Origins of Name/Taxonomy The genus name, Aruiparus, (pronounced aw-RIP-ay-rus) comes from the Latin terms aurum and parus, which mean gold and titmouse respectfully. The species name (pronounced FLAY-vih-seps) is also derived from the Latin. Flavus means tawny and caput is head. In French, Verdin (pronounced VUR-din) translates to yellowhammer and serves both as a description of its head color and its foraging behavior. For many years, Verdins were classified as related to titmice and chickadees of the Paridae family. But in recent years, due to more advanced DNA research, ornithologists have reclassified Verdin to the family Remizidae. While it does display certain behaviors similar to titmice and chickadees, we now know that its closest relatives are the penduline tits of the Old World (Eurasia and Africa). It is the sole species in its genus and the only North American member of the family. The penduline tits are still considered to be closely related to the parids, because members of the two groups have similar behaviors. Both engage in active, acrobatic foraging in vegetation and hang upside down while feeding. Other common or local names attributed to Verdin include, but are not limited to, bushtit, goldtit, and yellow-headed tit.
Photo by Doris Evans
Physical Description Among the smallest of North American passerines, the adult Verdin is only 4 - 4 ½ inches long – about the length of our common hummingbirds here in the Sonoran Desert. Its tiny size, combined with a tendency to stay hidden in dense desert shrubbery, may account for new birders being unfamiliar with this species – until it is noticed at feeders. Most often seen at hummingbird feeders (it apparently has a sweet tooth) that provide access to Verdin (most nectar feeders won’t allow Verdin to gain access); they are noticed hanging upside down, trying to position themselves to get a sweet sip of nectar. New birders will realize that Verdins have much shorter bills than hummingbirds, they cannot hover, and their physical descriptions differ in other significant ways, too. But due to their extremely small stature, they may be initially confused with hummingbirds.
Verdins are mainly gray in coloration and juveniles are an overall dull gray, with slightly darker gray wings. Adults have yellow heads, faces, and throats which are duller yellow during non-breeding months and brighter yellow in breeding months. Additionally, adults have a small triangular patch of reddish-brown rufous, or burnt cinnamon, at the top of the wing, visible when perched. The use of binoculars will bring this oft-neglected field mark into sharp focus. Adults have a darker gray upper body and wings with paler, almost white, chest and belly. They have fairly short tails. Juveniles are easily distinguished from adults, but adults cannot be visually sexed as they look alike. The bills of Verdin are similar to those of titmice and chickadees, but sharper, more pointed, and longer. Short, darker gray stripes (lores) connect the eyes and bill.
Range and Habitat/Conservation Verdins are not widely distributed as are many more familiar birds. Their range is limited in the United States to the Mexican border states from both sides of the lower Colorado River valley, across southern Arizona and New Mexico, to the southern and western parts of Texas, particularly the Rio Grande River. These birds are common where the habitat best meets their needs in the Chihuahuan and Sonoran deserts. In Mexico, they can be found throughout Baja and, on the mainland, south from the U.S. border to central Mexico. They are frequently seen in lower elevation desert wooded areas alongside washes, in thick desert brush and scrub, and where mesquites thrive. They can be found in suburban and urban areas where desert landscaping is popular with homeowners. Mesquite bosques seem to be their most productive and resource-rich habitat. Look for them, as well, where hackberry, hawthorn, catclaw, screw bean, palo verde, ironwood, acacia, chollas, and other stiff-twigged and thorned trees and shrubs can be found. They can also be found along riparian corridors which have willows, poplars, and other typical riparian vegetation. Verdins are also found in the same habitats as Cactus Wrens, Crissal and Curve-billed Thrashers, and desert horned toads.
Photo by Diane Poleyquiva
Verdins are sparsely distributed within their range but fairly common where appropriate habitat exists. They increased in Arizona over the late 19th century as mesquite brush lands spread but began declining in the late 20th century. Verdin are year-round residents and do not migrate.
Songs and Calls Quite often at backyard bird-feeding stations, a large mixed flock of several species will erupt into a frenzy of loud wingbeats and scatter in all directions at once when a silent predator is stalking or diving into the group. Most of these birds are alert to the alarm call of the Verdin, usually the first species to be aware of an incoming predator and give a loud alarm call that other birds are attuned to. In fact, more often than not, when Verdins are present, it’s their calls that enable other birds to reach safety and avoid an encounter with predators. The call is a piercing, high-pitched tseewf. Its remarkable voice has great depth and carrying power (resonance) for such a small bird, so its alarm call can be easily distinguished above the din of the other birds in the yard.
Its song is a loud whistled tswee, tswee, tswee, tsweet! repeated several times. Its common call is a rapid series of tsit, tsit, tsit, tsit! Its hunting call is a chickadee-like tsee-tu-tu. It has a contact call that sounds like a flat, hard kit or tsik often repeated rapidly, three or four times per second. It also has a high, sharp, slightly nasal kleeu call. Verdin also have a lower-pitched, strong whistle call that sounds like tee too too or tee too tee tee.
