of the conflict after Russia invaded Ukraine on February 24.
It came amid claims desperate Russian soldiers were killing and eating exotic animals as starvation spread through their ranks.
Rescue workers arrived 10 days later to find animal skeletons and pieces of flesh and bone scattered across the zoo grounds.
“Many animals were eaten by the orcs,” a volunteer said, using the local slang for Russian soldiers.
According to the authorities, two camels, a kangaroo, a bison, piglets, birds and wolves were killed.
When Russian forces first invaded director of the zoo, Mykhailo Pinchuk, said: “We are freezing to death. The zoo is cut off.
“No one is allowing us to bring anything here, and they have no plans to fix anything.
“Our stores of diesel fuel are exhausted and we are starting to die.”
It came as four and a half million Ukrainians have been left without power following Russian attacks on its energy network and President Volodymyr Zelensky accused Putin of “energy terrorism”.
Mr Zelensky, in his nightly address, also said “the very fact that Russia is resorting to energy terrorism shows the weakness of our enemy”.
The attacks on Ukrainian power and water supplies come as winter approaches.
Temperatures can fall far below freezing in winter, now just weeks away.
“They cannot beat Ukraine on the battlefield, so they try to break our people this way,” Mr Zelenksy said. “Tonight, about 4.5 million consumers have been temporarily disconnected from energy consumption.”
For more information and to donate visit the zoo website.