Connecticut Warbler, Oporornis agilis

Note: this post, while published, is a work in progress, as are all posts in this series, My Photo Life List. My goal is to photograph every species of bird that is seen on a regular basis here in Michigan, working from a list compiled by the Michigan chapter of the Audubon Society. This will be a lifelong project, that I began in January of 2013, and as I shoot better photos of this, or any other species, I will update the post for that species with better photos when I can. While this series is not intended to be a field guide per se, my minimum standard for the photos in this series is that one has to be able to make a positive identification of the species in my photos. The information posted here is from either my observations or the Wikipedia, the online free encyclopedia, however, I have personally shot all the photos appearing in this series.

 

Connecticut Warbler, Oporornis agilis

The Connecticut warbler (Oporornis agilis) is a small songbird of the New World warbler family.

These medium-sized warblers measure 13–15 cm (5.1–5.9 in) in length, with a 22–23 cm (8.7–9.1 in) wingspan. Connecticut warblers weigh 10 g (0.35 oz) when they fledge, attaining an average weight of around 15 g (0.53 oz) as adults. However, birds preparing for migration pack on more weigh to survive the strenuous journey and can weigh up to 25 g (0.88 oz). This species has light yellow underparts and olive upper-parts; they have a light eye ring, pink legs, a long tail, pale wing bars and a thin pointed bill. Males have a grey hood; female and immatures are more brown and have a whitish throat.

hey forage on the ground, picking among dead leaves, or hop along branches. Like most warblers, these birds mainly eat insects and similar small invertebrates. Specifically, they eat spiders, snails and caterpillars. They will also supplement their diet occasionally with seeds and berries.They are “skulking” birds that usually spend their time foraging within dense, low vegetation. Such behavior often renders them difficult to see well.

Despite its name, this bird only rarely visits Connecticut during migration. It was named by Alexander Wilson who observed the first classified specimen. They are fairly elusive birds, but it appears that their numbers may be declining due to loss of winter habitat.

Their breeding habitat is bogs or open deciduous woods near water, especially with poplar, spruce, tamarack or aspen, in central Canada and states bordering the Great Lakes. These habitats tend to be in rather remote areas that are hard to access for fieldwork; therefore, there is little data available on this species of birds. The nest is an open cup well-concealed in moss or a clump of grass. It is made of “dry grasses, stalk of weeds and horsehairs”.

Courtship begins right after the migrants arrive on their breeding grounds. It correlates with the time when males start to sing as this is how they court females. Couples have one brood per season. Connecticut warblers like to nest in thick understory where their young are protected from predators. Most lay in mid-June, though some populations have been observed to lay in July. Their eggs have a creamy color and they are speckled and blotched with chestnut and bay. Only females incubate. Fledglings are observed in late July and at the latest at the end of August. Both parents feed their young caterpillars, larvae, moth and berries.

It walks on the ground to forage insects and other sources of food. Its tail bobs up and down, which is reminiscent of wren and sandpiper behavior. When it comes to sociability, the Connecticut warbler is a solitary species; however, groups of about twenty-five will come together in the fall before migration. It also will join other species, such as Blackpoll warblers, to feed during the fall.

As mentioned earlier, the Connecticut warbler is an elusive species. Little is known about it outside of the breeding season as to this date, less than 25,000 individuals have been banded. These birds migrate to the Amazon Basin in South America in winter. Specimens have been observed in Colombia (north & southeast), Venezuela (northeast & interior), Guyana (at the border), and Peru (South). Connecticut warblers undertake different migratory routes in spring and in fall, an atypical behavior. In spring, they normally pass through the Midwest and only rarely migrate to the East coast, but in fall, larger numbers of migrating birds move through the East coast. Recently, the use of small tracking devices have enabled scientists to gather more data on the warbler’s migration routes. They have discovered some individuals fly over open water like the Blackpoll warbler. More specifically, they recorded a previously undocumented two day flight over the Caribbean to the Antillean islands. This correlates with sightings of Connecticut warblers that have occurred in Bermuda, St Thomas and St Martin. The island of Hispaniola is also a popular stop as it is rather remote due to past humanitarian crises. There, they make a minimum of 48 hour stop (it usually lasts 5–7 days) in the Caribbean. This long migration over open water calls for strong selective pressures. A comparative study between the Connecticut warbler and the Blackpoll warbler could help determine what selective pressures are present in these two species. This kind of migration also demands large reserves of fuel and this is why fat Connecticut warblers can be found on the East coast in early fall. It’s also the reason why they make several stopovers on their way South.

 

On to my photos:

So far, I have managed to shoot just three useable, but poor photos, of this species, in part, due to its elusive nature and the fact that it prefers dense growth to forage in. They were shot in May of 2016 while I was on vacation near Alpena, Michigan.

 

Connecticut Warbler, Oporornis agilis

 

Connecticut Warbler, Oporornis agilis

 

Connecticut Warbler, Oporornis agilis

 

This is number 211 in my photo life list, only 139 to go!

That’s it for this one, thanks for stopping by!

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