Favoritos de artificialfauna

Eating chicken food out of my bird feeder in Shelter Valley, CA
(Exact coordinates hidden because it’s all private property and my neighbors didn’t like people coming down the private road, sorry everyone)

Rather than just leaving this bird as Baeolophus species as I've done a few times in the past, I will give it the name of Hybrid Tufted X Black-crested Titmouse which is the way eBird handles this population.
In west Austin and westward we have typical Black-crested Titmouse as illustrated by an image I took about 25 miles west of this spot a few days ago:
http://www.inaturalist.org/observations/524714
Note the very black front of the crest and the very pale buff patch over the base of the bill.
About 25-30 miles east of Austin we have typical Tufted Titmouse which is familiar to folks all over the eastern half of the U.S. A shot I took about 30 miles east of the present location will illustrate our typical Tufted Titmouse with the the gray crest and the black patch above the base of the bill:
http://www.inaturalist.org/observations/167099
In the eastern half of Austin as well as south to Gonzales, Texas and north up to near Dallas, in the range of overlap between those two species, we get a hybrid swarm. Some birds show a little black in the crest, others do not, but all have a rusty colored or dark rufous patch above the base of the bill. I am confident that these birds are freely breeding and reproducing among themselves and I do not believe it is a situation where multiple pair combinations of Black-crested and Tufted parents produce these birds. I am unaware if this is documented scientifically or not, but this zone of hybrids or inter-grades is too wide, in my opinion, to suggest otherwise. I know this is long and windy, but I am often asked about this situation and I thought I would post this record with several images showing some variation among some of these interesting birds so that when asked what they look like I can simply refer people to this record. Note that some of these birds have a little dark streaking in the crest while others do not, but also note the dark rufous patch above the base of the bill which is not like that of Black-crested or Tufted.

Flickr:
www.flickr.com/photos/157014451@N04/49086359516/in/datepo...

en.wikipedia.org/wiki/European_crested_tit

ru.wikipedia.org/wiki/%D0%A5%D0%BE%D1%85%D0%BB%D0%B0%D1%8...

The photo is of a Violet-green Swallow in a nest box with 5 Western Bluebird nestlings. The Violet-green Swallows have returned after migrating and are looking for cavities to nest in. The swallows won't harm the nestlings, and there are reports of swallows actually assisting in feeding the nestlings.

Violet-green Swallows and Ash-throated Flycatchers are the late nesters and often have to use whatever cavities are available. I've been finding both Tree and Violet-green Swallow nest starts in boxes from which other species have fledged and before I had a chance to clean the used nest out.

This is another example of the competition among birds that occurs for cavities to nest in. I added another nest box nearby in hopes that the swallows will use it.

Here's the swallow observation: https://www.inaturalist.org/observations/79034267

📸: By Lee Pauser

This observation was part of a nest box trail done in conjunction with the California Bluebird Recovery Program (CBRP), which runs the Cavity Nesters Recovery Program (CNRP). CNRP involves many volunteers across California who establish and monitor nest box trails for cavity-nesting birds. During the breeding season, these boxes are checked weekly for parasitism, predation, number of eggs, nestlings, and number of young fledged. Then at the end of the nesting season, volunteers submit their results to CBRP. We compile these results and submit them to the Cornell Lab of Ornithology’s NestWatch program and other interested organizations.