The couple were on a short-haul flight in California when they struck up a conversation by chance with two people seated nearby, not knowing they were officers from the California Department of Fish and Wildlife (CDFW).

They eventually confided in their fellow passengers that they were illegally transporting a green sea turtle skull, and showed the skull to them when they were sure airline officials weren’t looking.

The couple also talked about illegally hunting a mountain lion and a relative who they said had a trophy room full of taxidermised animals.

Following the chance conversation, the wildlife officers obtained search warrants for the homes of the couple and their relative, The Guardian reports.

They found a cornucopia of illegal hunting trophies — including parts of illegally-hunted deer, mountain lions, ringtail cats, barn owls and wolverines – in both homes.

The couple – 24-year-old Byron Lee Fitzpatrick and 28-year-old Shannon Lee Price – were convicted under state wildlife laws, given a one-year ban on hunting or associating with hunters, and fined $1,865 and $1,015 respectively, plus another $1,000 each in federal fines.

Their relative, 64-year-old Harry Vern Fitzpatrick, admitted possessing protected species and was placed on six months of probation, fined $605 and forced to give up his illegal collection.

Nathaniel Arnold, CDFW’s chief of law enforcement, said: “This case shows how important it is for our wildlife officers to be alert at all times.”