Neither Hummingbird nor Bumblebee

 

Hummingbird or bumblebee?  Neither!

Take a closer look when you see what you think is a small hummingbird hovering about and nectaring on the tubular flowers in your garden.  It just might be a Snowberry Clearwing (Hemaris diffinis), one of our more common hummingbird moths.  

Moths in the genus Hemaris are often generically called hummingbird moths, due to their ability to fly and move just like hummingbirds. They are rather plump moths, and the tip of their abdomen opens a bit like a fan. Many are brown or black with some yellow, so they are also good bumblebee mimics. Several species have clear wings, as they lack as many wing scales as other lepidopterans, and they actually lose the ones they do have shortly after they emerge due to their highly active flight tendencies.  

This adult Snowberry Clearwing just emerged from a winter spent in leaf litter,
still with all the scales on its wings.

The Snowberry Clearwing is about 1.25 to 2 inches in length, with a yellowish thorax above, a black abdomen with a yellowish band near the tip often split in two, and the namesake clear wings. Like other hummingbird moths, they generally fly during the day, but may continue into the evening if they have found a particularly good nectar source. Their proboscis or sucking mouthpart is quite long, so they prefer to sip from tube-shaped flowers. 

An adult Snowberry Clearwing showing its yellow thorax, black abdomen with a
yellow stripe, and signature clear wings.

The adults start flying in March after emerging from the leaf litter beneath their host plant where they spend the winter as a pupa protected by loose silken cocoon.  Females attract males by broadcasting a pheromone from the glands at the tip of the abdomen, and after mating, they lay individual, tiny, round green eggs on the underside of the leaves of the host plant.  In the south, they typically produce more than one generation each summer, flying well into November.

The common name for the Snowberry Clearwing comes from the fact that it was first described in 1836 in the northeast, where it uses Common Snowberry (Symphoricarpos albus) as a host plant, a native plant in the Honeysuckle family that grows in the northern half of North America. In the southern US, the preferred native host plant for this moth is Coral Honeysuckle (Lonicera sempervirens), which can be purchased at most native plant nurseries.  It is a high-climbing, twining vine to 20 feet long, with smooth, paired semi-evergreen leaves and clusters of red, tubular flowers.  In the wild, they also use our native White Bush Honeysuckle (L. albiflora), which is more shrub-like with twining branches that have smooth, paired deciduous leaves and clusters of creamy white tubular flowers.

Coral Honeysuckle

White Bush Honeysuckle

The larva or caterpillars of the Snowberry Clearwing are commonly called hornworms, due to the horn-like projection on their posterior end.  They are up to 2 inches long, blue-green above and yellow-green along the sides, with black spots and a black horn.  Uncommonly, they can also take a brown form with the same black spots and horn.  They match the foliage of their host plants so well that they are often very difficult to find. 

Snowberry Clearwing larva, green form.

Snowberry Clearing larva, brown form.

Nature's Nap Time

Cold winter temperatures cause many animals to rely on different forms of hibernation.

As fall turns to winter, many animals begin to alter their patterns as the days become shorter, temperatures turn colder, and food becomes scarce. Depending on the species and their environment, there are several strategies that different animals can use to overwinter. Current thinking is that these strategies are not necessarily distinctly separate, but rather lie along a single spectrum. 

True hibernation or dormancy is a state of nearly complete reduced activity defined by a lower body temperature and metabolic rate. A loud noise or movement won’t wake an animal in this state.  However, not all animals undergo a true hibernation, especially in warmer climates areas like central Texas.  Native bumblebees are an example of true hibernators in our area, as they seek shelter in a hole in the soil, under leaf litter, or in hollow plant stems.

Native bumblebees are true winter hibernators in Central Texas.

Brumation is another hibernation-like state exhibited by several cold-blooded reptiles and amphibians such as snakes, lizards, turtles, and fish.  This state can last for months and is triggered by colder temperatures and shorter days. These animals will den in rock crevices or dirt burrows, sometimes alone, but often in groups as in the case of garter snakes. While their body temperature, heart rate, and respiratory rates are greatly reduced, some animals in this state may awaken periodically to drink water.

In winter, Black-necked Garter Snakes often den in groups.

This Green Anole came out of brumation on a warmer winter day.

Not as deep as hibernation, topor is a state that can last for several days or weeks. This light hibernation lasts for short periods of time, allowing animals to wake up on warmer winter days. Such is the case for ground squirrel species such as the Rock Squirrel. Some bird species, such as hummingbirds, go into torpor nearly every night to conserve energy, and can even enter a torpid state during colder days.

Rock Squirrels enter a state of torpor during the colder winter months.

