Last month, a sad-eyed husky named Mickey arrived from Iraq. He belongs to an Army sergeant who found him underfed and cut by barbed wire on the mean streets of Makhmour. The sergeant, who was adopting Mickey through a program for service members called Operation Baghdad Pups, was sending the dog ahead to his family in Texas. But airlines will not fly animals to any place where the temperature is expected to get above 85 degrees, so Mickey would end up cooling his heels at the Ark for nearly a week.

“He’s very needy, so I’ve been taking him into the office with me,” said Elizabeth A. Schuette, the Ark’s managing director. “One day he chewed on a corner of my cubicle.”

The racing pigeons, headed to Zimbabwe to compete in the $200,000 Victoria Falls World Challenge, got booted from one flight in June because the plane had to take on extra fuel to fly around a storm, and another because the passenger load was too heavy. They stayed in their shipping crates in the Ark’s Avian In-Transit Quarantine wing.

The air shipment of live animals is subject to a vast array of rules and regulations. Under federal law, for instance, “Live guinea pigs and hamsters shall not be transported with any material, substance (e.g., dry ice) or device which may reasonably be expected to be injurious to the health and well-being of the guinea pigs and hamsters unless proper precaution is taken to prevent such injury.” On top of this, airlines impose their own restrictions. On KLM, “The transportation of horses transversely to the flight direction is not permitted. Horses must travel facing forwards or backwards.”