HAVANA, Sept. 23 -- Every day, veterinarians and zookeepers make their way to Cuba's National Zoo by whatever means they can, determined to not abandon the nearly 1,000 animals in their care and help save species at risk of extinction.

Their dedication and food donations are vital to keeping alive an array of rhinos, jaguars and tigers - including an extremely rare white tiger - in the midst of a severe crisis that has left many Cubans struggling to feed themselves.

Just getting to the reserve situated 20km from central Havana is a headache for staff, as public transportation has come to a near standstill nine months into a US fuel blockade.

"The workers come by bicycle, pedal scooter or electric motorbike to ensure the animals have fo...