Blue Birds

Henry David Thoreau wrote that the bluebird “carries the sky on his back.”  Although this poetic description referred to the Eastern Bluebird, the meaning could just as easily be applied to two other commonly seen, predominately blue birds that are found throughout the southeast.  The trio of common “blue birds” in Mississippi includes the Indigo Bunting (Passerina cyanea), the Blue Grosbeak (Guiraca caerulea), and, of course, the familiar Eastern Bluebird (Sialia sialis). 

If any of these three birds has a claim to the distinction of carrying the sky in its plumage, it’s the Indigo Bunting—the male of this species can seem to change hues as quickly as the spring sky can fade from clear blue to a duller gray over the course of an afternoon.  Although any blue coloration present in feathers is the result of light reflecting off of the structure of the barbules, the Indigo Bunting’s appearance is especially changeable.  The reason for this is that the feathers are iridescent, catching different amounts of sunlight to appear any shade from blue-black to bright turquoise.  In contrast to the male, the female Indigo Bunting is a much subtler brown, with hints of blue in the wings; this more subdued coloration helps camouflage her at the nest, which is generally placed in a small tree or shrub.  In fact, thickets, woodland edges, and overgrown fields are the favorite environments of this sparrow-sized member of the cardinal family, and, like cardinals, it will come to backyard bird feeders for sunflower seeds and white millet.  Its relatively thick, stout bill aids it in cracking hard seeds, but, like many birds, it also feeds on insects.  During the spring and summer, the excited, up-and-down warbling song of the male bunting cues observers in on its presence—helpful, considering how difficult it can be to catch a glimpse of the vibrant blue bird when it is hidden in vegetation.

Singing male Indigo Bunting in the sunlight.

Male Indigo Bunting on an overcast day.

Female Indigo Bunting

The Indigo Bunting’s larger cousin, the Blue Grosbeak, lacks the eye-catching iridescence of the bunting, but it is also a stunning bird.  The plumage of the male grosbeak is a deep, royal blue with brown bars on the wings and a black “mask.”  For the same reason as the female Indigo Bunting, the female grosbeak is more cryptically colored: brownish gray, with a touch of gray-blue on the wings.  “Grosbeaks” are aptly named—their dark-colored, conical beaks are very stout and large, and point to their relationship with the well-known Northern Cardinal, which also has a large bill.  They can be found in the same habitats as the Indigo Bunting, but usually in much smaller numbers.  However, in spring and summer, it is not uncommon to see these striking birds helping themselves to feeder offerings, bringing delight to observers who realize that their backyard visitors are not simply oversized Indigo Buntings.  Once learned, the song of the Blue Grosbeak is quite different from that of the Indigo Bunting; it is a series of throaty, rolling warbles that befit this larger, less hyperactive bird.  Blue Grosbeaks may be less jumpy than their smaller cousins, but anyone who has seen the males battling for territory in the springtime, chasing each other through the underbrush, knows that they are far from lethargic!

Male Blue Grosbeak

Female Blue Grosbeak carrying nesting material!

Nearly everyone has heard of or seen the bluebird, known to some as the “bird of happiness.”   Unlike the other two “blue birds,” though, the Eastern Bluebird—washed with vibrant blue on the back—has a rust-colored breast fading into a white belly.  Female bluebirds have a similar pattern, but with more subdued coloring.  The contrasting palette of colors makes this species difficult to confuse with anything else, and the song—a short, lilting warble—is a familiar sound in rural areas.  Open woodlots, abandoned fields, and pastures all provide habitat for Eastern Bluebirds, which nest in rotting posts, snags, and the bluebird nest boxes constructed especially for them.  Bluebirds’ diet consists mostly of insects and berries that they find in their natural habitat, although they will also occasionally come to backyard feeders for suet, mealworms, and fruit.  Unlike the Indigo Bunting and Blue Grosbeak, the Eastern Bluebird is a member of the thrush family, which includes such familiar birds as the American Robin and Wood Thrush.  Because bluebirds—like robins—lack spots on their breasts, they do not greatly resemble thrushes at first glance; however, their slim, slightly curved bills, upright posture when perching, and tendency to flutter their wings all point to this relationship.  Interestingly, bluebird young look far more like their thrush relatives.  They have streaked and speckled brown plumage, with blue only in the wings and tail. 

