Chico’s second new bird of the year is a Canyon Wren, captured and banded at the Chico/Bird Conservancy of the Rockies banding station on 11 September 2019. This elevates the total number of birds recorded at Chico Basin Ranch to 344 species, possibly more bird species than at any other location in Colorado. Most birders hear Canyon Wrens before they see them and bird field guides show them, as their name implies, being confined to canyons.
However, ornithological literature tells us that in the Mexico part of their range, Canyon Wrens also occur in desert habitats, so it is not totally surprising to record a southbound migrant on Chico Basin Ranch. The song is well known by most birders, and it is worthwhile to listen to the distinctive song here.
The long, narrow, and decurved bill enables the Canyon Wren to probe in rock cracks mostly for spiders, but they also take beetles, bugs, ants, and termites. This entirely insectivorous species has a flattened cranium and a unique attachment of the cervical vertebrae to the skull, plus its tarsi are short–all adaptations allowing Canyon Wrens to investigate very narrow rock openings.
Besides investigating tiny cracks, they are also known to steal paralyzed invertebrates from the nests of mud dauber wasps.
Canyon Wren nests are unique, being built in bare, shaded recesses in rocks and composed at the base with twigs and then wool and/or hair are added on top. Both males and females are involved in nest building. One California nest was discovered to contain junk from a nearby office and it contained 100 matches, 500 pins, 600 paper clips, and other manmade materials.
The Canyon Wren is the 9th wren species recorded on Chico Basin Ranch which now includes all the wren species seen to date in Colorado.
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