'Customers have attempted to fly with comfort turkeys, gliding possums known as sugar gliders, snakes, spiders and more,' the airline says. Picture: SIPPLIED
'Customers have attempted to fly with comfort turkeys, gliding possums known as sugar gliders, snakes, spiders and more,' the airline says. Picture: SIPPLIED

The day of the service duck and emotional support chicken on airlines may be drawing to a close.

Delta Air Lines says it will more thoroughly vet passengers’ efforts to fly with all manner of unusual animals, which often board US airlines under the guise of psychological or medical support.

"Customers have attempted to fly with comfort turkeys, gliding possums known as sugar gliders, snakes, spiders and more," the airline says.

"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."

From March 1, Delta customers travelling with a service or support animal must show proof of the animal’s health or vaccinations 48 hours before a flight. Besides a letter signed by a doctor or mental health worker, people with psychiatric service or emotional support animals must sign a form to attest that the animal can behave.

"The measures are intended to help ensure that those customers travelling with a trained service or support animal will no longer be at risk of untrained pets attacking their working animal," Delta says.

Delta flies about 700 service animals a day — a 150% increase since 2015. The Atlanta-based company says reported "animal incidents" have increased 84% since 2016, including on-board problems with urine, faeces and aggressive behaviour.

In June, an Alabama man was taken to an Atlanta hospital with facial wounds after a dog lunged at him on a Californian-bound Delta 737. A police report said the dog was issued to a US Marine for support.

The airline considers the matter a safety risk, Delta spokeswoman Ashton Morrow says. "There is a lack of regulation and what we’re trying to do is put some more arms around the process and ensure we’re keeping safety top of mind."

For several years, flight attendants have been calling attention to the probable abuse of rules allowing service dogs and emotional support animals in aircraft cabins. In many cases, the animals aren’t confined and may amble about the cabin, creating safety concerns.

The Association of Flight Attendants "adamantly supports" Delta’s policy change, president Sara Nelson says, as "it appears there is growing abuse of the system. We are hearing a public outcry to stop the abuse."

The 1986 Air Carrier Access Act requires airlines to transport disabled passengers’ service and support animals, but the department of transport allows carriers to require documentation from the animals’ owners. Even with the proper verification, airlines may refuse to fly the animal "if the service animal’s behaviour in a public setting is inappropriate or disruptive to other passengers or carrier personnel", the department of transport wrote in a 2005 guide for airlines.

The department says it will monitor Delta’s policy to make certain "it preserves and respects the rights of individuals with disabilities who travel with service animals". But it adds that "airlines are not required to accommodate unusual service animals, such as snakes, reptiles, ferrets, rodents, and spiders".

It isn’t clear what has spurred the increase in animals on planes in recent years. In some cases, airlines have banned certain breeds of dog from cargo holds due to the stress those animals experience in flight.

There has been a proliferation of online screening sites to allow passengers to "diagnose" anxiety or other disorders and offer a document designating their pet as a support creature.

Morrow says Delta will be interested to see the effect on service animal volume after the policy is enacted.

Rival American Airlines echoes the carrier’s concerns and praised the new rules.

"We are looking at additional requirements to help protect our team members and our customers who have a real need for a trained service or support animal," it says. "Unfortunately, untrained animals can lead to safety issues for our team, passengers and working dogs onboard aircraft."