Male Eastern Bluebird

As for seasonal occurrence, the Eastern Bluebird can be found year-round in the state, and the Blue Grosbeak and Indigo Bunting are present during the breeding season.  In a way, we are fortunate that these three “blue birds” are common and widespread across the southeast.  About thirty years ago, Eastern Bluebird populations were declining due to loss of nesting cavities and competition with invasive European Starlings and House Sparrows.  Concern over the bluebird’s plight led many people to construct nest boxes for them, which helped increase the population to a healthy level today.  The Blue Grosbeak is also doing fairly well—it has even expanded its range northward in recent years.  The Indigo Bunting is declining across many areas of its breeding range due to habitat changes, but it seems to be maintaining relatively healthy populations regardless of this fact.  Because it does not use heavily forested habitats, the bunting has fared better than many songbirds, but both it and the grosbeak are at risk from destruction of habitat on their wintering grounds in Central and South America.  Hopefully, measures taken to prevent habitat destruction in both North and South America will ensure that these three species of “blue birds” continue to thrive, bringing welcome touches of sky to the earthly environments that they inhabit.

Snapshot of Autumn

There are so many rapid changes in the fall season that it can be hard to keep up with them all: temperatures decreasing; daylight hours steadily shortening; leaves turning yellow, red, orange, and brown; herbaceous plants dying in the fields; birds, butterflies, and dragonflies migrating; animals of all sorts fattening up; etc.  Taking photographs of nature helps me to track some of these ecosystem-level changes and cycles.  In the neighborhood, many of the wildflowers, including giant ironweed (Vernonia gigantea), a gorgeous native plant, have gone to seed.  

 

giant ironweed with seeds

 In August, these ironweed plants looked like this:

ironweed in August

However, as you can see in both the top photo and the one below, some of the ironweed is still flowering.  This species blooms through the late summer and into the fall.  Its flowers and leaves provide food for insects, and the seeds attract several species of birds.

September ironweed blossoms

Not all of the wildflowers are past their peak.  The goldenrod (which is probably the tall goldenrod, Solidago altissima), growing among the greenery of the woodland edges, has such vivid yellow flowers that it almost seems to glow.  These autumnal plants will probably continue to bloom for at least another month.

goldenrod

The toll that the long season has taken on some of the insects and spiders in the area can be clearly seen.  A common wood-nymph butterfly, a species typically found around shaded forest edges, looks a little the worse for wear.  The damage to its wings is, in all likelihood, the result of a few narrow escapes from birds.

common wood-nymph

One of the many orb-weaver spiders hanging around in the mid-level vegetation is missing legs: two of them seem to be entirely gone, and about half of a third one has also been amputated.  I don’t know whether this damage is from a bird or from something else, but, despite its disability, the arachnid is apparently still managing to eke out a living.

orb-weaver

Even though I don’t know for certain what caused the spider’s injuries, it’s fun to speculate.  Who knows what the culprit might have been?  While a lot of the birds around here feed on seeds and fruits, many more are either partly or exclusively insectivorous—or, since spiders aren’t insects, maybe the more accurate term would be invertivorous (invertebrate-eating).  Anyway, Red-bellied Woodpeckers certainly could be fierce and daring enough to have done it, from what I’ve observed.  I doubt that I’ll ever forget the afternoon at Noxubee National Wildlife Refuge, over a decade ago, when I saw a Red-bellied Woodpecker and a Northern Cardinal zipping through the woods in hungry pursuit of a Luna moth.  Woodpeckers might not seem like the most agile of birds, but I can attest that this Red-bellied was quite maneuverable!  I never saw what became of the Luna moth, but maybe it managed to evade the predators.  

A much less hurried—for now, at least—Red-bellied Woodpecker clings to a lichen-covered branch.  No need to chase moths or nab giant spiders—there must be plenty of food to discover beneath the tree bark.

Red-bellied Woodpecker on branch

Eastern Bluebirds patrol the grassy areas under the power lines, hunting for insects.  Their large, dark eyes and “open” faces give bluebirds an appearance of inquisitiveness.  That may not be entirely a fanciful notion, though, since bluebirds are great at investigating every inch of their environment for food and nesting places.  Any crack, crevice, or hole of sufficient size in a tree, box, or fencepost might serve as a suitable bluebird nest spot, and all sorts of arthropods and fruits make up the species’ diet.

Eastern Bluebird

A short, squeaky sound that recalls the noise made by sneakers on a gym floor alerts me to the arrival of a Rose-breasted Grosbeak.  Then another one flies in, landing very close to the first.  It’s the peak migration time for this species, and these two individuals seem to be merely stopping over for a brief spell.  They remain in the tops of the trees along the creek run for only a few minutes before flying away.

The first of the grosbeaks lands.

Two grosbeaks -- the earlier bird is on the right.

