Wildlife Monographs

Red Fox Predation on Breeding Ducks
in Midcontinent North America

Table 7. Incidence of ducks at red fox rearing dens visited in duck nesting ground sample areas of midcontinent North America, 1968-73.

				North Dakota		South Dakota
		Iowa	Minn.- Wis.	East river^a	West river^b	East river^a	West river^b
Years		69-70	68-70	68-73	68-70	68-70	68-70
	No. fox dens	193	52	648	91	109	298
	No. ducks at surface of dens	2	20	1164	23	65	159
Fox predation rate index (surface ducks/den)		0.01	0.38	1.80	0.25	0.60	0.53
Dens with ducks on surface (%)		1	31	63	23	36	33

^aEast of the Missouri River.
^bWest of the Missouri River.