https://en.wikipedia.org/wiki/M44_(cyanide_device)
The M44 cyanide device (also called a 'cyanide gun' or a 'cyanide trap') is used for the elimination of coyotes, feral dogs, and foxes. It is made from four parts: a capsule holder wrapped with cloth or other soft material, a small plastic capsule containing 0.88 grams of sodium cyanide, a spring-powered ejector, and a 5-7 inch stake. To install the trap, the stake is first driven down into the ground, and then the capsule is put in the holder, screwed onto the cocked ejector, and secured to the stake. The wrapped capsule holder is smeared with scented bait to attract coyotes and make them bite and pull on it. (The use of a bite-and-pull action makes the trap less likely to be set off by non-canine wildlife.[1]) When the trap is triggered, the spring propels a dose of sodium cyanide into the animals's mouth, and the sodium cyanide combines with water in the mouth to produce poisonous cyanide gas.[2] In addition to the cyanide, the capsule contains Day-Glo fluorescent particle marker (orange in capsules used by the Wildlife Services, and yellow in capsules prepared for other users) .[3]
Whoa.
The M44 is in frequent use by the USDA Wildlife Services in their programs to eliminate coyotes. For example, in 2016, out of the 76,963 coyotes that Wildlife Services killed, the M44 was used to kill 12,511 of them (16%).[5]
This is totally insane to me.