While there are different types of hibernation strategies, hibernation states can also be categorized by the factors that induce that state.  Facultative hibernation in animals is caused by environmental conditions such as lack of food, short daylight hours, cold temperatures, or a combination of these stressors. This can induce short or longer periods of topor throughout the colder season. Obligate hibernation applies to animals that hibernate spontaneously every year for long or short periods, regardless of temperature or food supply. 

Most animals build up fat reserves in the fall to survive the colder winter periods in which they are dormant or less active. However, climate change may disrupt these patterns, as drier summers, warmer autumns, and long-standing droughts can lead to lower food production.  This may cause animals to enter hibernation states without the stored calories they need, and emerge early from hibernation hungry for food that is not yet available.  These types of timing mismatches will become more prevalent as our planet warms, disrupting the rhythms of nature’s nap time.

Migration Isn't Just For The Birds

 

Wandering Glider dragonflies do more than wander...

Most people who are interested in nature know that each spring many species of birds migrate north, and each fall they migrate south.  But birds aren’t the only animals that participate in this amazing natural phenomenon, as even some insects (other than the well-known Monarch butterfly) participate in long-distance migrations as well.  While insects are the most species-rich and abundant group of macroscopic organisms on the planet, understanding many aspects of their annual cycles and behavior drastically trails behind the ability to identify and classify them. 

Migration is defined as the cyclical travel of an animal as it returns to its place of departure.  It can be accomplished in one or multiple generations.  Some animals don’t migrate at all, and others move only short distances south or north.  While the guiding factors for navigation are still being discovered, migration is typically triggered by local climate, food availability, seasonality, or reproduction.

Adult Common Green Darner

Interestingly, about nine dragonfly species are known to migrate, including the Common Green Darner (Anax junius), Wandering Glider (Pantala flavescens), as well as some species in the Skimmer family such as meadowhawks and saddlebags. These dragonflies are known to travel up to 1500 miles over the full cycle of their migration, taking three generations.

Adult Wandering Glider

The secrets of dragonfly migration were discovered and confirmed by biologists measuring the chemical makeup of their wings.  In their immature or nymph stage, dragonflies grow their wings while still developing in local water.  Because the stable hydrogen isotope concentration varies in concentration by latitude, biologists can estimate the geographic region where adult dragonflies developed as nymphs.  

The female Common Green Darner (bottom) is held by
the male (top) after mating, when ovipositing in water.

From February to August the first generation emerges in the south and migrates north.  From June to October the second generation emerges in the north and migrates south.  Both of these generations have the ability to undergo rapid development from egg to adult.  But from November to March the third generation emerges in the south and is non-migratory, focusing mainly on producing another first generation for the cycle to start again.  It is this generation that employs a different strategy, developing slowly in late fall, entering diapause or actively induced dormancy over the winter, and emerging in early spring.

Dragonfly migration was not well understood until very recently.  Research published in 2018 detailed the journeys of Common Green Darners by analyzing 852 wing samples from eight different countries and utilizing 21 years of citizen scientist observations to link each specimen to its place of origin and establish its migration history. However, it is important to note that the timing of migration and the development of nymphs are both highly temperature dependent, so continued climate change could lead to fundamental changes in the migration cycles for dragonflies and other migrating insect species. So as you can see, migration isn’t just for the birds!

Furtive Fledglings

 

Mixed woodland of oak and juniper in Central Texas is the only breeding habitat
for the Golden-cheeked Warbler.

As the temperature rises and late spring turns to early summer, many bird species are in the throes of caring for newly hatched nestlings (still in the nest) or fledglings (just out of the nest).  As you hike through our oak-juniper forests in the western part of Austin, you just may run across young families of our endangered bird, the Golden-cheeked Warbler (Setophaga chrysoparia).

Adult Golden-cheeked Warblers arrive at their breeding grounds by mid-March, returning largely to the same areas each year and nesting from April to May. They are socially monogamous, with the males arriving before the females to establish their territory. Courtship behavior, rarely observed, involves the female collecting nesting material as the male sings a soft, twittering version of his song, flicking and spreading his wings and tail and sometimes bringing nesting material to the female. 

A male Golden-cheeked Warbler sings from a juniper to establish his territory.

The female chooses the nest site, often in a branched fork of an Ashe Juniper or Live Oak tree, and the nest is built in 4 days, camouflaged by bark strips from mature juniper trees and secured by spider silk. Females lay 3-4 eggs and for the first 3 days she broods or sits on the eggs continuously, being attended to and fed by the male. The eggs hatch in approximately 12 days, and the nestlings are altricial or born helpless and requiring significant parental care.  

Female Golden-cheeked Warblers typically don't have black throats,
but the ones that do are called 'bearded females'.

However, they leave the nest only 8 or 9 days after hatching, staying in the vicinity of their attendant parents, but usually huddled together and partially hidden in the trees. They continue to be cared for by both parents, who actively search for caterpillars and other insects in the foliage to bring directly to the fledglings.  

