Howdy, friends.  This week’s bird follows on from last week’s, we’ve got ourselves another redstart.  The American redstart is a truly tiny warbler that breeds in large swaths of the US and Canada. It winters in southern California as well as the very bottom of Florida, the coasts of Mexico, the Antilles islands, and large chunks of Central and South America.  Males weigh between 7.2 and 8.6 grams (.25-.3 oz), being lighter in the winter.  Females weigh between 6.9 and 8.7 grams (.31-.24oz), losing about 20% of their weight.   Breeding males are a striking orange color due to possessing red and yellow carotenoids which combine to form orange.  Juveniles and females only have yellow carotenoids.  

The American redstart has on two occasions been observed breeding with the magnolia warbler, with which it shares a genus.  Examples of this were recorded in Ohio and Quebec.  In both cases, the father was a redstart and the mother was a magnolia warbler.  

During the breeding season, the American redstart prefers open canopy forests, where the trees are not so dense as to block light to undergrowth and the forest floor.  These forests are usually deciduous, and can be second growth, or forests that have regrown after natural or human caused catastrophic events.  In line with its preference for less dense forest, it is often found at forest’s edge.  This bird feeds primarily on insects as well as some berries.  It forages in the middle and lower areas of native vegetation, often alongside flocks of other warblers.  Like last week’s painted redstart, it hops around flashing its wings and tail, startling and flushing out its meal with a sudden appearance of bright colors. My favorite fact this week is that our subject is often called “candelita” or “little candle” in Latin America due to its bright, colorful plumage.

While migrating and wintering in points south, it lives in a variety of habitats, including a lot of scrubby areas.  While moving south and once it arrives, it will live in any wooded area, although it avoids agricultural areas devoid of trees.  It can be found in shade-grown coffee plantations and sometimes at elevations of up to 3,000m, or about 9,800ft.

American redstarts prefer to nest in open woodlands or scrub, often near water.  Unlike the painted redstart, which tends to nest on the ground or on a cliffside, building a ramshackle nest of branches and twigs, the American variety builds a “neat, cup-shaped nest” in a bush or tree.  Males in their first breeding season have low success, less than 50%, possibly because they retain their juvenile yellow plumage despite being old enough to get down.  Females are more successful in their first breeding season.  Although these birds are primarily monogamous, around 25% of males are able to hold onto multiple territories occupied by multiple female partners.  Even within monogamous pairs, there is a 40% chance that the chicks being raised by a given pair have a different father than the male of the pair.  I haven’t done this in a while, but here is an excerpt with more info: 

“The intensity of the male’s coloration predicts their success at holding territory in their non-breeding, winter locations in the Caribbean, the probability that they will be polygynous, and the proportion of offspring in their nests that they will themselves father. Males are invariably very territorial and the superior males occupy the best habitats, such as moist mangroves, while inferior males occupy secondary habitats such as dry scrub forests.”

The American redstart is listed as “of least concern” by the IUCN due to its large territory and some evidence that its numbers are increasing.  As always, however, climate change and human activity may put pressure on its preferred environs.  Have a good weekend, everyone.  Take care of yourselves and others, and spare a thought for your fearless host, who is bravely reporting to work on Saturday morning.

Links: https://tinyurl.com/2s47by8f, https://tinyurl.com/32rxe88n, https://tinyurl.com/y76xpdds, https://tinyurl.com/3anner76, https://tinyurl.com/muejxu4j