Service and emotional support animals are a common sight to see nowadays, whether it be somewhere as commonplace as on the street or in a grocery store, or somewhere as unexpected as on an airplane crossing the globe.

Due to an increase in the types of animals being brought onto flights, accompanied by an increasing number of incidents and customer complaints related to service and emotional support animals, Delta Air Lines recently announced a crackdown on the practice, explaining that:

"Customers have attempted to fly with comfort turkeys, gliding possums known as sugar gliders, snakes, spiders and more. 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 announcement comes in response to an 84 percent increase in instances of animals biting other passengers, defecating, or urinating on flights -- actions that likely cause a generally large discomfort for others sharing the flight, to say the least.

And it's not just Delta Air Lines with this problem -- just this week an artist's emotional support peacock (which had a paid seat from Newark to Los Angeles) was turned away by United Airlines.

As for Delta, beginning March 1, 2018, passengers traveling with service or emotional support animals will be required to file documentation with the airline at least 48 hours before their flight. It's expected that the other major airlines will also follow Delta's example.

But following the release of Delta's statement, a number of groups have voiced significant displeasure with the rules, even going so far as to call it discrimination. The National Federation of the Blind, for instance, feels that Delta's policies violate the Department of Transportation's Air Carrier Access Act.

"We are particularly troubled by the requirement that guide dog users submit paperwork to Delta forty-eight hours before flying. Travelers without guide dogs are not required to plan their travel forty-eight hours in advance. Furthermore, guide dog users will no longer be able to fly Delta in family, medical, or other emergencies. We believe that this forty-eight hour requirement is both unnecessary and unlawful."

The group has asked for talks with Delta to align on a better policy that meets both parties' needs, where passenger safety and convenience is prioritized among both service animal owners and otherwise.

The Guide Dog Foundation and America's Vet Dogs also has a problem with Delta's new requirements. In a joint statement, the organizations said,

"The Guide Dog Foundation and America's VetDogs understand the problems raised by individuals who pass off pets as service or emotional support animals -- these are issues faced every day by people with disabilities -- and with the difficulties airlines face when these passengers attempt to travel with these animals. However, we do not believe the solution lies in creating additional burdens for people with disabilities who fly with their well-trained guide dogs, service dogs, or hearing dogs."

While it's not clear what the ultimate resolution will be, I suspect that the days are numbered for anyone planning to bring their emotional support hedgehog, ferret, snake, goat, turkey, pig, or other prohibited animals along on their next flight.