A fledgling Golden-cheeked Warbler.

The most obvious way to spot these furtive fledglings is by listening for the family group.  As a parent nears with food in its beak, the fledglings chip rapidly and flutter their wings, begging and hoping to be the one who gets the morsel of food.  They grow quiet once the parent takes off to forage again.  Once they get a bit older, they start to follow their foraging parents begging for food, eventually becoming more confident in their ability to fly and learning to forage for themselves. As they become even more independent, the young join the adults in mixed-species flocks in the woodlands before migration begins in July and early August.

This Golden-cheeked Warbler fledgling caught its own food!

If you hear or see a Golden-cheeked Warbler family foraging and feeding in our mixed woodlands, consider yourself lucky.  Of the nearly 360 bird species that breed in Texas, the Golden-cheeked Warbler is the only one that nests exclusively in Texas, so each one is a native Texan! 

The Real Rocky the Squirrel

 

Telltale signs of a Rock Squirrel Den

The squirrel family includes several different species that are grouped into tree squirrels, ground squirrels, and flying squirrels.  In central Texas, most are familiar with the Eastern Fox Squirrel (Sciurus niger) and the Eastern Gray Squirrel (Sciurus carolinensis), both of which are tree squirrels, meaning their habit is to live mostly among trees. The Southern Flying Squirrel (Glaucomys volans) occurs rarely in the eastern most portion of our area, and is named for the special flaps of skin on the sides of its body which allows for gliding flight.  But it is the Rock Squirrel (Spermophilus variegatus), which generally lives on or in the ground rather than in trees, that is our most notable ground squirrel.

Rock squirrels are stout, moderately bushy-tailed mammals, with mottled grayish-brown upperparts, a more brownish hind back and rump, buffy underparts, and a tail mixed with buff and brown and whitish tips.  The head and upper back are often distinctively blackish, and they have a light-colored ring around each eye. Adults are typically about 18 to 20 inches long, including the tail, and are found from central Texas westward into the Trans-Pecos region of west Texas.

Adult Rock Squirrel

As their common name implies, rock squirrels nearly always inhabit rocky areas such as cliffs, canyon walls, cervices, and rock piles, and even man-made areas like fills along highways and retaining walls.  These areas are where they seek refuge and create their dens.  Although they are typical ground squirrels, they can climb trees nearly as well as tree squirrels, where they can forage for berries and seeds, and they can scale rock walls with ease.  Their diet consists of a variety of plant materials, along with many types of insects.  Unlike many other squirrels, they are fond of flesh and can catch and eat small birds. They can survive long periods without water, some even up to 100 days.

Rock squirrels are facultative hibernators meaning they enter hibernation only when either cold-stressed, food-deprived, or both.   In central Texas they generally hibernate from November to February or March, often coming out to sun during warmer winter days.  Their populations tend to be colonial, each consisting of multiple breeding females and a dominant male.   Home ranges can be fairly large and include several different dens, and the males are thought to be polygamous.  Breeding occurs in March and April with an average litter of 4 young that emerge from the den in late spring.

A litter of 5 young Rock Squirrels

Most active in early morning and late afternoon, rock squirrels are rather shy and difficult to observe at close range. Like other ground squirrels, they are known for their tendency to rise up on their hind legs whenever they need to see over tall vegetation or when they sense nearby danger.  They then curl their front paws flat against their chests and send out a sharp, clear whistle to warn other family members if they sense the presence of predators.  Now you know more about Texas’ very own real-life version of Rocky the Squirrel!

Late Summer Skimmers

The quiet waters of a pond like this make great dragonfly habitat

Dragonflies are conspicuous visitors to various bodies of water, especially in the warmer months of the year.    These visitors include members of the largest family of dragonflies, the Libellulidae, otherwise known as the skimmers. Skimmers can be large and colorful, some with distinctive wing patterns, and are often seen perching on twigs and branches.  In late summer, especially after summer rains, some locally common but not often observed species can be found around newly refilled ponds, including the Gray-waisted Skimmer (Cannaphila insularis), Needham’s Skimmer (Libellula needhami), and Slaty Skimmer (Libellula incesta).  

Found in shady or marshy ponds, typically with tall reeds or cattails, the male Gray-waisted Skimmer has greenish-blue eyes, a white face in front and metallic blue on top, and a dark brown or black thorax divided by several pale stripes.  Its abdomen is pruinose gray on the front half and black on the back half, and its wings are clear with extreme dark only at the tips.  Females and juveniles have a yellow-orange abdomen marked with dark brown or black.  Gray-waisted Skimmers are often found perching in the shade at the tips of vegetation, with their abdomen held nearly parallel to the perch.

