Red-shouldered Hawks

It wouldn’t seem quite like autumn without the hawks and falcons hunting along fencerows, darting through the woods, or soaring on the breezes. I have been seeing a number of raptor species lately, including the swift and agile Cooper’s Hawks, the slower but more powerful Red-tailed Hawks, the wary and fidgety American Kestrels, and the high-soaring (at this time of year, as they migrate) Broad-winged Hawks. But the species that I see most frequently in my neck of the woods is actually none of these: it’s the Red-shouldered Hawk, a member of the genus Buteo and a close relative of the Red-tailed and Broad-winged Hawks. Red-tailed Hawks might be more common and widespread, but the types of habitats near my home are simply better for Red-shouldereds, and that’s fine with me. 

Unlike Red-tailed Hawks, Red-shouldered Hawks tend to prefer low-lying, heavily wooded environments. They are commonly found year-round in many hardwood and mixed forests throughout southeastern North America, and, in the fall and winter, this southeastern population is boosted by migrants from the northeastern United States and southeastern Canada. The difference in habitat between Red-shouldered and Red-tailed Hawks means that their dietary preferences are a bit different, as well; like Red-tails, Red-shouldereds eat lots of small mammals, but, because they inhabit denser, swampier woods, they’re also likely to catch frogs, snakes, and lizards. However, even though they’re primarily forest hawks rather than field hawks, they will often hunt from powerlines and prominent snags at the borders of woodlands and fields. Presumably, this makes it easier for them to find and catch their prey, given that they lack the maneuverability of species such as the Cooper’s and Sharp-shinned Hawks.

Appearance-wise, Red-shouldered Hawks are a little smaller and slimmer than Red-tailed Hawks, and, of course, they lack the brick-red tails that adult Red-tails have. They DO have reddish-brown “shoulders,” but this usually isn’t the most obvious field mark. The barred, reddish-brown breasts, black-and-white banded tails, and black-and-white wings on the adult hawks are far more noticeable features in the field. As you can see in the first of the two photos below, there are also vertical breast streaks on top of the chestnut-colored horizontal barring. Juvenile Red-shouldered Hawks look fairly similar to the adults, but have drabber, browner feathers and lack reddish barring on their breasts. In flight, both adults and juveniles show “wing windows,” which are essentially just pale crescents near the wingtips. This is a great field mark to look for if a hawk is soaring overhead. 

The rusty breast feathers on this adult hawk are a useful field mark.

Juveniles have browner plumage and streaks on their breasts.

Crescent-shaped wing markings are visible on this soaring adult hawk.

At this time of year, the immature hawks have probably been independent from their parents for several months, so they’re essentially competing with adult hawks for food and territory. If they survive the winter and later become breeding adults, then they will likely build their nests in large trees in the woods and lay two to five eggs per brood, with only one brood per season. Apparently, little is known about Red-shouldered Hawk nesting habits, so if you happen to spot a breeding pair next year, there is a chance that your observations could be of significant scientific value! In the meantime, enjoy watching Red-shouldered Hawks and other raptors as this year wanes. 

Source:

Dykstra, C. R., J. L. Hays, and S. T. Crocoll (2020). Red-shouldered Hawk (Buteo lineatus), version 1.0. In Birds of the World (A. F. Poole, Editor). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bow.reshaw.01

 

Summer Redbirds

While the Northern Cardinal is the most familiar “redbird” in southeastern North America, the region hosts another rosy-plumaged songbird species that is also quite common, if somewhat more secretive: the Summer Tanager.  Catching a glimpse of one of these migratory birds may be difficult at times, but, if you learn to recognize their vocalizations, you may find them in a lot of places that you might not have expected.  The main call of this species is a dry pik-i-tuk-tuk, while the song is a slurred, throaty warble—smoother than the more separated phrases of the American Robin.  Because Summer Tanagers—and most tanager species, in general—tend to forage in the middle and upper branches of trees, seldom venturing close to the ground, the sounds that they make really are the most obvious signs of their presence in a given area.  Mixed forests, particularly pine-oak woods, are the preferred habitats for this species.

If you do manage to spot a Summer Tanager after hearing its song or call, it’s generally pretty easy to tell whether the bird is male or female.  Fully adult males have rose-red feathers all over.  Adult females are more variable, and can be anywhere from a slightly greenish yellow to an orange-yellow with hints of red.  

Adult male Summer Tanager

Female Summer Tanager

Notice that I said it’s generally pretty easy to tell the sexes apart.  Identification becomes slightly more complicated in the fall, when first-year males can have smatterings of red in their plumage or even an overall orangey appearance, just like female tanagers.  However, the young males usually have more red on the undertail coverts than the adult females do, so it’s sometimes possible to tell them apart.  Additionally, although some first-year female Summer Tanagers may look almost identical to some adult females, it’s more typical for them to be a bit drabber in color.  At any rate, studying the variety of tanager plumages during the autumn season can be an interesting project!  And, when spring rolls around and the tanagers return from their wintering grounds in Mexico, Central America, and the northern portion of South America, most of the young males will have plumage in a patchwork of red and yellow, as in the photos below.  It takes another year for their yellow feathers to be completely replaced with red. 

