Pleistocene Phoebes (Sayornis sp.)

I frequently hear the call of the eastern phoebe (Sayornis phoebe), but I almost never see them.  So I was excited to photo a phoebe in my backyard last week.  My cat unsuccessfully stalked it while it was perched in a peach tree.  The bird landed on my fence, then picked off an insect on the ground and returned to the fence and ate it.  This is typical foraging behavior for phoebes.  They look for insects from above and drop to the ground to catch them.  Its mate observed this action from an higher limb.

Eastern phoebe on my fence.

https://www.allaboutbirds.org/guide/Eastern_Phoebe/sounds

Call of an eastern phoebe.

Phoebes belong to the tyrant flycatcher family or the Tyrannidae.  They are named for their aggressive behavior toward large predatory birds such as hawks and owls.  Phoebes mercilessly harass the larger birds until they leave the vicinity of the phoebe’s territory.  Phoebes live year round in my neighborhood–I hear their calls as early as February.  This species expands its range north during summer, and they do the reverse during winter.  They produce 2 broods per summer.  Although they prefer insects, they can subsist on berries and seeds when cold temperatures knock back insect activity.

There are 2 western species of phoebes–the black phoebe (S. nigricans) and Say’s phoebe (S. saya).  A common ancestor of all 3 species likely occurred all across North America about 5 million years ago.  Ecological changes associated with glacial/interglacial climate phases separated ancestral populations of eastern phoebes from their western cousins.  The same is true for a long list of bird species in North America.  There are eastern and western species of scrub jays, nuthatches, flickers, and many others.  Pleistocene-aged fossils of eastern phoebes have been excavated from Kingston Saltpeter Cave in Georgia, Bell Cave in Alabama, Natural Chimneys in Virginia, and Cheek Bend Cave in Tennessee.  Phoebes like to nest on natural or manmade structures, and caves provide favorable nesting locations, explaining why their fossil remains are often found in them.

Eastern phoebe range map.  Say’s phoebes occur almost exactly to the west of eastern phoebes.  Black phoebes are primarily a Mexican species.

There are 2 other species of tyrant flycatchers that occur or are supposed to occur in my neighborhood.  I often see eastern kingbirds (Tyrannus tyrannus), though I never hear them (the opposite of my experience with eastern phoebes).  Fossil evidence of eastern kingbirds has been found at 2 sites in Florida–Reddick and Vero Beach.  I’ve never seen a crested flycatcher (Myiarchus crista), perhaps because they prefer deep virgin forest where they can nest in hollow trees.

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