Coyotes (Canis latrans) rely on visual cues to detect prey, but the practic
al impact of such cues on the effectiveness of lures and attractants is poo
rly understood. We designed the present experiment to test whether color wo
uld increase detection and activation of sodium cyanide ejectors (M-44s) by
free-ranging coyotes. At each of 4 study locations, we selected 6-14 exper
imental sites and then deployed unarmed M-44s at each site. We cleared a l-
m-diameter circle around each device so that we could record wildlife track
s. We placed 2-cm pieces of white-painted, rubber soaker hose over the cyan
ide cartridge sleeves of half of the M-44s. We placed sections of black-pai
nted, rubber soaker hose over the cartridge sleeves of the remaining M-44s.
We visited each site at 2-day intervals to record whether M-44s had been t
ripped. We also recorded species of wildlife that left tracks at each site,
and general weather conditions. We categorized both visits and pulls by co
lor and background type. Although number of visits did not significantly di
ffer among sites, number of pulls did. Pulls were most frequent for white-t
opped M-44s against a no-snow background. Pulls were next most frequent for
black-topped M-44s against either snow or no-snow backgrounds. White-toppe
d M-44s against snow were not pulled. When the species visiting M-44s were
examined, we found that more species visited sites and pulled M-44s in Ohio
than Utah. We conclude that distinctive colors can be used to enhance M-44
pulls. Our finding that a number of species activate M-44s is inconsistent
with other reports, and a topic for future research.