Feeding and Foraging Habits In nature, foraging Verdin are usually seen singly, as mated pairs, or in season, as a family group. During cooler winter months, they show little fear of humans, but during spring and summer breeding season, they are secretive and shy, hiding in dense thickets and vegetation. However, at the feeding station, no matter what time of year, they exhibit friendlier and less fearful behavior. There are times when I can reach out to a Verdin on a feeder and only when my finger is about to come into contact does it fly off. While Verdins have been known to eat wild plant seeds in nature, they rarely frequent backyard seed feeders. They have a strong preference for insect meal feeders (particularly the Multi-feeder and the Bugnutter) and nectar feeders. However, most designs of nectar feeders will stymie Verdins. There are only a few nectar feeders that Verdins can easily use. Perky Pet’s Little Beginner and all the Holland Hill glass tube feeders with perches have proven to be the best nectar feeders for Verdin. I have a double- tube Holland Hill window feeder that the Verdins consider their favorite. I once timed their visits over several hours and discovered that they return to that feeder every 10 – 12 minutes, almost as reliably as the hummingbirds that also share the feeder.
Aside from nectar, Verdins are major insectivores. They consume a wide variety of small insects, as well as insect eggs and larvae. They search branches, twigs, buds, and leaves for insect meals. Verdin work dexterously through thorny desert vegetation seeking out their preferred insect foods. They can hang upside down while foraging and use their feet to pull the tips of branches closer for inspection. They may hold larger items, such as large spiders or their cocoons, tightly underfoot while tearing them apart with the bill. They have been observed eating ripe fruit and berries.
Verdins are “nectar-robbers,” like orioles, rather than true pollinators like hummingbirds and bees. They slit the corollas of long tubular flowers to access the nectar, thus bypassing the flower structures designed to deposit pollen on insects and birds. These cuts at the flower bases are often seen on plants such as the Tree Tobacco and other long, deep trumpet-shaped flowers whose nectar would otherwise be inaccessible to Verdins. Afterwards, nectivorsous insects make use of the slits cut by Verdins (and orioles) to rob nectar without pollinating the plants.
Usually found solitary or in small family groups, during the heat of the day in hot weather, Verdins slow their hyper-activity and seek out shaded areas to rest and conserve energy. They sometimes join mixed flocks while foraging.
An interesting fact about these desert-dwelling birds is that, other than being observed drinking nectar at feeders and flowers; they have not been documented drinking fresh water – from any source! They don’t come to birdbaths, puddles, dripping faucets, fountains, or other common fresh water sources. In fact, nests have been discovered more than ten miles from the closest water sources. It is believed that they obtain all their internal moisture needs from the fruits, berries, and insects they consume daily. While they have not been observed using bird baths, it’s not known if they dust bathe.
Photo by Doris Evans
Nesting Verdins construct very strong, sturdy, and durable spherical, globular, or oval nests created entirely of thorny twigs, with an eight-inch diameter. These nests are often constructed of the same materials as the tree that hosts the nest, making it hard to see during breeding season when the vegetation is at its best. The tubular side entrance is concealed with overhanging twigs to keep it hidden from above and to deter would-be predators. While the exterior of the nest is rough, thorny, and includes the use of sticky spider webbing, lichen, and leaves, the interior is smooth and soft and lined with plant down, hair, animal fur, feathers, and other soft materials. Nests are usually located near the center of their territories in familiar desert trees and shrubs. They can be as low as 2 feet or as high as 20 feet above ground, but most are found in or near the center of the vegetation where it is the densest and least visible or accessible.
Both male and female adults construct the breeding nest over the course of about a week’s time. Sometimes the male builds nests at several sites before the female chooses a suitable one. Verdins will appropriate materials from other Verdin nests that are under construction or left over from previous seasons. Nests built early in the season have entrances situated opposite the prevailing winds to avoid the cooler spring air. Nests built later in the breeding season have entrances facing the wind to take advantage of evaporative cooling.
The female feeds the young at the nest for the first five days or so; after that, both parents feed their young. After the young are fledged, the male assumes full care of the family while the female begins a second clutch.
Verdins are unusual in their habit of building roosting nests as well as breeding nests. Roost sites sometimes are old nests used for rearing young or new nests specifically constructed for roosting only. Roost nests typically serve individual young birds but sometimes will accommodate several newly fledged young together. Roost nests are located closest to the center of the tree where branches begin rather than branch ends closer to the perimeter. This provides the fledglings with less visibility and a little extra protection on cold desert nights.
Eggs and Incubation Breeding season for Verdins begins in March and can last until late June or early July. While anywhere from three to six blue-white or green-white eggs are laid, four to five are typical. Verdin eggs are sparingly dotted with reddish brown marks. It is thought that incubation lasts about ten days and, about 21 days after hatching, the fledglings leave the nest. They have left the nest as early as 17 days old and as late as 26 days old. They will, however, return at dark to spend the night sleeping in the nest. Two broods each year per adult female are typical. Babies are hatched altricial – that is pink-skinned, featherless, eyes closed and basically helpless. About 60% of Verdin young develop into adults. The oldest known Verdin lived in the wild until it was five years and seven months.