Friday, May 18, 2012

Couch's and Tropical Kingbirds

Our recent stay in south Texas resolved a complicated birding conundrum for me. In 1964 I visited the Santa Ana National Wildlife Refuge and listed a Tropical Kingbird. At that time that identification was the only one possible. Turns out that a second species, the Couch's Kingbird, was described in 1853, but was considered to be just a race of the Tropical Kingbird since 1874. Like many young birders, I was unaware of bird races when I made my initial ID.

In 1966 ornithologists split the Tropical Kingbird into two species, the Tropical, found in southern Arizona and elsewhere in South America, and the Couch's Kingbird, found in southern Texas south into northern Central America. In the 1980s, because of their ranges, I was able to add Couch's Kingbird to my life list.
The reason for this split was that each species has a distinctive call. This year, when we entered the Santa Ana Refuge, we clearly heard Couch's Kingbirds. Their call reminded me of the "Beer" part of the Olive-sided Flycatcher (see last post). It was good to finally REALLY see a Couch's Kingbird. (We saw many Tropical Kingbirds during our research in Peru and Ecuador.)

The situation is more complicated. In the 1990s, Tropical Kingbirds began breeding in southern Texas. During our March 2012 visit, Erika and I found a Tropical Kingbird near the National Butterfly Center near Mission. The bird clearly had a different call from the Santa Ana birds. Thus I added the Tropical Kingbird to my United States list.
In this post, the first two photographs are of different Couch's Kingbirds at Santa Ana National Wildlife Refuge. The final photo is of the Tropical Kingbird we saw and heard near the National Butterfly Center. Although the species overlap in habitat, notice that the two Couch's Kingbirds are surrounded by woodland, whereas the Tropical is in the open on a telephone wire. Sources for this account include Brush (1999) and Stoffer and Chesser (1998). The song links in this post are used with permission from Thayer's Birds of North America DVD Gold Edition V5.5.

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