The lower photo provides an interesting comparison between the two individuals.  The bird at the right is definitely a male, and at least two years old, given that it has bold black-and-white wings, extensive dark feathering on the head, and a very distinct breast patch.  However, I’m not so certain about the bird on the left.  It’s either a female or a hatching-year male.  In the spring and summer, older male Rose-breasted Grosbeaks have entirely black heads and bright rose-pink breast patches.  The McGill Bird Observatory does an excellent job of describing the variation in these birds’ plumages (http://www.migrationresearch.org/mbo/id/rbgr.html#ahymb), and their website is one of the sources I’ve perused in my attempts to figure out the age and sex of birds that I’ve seen.  As I’ve learned over the years, though, ageing and sexing birds isn’t always possible in the field.  Obviously, birds that don’t display sexual dimorphism, such as Northern Mockingbirds, can’t be definitively sexed in the field under most circumstances (including when they are singing, apparently, since both males and females participate in that activity), but there are more sexually dimorphic species than you might think that can nevertheless befuddle observers.

Speaking of mockingbirds, both they and their close relatives, Brown Thrashers, are pretty vocal and active this time of year.  Unlike the mockingbirds, the thrashers aren’t singing right now (in the southeastern part of their range, they typically sing from March to May—and, in case you’re wondering, the females apparently do not sing), but they make their loud chak! calls on a regular basis as they forage in the dense thickets.  

 

Northern Mockingbird

Brown Thrasher

Both of these species, along with bluebirds, woodpeckers, and many others, will remain in this area through the winter.  Certain other birds, such as the Rose-breasted Grosbeak, show up here for only a very short time.  It’s the transitory nature of the season that can make it so simultaneously frustrating and exciting!

Out with the Old, in with the New

Rainwater from the showers of earlier that day, March 25, spattered from the newly-emerged leaves on the neighborhood trees and flowed down the roadside drainage ditches.  Most of the low-lying yards in the neighborhood held puddles of at least an inch or two deep.  Still, it wasn’t raining now, so a couple of family members and I decided to take advantage of this lull in the drizzly weather to exercise a little.  As we walked along the roads, Brown Thrashers chattered from their secluded perches in the shrubby woodlots.  

Brown Thrasher

The thrashers had been doing this for the past month or so, actually; like their close relatives, the mockingbirds, they’re typically early nesters.  So are Eastern Bluebirds.  A couple of pairs of these birds displayed their gorgeous cobalt-blue plumage as they flitted around the open fields, probably seeking out cavities in the large oaks and sugarberry trees that might serve as nest sites. 

Eastern Bluebird on wire

As I made my way down the road, multiple Carolina Chickadees and Tufted Titmice sang loudly from the woods all around the neighborhood.  In all likelihood, the bluebirds in this area compete with these two species and a variety of other animals, including squirrels and nuthatches, for nest sites.  I’m not sure that the forests here are quite swampy enough for another small, cavity-nesting bird, the Prothonotary Warbler, but since it’s nearly time for these yellow-and-blue birds to be winging their way back to their breeding territories, I suppose I’ll find out soon enough.

A brief sequence of wheezy notes sounding from deep within the cedar thicket made me stop for a moment.  Was that a Black-throated Green Warbler?  I pished loudly for a few seconds, then heard the call again.  No, it was the first few notes of a Ruby-crowned Kinglet’s song, the entire phrase sounding like Sisisisi see see see liberTY liberTY liberTY—all things considered, a boisterous song for such a tiny bird.  Although kinglets start singing during March and April in Mississippi, they breed elsewhere, migrating to Canada, the very northernmost United States, or the western U.S. to claim nesting territories.  Unlike most of the other birds I saw on the walk, the kinglets will soon be moving on.  I’m glad to have them around for a few more weeks, anyway.  That also goes for the Yellow-bellied Sapsucker that gave one squealing call from the trunk of a large sugarberry tree and then quietly slipped out of view.

Ruby-crowned Kinglet painting

Obviously, migrating birds were not the only noticeable changes in the environment.  Vegetation flourishes at this time of year, and with new plant growth and rain typically comes an increase in insect abundance.  That seemed to be the case here.  A profusion of wildflowers—spring beauty, wild garlic, henbit, Carolina anemone, and others—covered the lawns, and new, green leaves showed on branches.   

Carolina anemone

The rain had also helped to dislodge wilting blooms from many of the flowering trees and shrubs; the redbuds were no longer fuchsia-colored, and stringy, greenish blossoms from the oaks dotted the pavement.  Eastern tiger swallowtail and cloudless sulphur butterflies darted out from the woodland edges where, only a few weeks ago at most, they had emerged from chrysalides.  Unfortunately, the rain and warmer weather also bring out less pleasant insects, such as mosquitoes and gnats, but that’s just part of life as spring rolls into the Southeast.