In studies of dead birds that died from West Nile Virus, about 80% of the dead birds were corvids, i.e., crows, ravens, rooks, jackdaws, jays, magpies, treepies, choughs, and nutcrackers. Yet these avian species do not seem to be in the same steep decline as ruffed grouse.
Nest predation has always been a factor in the survival of ground nesting birds, and trapping may have helped to limit the numbers of nest predators. But it is almost a certainty that the reduced numbers of young kids running traplines has been more than offset by a vastly increased number of Eastern Coyotes that also eat young racoons, feral cats, foxes, etc. Trappers run their traplines for a limited number of weeks each winter. But coyotes hunt and kill every day of the year.
