Northern Parula in Fort Collins (Larimer)

[DAVID A LEATHERMAN]

This is both a heads-up and a late report.  Yesterday, November 14th, a friend of mine, Georgia Doyle, checked on a commotion in her neighborhood involving Blue Jays and many small passerines.  The subject of their wrath was an Eastern Screech-Owl.  Two of the upset birds are noteworthy in their own right or because of the date: a Northern Parula and at least one Ruby-crowned Kinglet. 

I checked out the site this morning and in the tree (some type of White Oak) in front of 813 Oak Street in Fort Collins was one Ruby-crowned Kinglet, no parula, no owl, and many aphids on the leaves.  Sound familiar?  I think the aphids are Clear-winged Oak Aphids (Myzocallis punctata).  One possible scenario that makes sense: the owl, which has long resided in this neighborhood, chose the tree for roosting because, like many oaks tend to do, it clings late to all its leaves, and, even better, this tree's crown is quite dense; some of the small birds such as the warbler and the kinglets chose the tree because it has lots of food in the form of aphids; while foraging they discovered the owl; their alarm was responded to by the jays; the jays drew in more reinforcements like nuthatches and others.

The heads-up is not to limit your aphid tree search (and possible late migrants that might be in them) to just pines in business parks.  Trees of all types that are sticky, shiny-leafed (or needled), dirty or sooty-looking, with yellowjackets, lacewings, and ladybird beetles flying about would be worth checking out. 

Dave Leatherman
Fort Collins