Thursday, April 10, 2014

Wrentit

Wrentit
Wrentit. March 9, 2014. San Marcos, California. Greg Gillson.
The Wrentit is found in chaparral and evergreen shrubs from the mouth of the Columbia River in Oregon south to the middle of Baja California (Norte). It's an odd little bird with no close relatives, thus the reason it gets shuffled around into different families. It is neither a wren nor a tit (chickadee). It is currently placed in the Babbler family, but recent DNA research may indicate that it has closer relatives in the Old World Warbler family. In either case, the Wrentit is the only New World member of either of these families of otherwise Old World birds.

More often heard than seen, this species skulks in dense bushes near the ground.

The next photo shows something interesting in regards to molt and aging. See the barely visible numerous evenly-spaced bars across the tail? Those are growth bars. Since all the tail feathers show the growth bars all the tail feathers grew in at once. This could happen if the bird lost its tail, somehow--an attack by cat or bird. However, it is more likely that these tail feathers grew in all at once during the prejuvenile molt. In other words these are the first set of feathers to grow in from the downy chick stage.

The bars themselves are caused by differences in feather growth between day and night. It looks like it took about 2 weeks to grow in the tail, judging from the number of growth bars. March 9 is the photo date. It seems early, but the best explanation is that this is a recently fledged young bird. If so, then the bird must have hatched before the 25th of February.

Wrentit with tail growth bars
Wrentit with growth bars on tail. March 9, 2014. San Marcos, California. Greg Gillson.
The Wrentits here in southern California are much paler gray-brown than the rich ruddy brown ones I am used to seeing on the Oregon Coast. Take a look at an Oregon bird below.

Wrentit
Wrentit. July 30, 2011. Lincoln County, Oregon. Greg Gillson.

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