In the past, the airline has required a doctor's note from passengers who wish to bring an emotional support animal on board the aircraft with them.
But after a series of bizarre, and sometimes dangerous, incidents with animals in the cabin, passengers with an emotional support animal will need to bring proof of the animal's health and a signed document assuring the airline the animal is trained and aggressive.
"Customers have attempted to fly with comfort turkeys, gliding possums known as sugar gliders, snakes, spiders and more," Delta said in a statement posted on its website. "Ignoring the true intent of existing rules governing the transport of service and support animals can be a disservice to customers who have real and documented needs."
The move comes less than a year after a man was severely injured on a Delta Air Lines flight after officials say he was attacked by another passenger's emotional support dog just prior to takeoff.
“The rise in serious incidents involving animals in flight leads us to believe that the lack of regulation in both health and training screening for these animals is creating unsafe conditions across U.S. air travel,” said John Laughter, Delta’s Senior Vice President — Corporate Safety, Security and Compliance.
The airline requires a veterinary health form to be submitted for trained service animals, which assist people with disabilities.
In addition to today's announcement on additional documentation, the Atlanta-based airline has created a dedicated Service Animal Support Desk to assist customers traveling with service and support animals.
Delta has seen an 84 percent increase in reported animal incidents since 2016, including urination, defecation and biting, according to a press release.