Some of our newly arrived coyotes(last 10 years or so) are going over 50 pounds. No wolf, but they often run in pairs and 3's and I have seen them running deer. I doubt they have much luck on any but the weakest and fawns. I do know they do a hurting on fawns though... Bears eat piles of fawns and bobcats take a few as well. I saw a bobcat last year that easily went 50 plus pounds. I am sure it takes yearling deer here and there. Still, without hunters the deer population would blow up so fast.
On the feral cat note, they are actually the number 2 cause in songbird decline after habitat destruction. When I predator call, if a feral cat comes in, it doesn't leave...
One of the nastiest birds is the brown-headed cowbird. It is a nest parasite of other song birds. It will follow a song bird around(vireos, bunting, kinglets, etc) until it finds their nest. It will then slip one of their eggs in. Their eggs hatches much faster than other song birds. When that baby hatches, within a couple days it has rolled the other eggs out. If the other birds have already hatched, it quickly out grows them, takes over and literally starves them to death... A nasty little bird that destroys countless song bird nests each year. Legally they are protected as a songbird, but they are on the SSS plan in my book. Again, they were only native to the plains states and followed herds of bison. However, as man cut the forests down and introduced new domestic animals to North America, the cowbird spread throughout most of North America and with that spread it has wreaked havoc on song bird populations... Habitat destruction is a far bigger concern, but cowbirds sure as heck don't help the cause!
