Ranchers and wildlife managers generally agree it sometimes is necessary to control predator populations. But when control measures involve poisons, the possibility of unintended consequences raises red flags among the general public.
Such was the case when Texas recently announced plans to use a Warfarin-based pesticide to control feral hogs. Now, concerns over the safety of “M-44” predator-control devices have pushed the USDA/APHIS Wildlife Services (WS) to issue additional guidance and an expanded review of the devices.
According to WS, the M-44 ejector device consists of a capsule holder wrapped with cloth, wool, or other soft material; a cyanide capsule (small plastic container holding less than 1 gram of sodium cyanide); a spring-activated ejector; and a five- to seven-inch tubular stake. In the field, a bait or attractant tempts an animal to pull on the capsule holder, which then ejects sodium cyanide powder into the animal’s mouth. The sodium cyanide quickly reacts with moisture and releases hydrogen cyanide gas. Death is very quick, normally within one to five minutes after the device is triggered, according to WS.
While the device apparently is effective against livestock predators such as coyotes and feral dogs, its use raises concerns among environmental groups, wildlife enthusiasts and pet owners. Recent news stories have documented accidental cyanide poisonings of pet dogs and possibly humans. In an Idaho case, a pet dog died after encountering an M-44 device, and the 14-year-old boy walking the dog suffered symptoms suggesting exposure to cyanide.
According to The Sacramento Bee, U.S. records show more than 3,400 animals were mistakenly killed by M-44s between 2006 and 2012.
The new directive from WS calls for more durable and visible signage to make it clear to people that M-44s have been set in an area, and these signs will now be placed within 15 feet of each device, rather than the 25 feet established by Environmental Protection Agency (EPA) restrictions. One elevated sign will be required for each device placed.
WS also has established a ½ mile perimeter for M-44 devices, along with a policy to proactively communicate with residents near this radius and to document that this notification has taken place. WS will use maps, GPS, GIS and other available technologies to assure devices are placed appropriately on public and privates lands, and to identify the perimeter, according to a USDA news release. In addition, WS will continue to require written approval from the owner or cooperator of land where any M44 device is to be placed.
USDA believes the devices play an important role in protecting livestock. In a 2015 survey of producers, the National Agricultural Statistics Service (NASS) found that coyotes nationwide killed an estimated 118,032 sheep and lambs, valued at an estimated $12.1 million and $20.4 million, respectively for all predators. Dogs, the second most common livestock predator, were credited with 21.4 percent of predator losses in adult sheep and 10.3 percent of predator losses to lambs.
Read more about the M-44 device from USDA/APHIS/WS.