The year that my wife Dawn was able to spend the spring and summer with me in Tikal, Guatemala (the first year after we were married), we began a very interesting study of Swallow-tailed Kites (about which more at another time). This meant sitting for long hours observing their treetop nests, and much of this sitting was done on one or another of the temples or other Maya ruins (which got us up to the level of the canopy). Dawn did the lion's share of these observations (as I was often off conducting various other researches).
During these observations, it was not unusual for Dawn to have a number of young Gray Foxes (Urocyon cinereoargenteus) playing in close proximity to her. They had been raised in a den in the water-collecting tunnels that the Mayas had included in their buildings. Besides enjoying the company of these cute little fellers, Dawn was able to document a previously undiscovered behavior for this species.
Gray Foxes are considered monogamous and among the least social of the dog family. So it was with some surprise that we discovered that two lactating females were sharing the same den at Tikal's North Acropolis. Litter size in this species ranges from 2 to 6, but we saw as many as 11 pups together at the same time. Although Red Foxes (Vulpes vulpes) and other canids have been seen with such shared dens, it had never before been seen in Gray Foxes. (We wrote it up and published it in the Journal of Southwestern Naturalists.)