Preening immature male Summer Tanager

 

Immature male Summer Tanager

Summer Tanagers feed mainly on insects and fruit, and this is evident from the shape of their bills, which are stouter than those of exclusively insectivorous species, but slimmer than those of seed-eaters.  Actually, most people should probably be thrilled to have tanagers around, since the birds’ favorite insects to consume are bees, wasps, and hornets!  One of my earliest Summer Tanager sightings was of an adult male casually catching paper wasps high in a sweet gum tree in my backyard, and I’ve witnessed countless other tanager and hymenopteran interactions since then.  If there isn’t too much ambient noise, then you can sometimes even hear the *SNAP* of a tanager’s bill as it closes on the bee or wasp.  The tanager will then sometimes vigorously rub its prey against a tree branch before swallowing it whole and, later, regurgitating the tough, indigestible bits of insect exoskeleton.  Yep, hawks and owls aren’t the only birds to produce pellets; most species do.

I have never seen an active Summer Tanager nest—perhaps surprisingly, considering how interested I am in birds’ nesting habits.  However, monitoring a nest if I found one would probably not be too difficult, since tanagers prefer building on branches over open spaces and gaps in the woods.  There would be minimal vegetation in the way!  The usual number of eggs for the species is three to four, which are laid in a cup-shaped nest of grasses and leaves.  Females do the incubating, but both parents feed the young throughout the nestling stage and for at least a few weeks after the fledging.  Because Summer Tanagers are Neotropical migratory birds, developing survival skills during their first summer and autumn is crucial; after all, they don’t get any do-overs during that first grueling and hazardous journey to the wintering grounds.  If they make it back to the breeding grounds in the spring, then they can start to claim nesting territories for themselves, continuing the cycle.

Although summer is nearly over, there are still plenty of opportunities to see Summer Tanagers in their breeding range before they depart around mid-October.  Listen for the calls, watch for the wasp-catching behavior, observe the varied plumage patterns, and just enjoy the presence of our other “redbird.”

Source:

Robinson, W. D. (2020). Summer Tanager (Piranga rubra), version 1.0. In Birds of the World (A. F. Poole, Editor). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bow.sumtan.01

The Stages of Cardinal Life

A couple of years ago, I observed and photo-documented the stages of a Northern Cardinal nest—from construction to the fledging of the young.  This process takes roughly a month, which doesn’t seem like very much time, but the fact of the matter is that young birds aren’t equipped to live on their own right after leaving the nest.  In the case of Northern Cardinals, fledglings continue to be fed by their parents for at least a month as they learn how to function as adults.  They’re not much different from human teenagers, when you think about it.

Although I didn’t find a cardinal nest this year, I have been able to watch “teenager” cardinals as they hang out with their parents.  If the sheer numbers of cardinals are any indication, there were probably at least a couple of successful nesting attempts in the woods near my home this season.  Some of the cardinal parents brought their young to the backyard feeding station, allowing me to see them up close and to study their plumage patterns and behavior.

Juvenile cardinals have dark bills, unlike their parents, which have red or orange-red bills.  The color change is generally complete by winter.  In the photo below, you can see a little bit of orange beginning to come through on the base and margins of the juvenile cardinal’s beak.  Female and male cardinals look very similar in the juvenile stage, but males can have a hint of red on their flanks.  It can be hard to tell, though, and the photo doesn’t provide a lot of strong clues in either direction. 

Juvenile cardinal

This next photo shows a different bird—an immature male.  This cardinal probably came from an earlier brood than the last bird, and its molt into adult plumage has progressed much farther.  Look at the red blotches on the head, back, and flanks. 

Immature male cardinal

The first of the two photos below shows the young male bird from another angle, where you can see all of the red feathers that are coming in on the breast.  The bill has also turned almost completely red.  This fellow has probably been fending for himself for a while now, but he won’t be ready to compete with scrappy, aggressive, adult males, like the one in the second photo, until next year.

Immature male cardinal -- not quite there yet

Adult male cardinal

Although both adult female and juvenile cardinals have reddish tails and flight feathers, adult female cardinals have red crests, as you can see in the first of the two photos below.  In about a year, female cardinals are ready to compete for territories and start nests.  Yes, they compete in much the same way that males do; research has shown that, on breeding territories, female cardinals chase away other females, and male cardinals chase other males.  Females also sing, if somewhat less frequently than males.  Juvenile cardinals might sing softer, unstructured versions of adult songs, as they are still learning.  They will consistently give whistled begging calls whenever they want food from their parents, though!  If you find some juvenile cardinals in the wild, watch for their wing-fluttering behavior and listen for those piping calls.

Adult female cardinal -- note the orange beak

Juvenile cardinals with gray beaks

As cardinals—both the adults and the juveniles/immatures—molt from one plumage to the next, sometimes they wind up looking a bit weird.  One of the most common “oddities” is when a cardinal loses most or all of the feathers on its head.  These cardinals can look as though they have a horrible disease, but, in most cases, they are perfectly normal and will have new feathers in due time.  The cardinal in the foreground of the next photo is an adult female with a bald, gray head. 

Earlier in the month, I routinely saw a female cardinal with a bunch of feathers sticking up on her back.  (This bird is actually the female cardinal in the fifth photograph of the post.)  Try as I might, I never could tell whether this was an injury or simply a scraggly patch from a recent molt.  The cardinal seemed to have no difficulty in foraging, flying, and generally moving around, so I didn’t worry about it, but it was certainly interesting to observe.

Ruffled feathers?

As you can probably tell, the wide variety of plumages that Northern Cardinals display during this season of the year makes it fairly easy—at least, for a brief window of time—to determine their age and to track some of them as individuals.  By next spring, some of this year’s juveniles will hold breeding territories of their own, and the cycle will continue.

Source:

Halkin, S. L. and S. U. Linville (2020). Northern Cardinal (Cardinalis cardinalis), version 1.0. In Birds of the World (A. F. Poole and F. B. Gill, Editors). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bow.norcar.01