Hummingbird Homecoming

 

Hummingbird feeders are busy during spring migration!

Early spring marks the beginning of several natural events, and one of the most welcome is the return of hummingbirds to central Texas.  While the number of hummingbirds migrating north in the spring is only about half of those migrating north in the fall (as the fall migration includes all immature birds that hatched in the summer as well as surviving adults), spring migration for these tiny birds is nonetheless an incredible feat.

Most scientists believe that the lengthening of daylight hours triggers the journey north, and evidence exists that hummingbirds follow a different route in the spring versus the fall.  While they follow the Texas coast south in the fall, presumably to avoid hurricanes in the Gulf of Mexico, in the spring they travel north hundreds of miles non-stop directly over the gulf’s calmer waters. 

Hummingbird feeders, filled with a clear solution (no red dye) of one-part white table sugar to four-parts water, should be placed out in early March.  Records show that the migrating hummers start arriving in our area at that time.  While these migrants can include more northern species that are just passing through, they mainly include the arrival of species that breed in our area, such as the Black-chinned Hummingbird (Archilochus alexandri) and the Ruby-throated Hummingbird (Archilochus colubris).

Black-chinned Hummingbird, male

Measuring a mere three and one-half inches long with a three and three-quarter-inch wing span, the Black-chinned hummingbird weighs only three to three and one-half grams, which is about equivalent to the weight of a dime plus a dollar bill. The male is dull metallic green above, gray below, black on the chin and upper throat, with an iridescent violet lower throat known as a gorget (pronounced gore-jet). The female lacks the characteristic coloring on the chin, upper throat, and lower throat.  Ruby-throated hummingbirds are also only about three and one-half inches long with the adult male having a black upper chin and ruby-red gorget, and they are a more eastern species with Austin being the westernmost border of their range. 

Ruby-throated Hummingbird, male

Like all hummingbirds, nectar serves as a main food source, fueling the tiny bird’s extreme metabolism.  These hummingbirds feed on several species of blooming plants, most notably native penstemons, agaves, salvias, sages, and honeysuckles.  While artificial feeders supplement their diet, they also prey on insects and spiders, particularly during nesting season, which gives them the dietary fat and protein necessary to breed.

The hummingbird’s unique skeletal structure allows them to fly forwards, backwards, sideways, and even on their backs!  This requires a wingbeat frequency of about 50 beats per second, and massive muscles that make up a third of their tiny body weight.  While the males perform an elaborate flight display during courtship, no pair bond is formed between the males and females.  Females build the tiny nest (out of spider webs, mosses, and various plant fibers), incubate the eggs, and raise the young, while the males are feeding and off chasing other females.  This is unusual among birds as a whole, since this class of animals exhibits the greatest amount of monogamy among vertebrates (animals with a backbone or spinal column).

Rufous Hummingbird. male

While most hummingbird species have moved out of our area by late October, be sure to leave a feeder out for stragglers and northern species that may spend the winter in your yard.  The most common overwintering species is the Rufous Hummingbird (Selasphorus rufus), but you can sometimes get a wayward winter visitor such as a Broad-billed Hummingbird (Cynanthus latirostris), a rare species in our area that arrived on our back porch feeder on September 11, 2021 and is still with us!

Broad-billed Hummingbird, male

Blue Beauties

Blue Curls, Phacelia congesta

Spring brings a festival of color to our landscape in the form of wildflowers, mostly in shades of red, yellow, orange, purple, pink, and white.  But the most infrequent color of them all is blue.  There is no true blue pigment in plants, so they don’t have a direct way to produce blue color.  Plants have to perform a sort of trickery to produce blue blooms, using a common plant pigment called anthocyanin.  Plants have evolved to tweak their normally red to purple anthocyanin pigments by naturally modifying pH and then mixing those pigments, and combined with the way natural light reflects, these factors result in the creation of blue flowers.

Dayflower, Commelina erecta

Aside from the well-known bluebonnet, there are other blue beauties in bloom this time of year, including Dayflower (Commelina erecta), Blue Curls (Phacelia congesta), and Texas Bluestar (Amsonia ciliata).  Dayflower is a 3-foot high perennial with soft jointed stems that grow upright only if supported by other plants.  It blooms from May to October, but most frequently in spring or fall. The flowers are about 1 inch across, with two larger showy blue petals and one much smaller white petal.  Lasting only a day, several of these ephemeral blooms occur on one plant, generally one at a time, each opening 3 to 4 days apart.  Often found growing in dry scrub and partly shaded woods, its other common names include Widow’s Tears and White-mouth Dayflower.

Blue Curls, also known as Caterpillars, Fiddleneck, or Spike Phacelia, is a leafy annual or biennial that grows 1 to 3 feet tall in sandy or rocky soil.  Its periwinkle blue, bell-shaped flowers are ¼ inch long and occur in numerous slender, coiled clusters that uncurl as the buds develop, resembling the suckered underside of an octopus tentacle.  Its leaves are soft and deeply cut, often appearing ragged, borne on a brittle stem.  Blooming from March to May, Blue Curls is often found in large colonies in meadows and woodland edges.

Texas Bluestar, Amsonia ciliata

Growing up to 2 feet tall, Texas Bluestar blooms from March to June in dry open woods and on chalky hills.  Its narrow almost needle-like leaves occur singly but close together all long the stem up to the flower cluster.  Every cluster is made up of few to numerous pale blue flowers, each ½ inch long and wide, with a narrow tube opening into 5 petal-like lobes shaped like a star, with a ring of white at the center.  It is also known as Fringed Bluestar, referring to the fringe of small hairs found on the new leaves and plant stems. 

Less than 10 percent of the more than 280,000 species of flowering plants on Earth produce blue flowers.  Interestingly, while blue did not develop as a common color during the process of natural selection, plants that have blue blooms don’t seem to deter beneficial pollinators.  Both birds and insects can widely detect blue wavelengths, and blue flowers are just as capable of producing food as flowers of other colors. 

Early Signs of Spring

Great Purple Hairstreak on Elbowbush (Forestiera pubescens), one
of the earliest plants to bloom, often beginning in February.

A blooming Missouri Violet (Viola missouriensis) is a sure sign
that spring has arrived!

Two-Flower Anemone (Anemone edwardsiana) blooms from February
to April, and prefers the tall grassy banks of moist, shaded canyons.

The yellow blooms of Agarita (Mahonia trifoliolata) appear in
February and March, and eventually form edible red
berries relished by humans and wildlife alike.

In late February and early March, one can often hear flocks
of Sandhill Cranes honking overhead as they make
their way north with the warming weather.

A Juniper Hairstreak sips nectar from the blooms of
an Elbowbush, which is also a favorite plant of native bees.

Texas Redbud (Cercis canadensis L. var. texensis) has clusters
of flowers that appear in early spring before the leaves emerge.

One of the earliest butterflies to appear in spring, Henry's Elfin
utilizes the Texas Redbud as one of its host plants.

Nothing heralds the smell of spring like the heady scent of a
blooming Mexican Plum (Prunus mexicana)!  This small tree is a
must for any pollinator garden.

The Falcate Orangetip is a true springtime butterfly, on the wing
as early as March.