Gray-waisted Skimmer, male

The male Needham’s Skimmer has reddish-orange eyes and face, and a thorax than is orange in front and paler or more tannish on the sides. Its abdomen is reddish-orange with a dark dorsal stripe down the length, and its orange wings are somewhat darker along the leading edge.  Females and juveniles have brown eyes and faces, a yellowish-brown thorax, and their abdomens are yellow with a dark stripe running down the middle.  Needham’s Skimmers are typically found perching low on vegetation or overhanging the water’s edge.

Needham's Skimmer, male

Most often seen around marshy forest ponds, the male Slaty Skimmer has dark eyes and a metallic blue or violet face, and both the thorax and abdomen have an overall slaty-blue pruinescence.  The wings are typically clear, but can have a pale bluish stripe along the leading edge.  Females and juveniles have red-over-gray eyes and a pale face, a cream-colored thorax with broad dark shoulder stripes, and a black abdomen with yellowish-orange markings. Females also have more prominent dark wing tips and develop a pale pruinosity at maturity.  Males perch on top of tall grasses and sticks most often in sunlit areas.

Slaty Skimmer, male

Check out your local pond or body of water before the end of September, and you just might be rewarded with a sighting of these less common, late summer skimmers!

Hoppin' Orthoptera

Grasshopper nymphs are often mini versions of the adults

Take a walk through a meadow on a late summer or early fall day, and you’ll no doubt encounter members of the insect order Orthoptera: grasshoppers, crickets, and katydids.  While their Greek name translates to ‘straight wings’, these insects are better known for their jumping ability and powerful hind legs that can propel them to 20 times their body length. 

Abundant, large, colorful, and often noisy, orthopterans are unlike other insects in that they undergo an incomplete or gradual metamorphosis.  Their simple lifecycle consists of an egg, nymph, and adult, where the nymphs look similar to adults, but lack completely developed wings.  Eggs typically hatch in the spring, nymphs develop through the summer, adults mate and reproduce in late summer and fall, with winter passing in the egg stage.  They have three basic body parts: the head, which contains sensory parts such as antennae, eyes, and mouthparts; the thorax, which contains the legs and wings required for movement; and the abdomen, which bears the digestive and reproductive organs.

The use of sound is crucial in courtship, with each species having its own distinct song.  Males attract mates through stridulation, or producing sounds by rubbing the upper and lower wings or the hind leg and wing together creating a vibration that is species-specific.  The auditory organs for orthopterans are not located on their heads, however, but on the abdomen for grasshoppers and the front legs of crickets and katydids.

Differential Grasshopper

Common throughout Texas is the Differential Grasshopper (Melanoplus differentialis), which is brown to olive-green and yellow and up to 1.8 inches long, with black herringbone markings on its legs.  It feeds on both grasses and broadleaf plants, although it prefers the latter, and is often found in areas of lush vegetation. Both nymphs and adults tend to aggregate together, and the adults are found from July to October.

Obscure Bird Grasshopper

Also found thoughout Texas is the Obscure Bird Grasshopper (Schistocerca obscura).  This large grasshopper, to 2.5 inches long, has olive-green forewings and typically a pale yellow-green dorsal stripe from the front of the head to the wing tips. While females can lack this stripe, both sexes have blackish-purple tibia with yellow, black-tipped spines.  This species prefers fields and open woodlands, and can sometimes feed on flowers and shrubs.

Green-striped Grasshopper

The Green-striped Grasshopper (Chortophaga viridifasciata) is found everywhere in Texas except for the southernmost portion of the Trans-Pecos.  Up to 1.5 inches long, it has both a green form (usually females) and a brown form (usually males). Between forms, the main difference is the coloring of the head, thorax, and outer face of the hind femora, with the abdomen always being reddish-brown. This grasshopper prefers wet areas with short grasses on which to feed.    

Narrow-winged Tree Cricket

More often heard than seen, Tree crickets (Oecanthus sp.) are whitish to light green, with long antennae and slender bodies.  In late summer from dusk into the evening hours, the males begin to chirp, with the rate of the chirp correlating to the outside temperature.  If you count how many chirps you hear in 15 seconds and add that to 40, you’ll come surprisingly close to the actual air temperature in degrees Fahrenheit.  

Field Cricket

Field crickets (Gryllus sp.) are dark brown to black, about 1 inch long, live in cool, dark areas, and normally emit high-pitched, continuous calls.  Those that live in caves are dark brown, have well-developed hind legs, and exhibit a hunchbacked appearance.

Fork-tailed Bush Katydid

The antennae of katydids are hair-like and at least as long as the body, superbly represented by the Fork-tailed Bush Katydid (Scudderia furcata).  This all-green katydid is often found in weedy fields, thickets, forest edges, and along roadsides. Up to 2.2 inches long, the first generation matures in late spring and the second in early fall.  Interestingly, the overall size of the adults varies and is directly related to how fast they must mature in order to fully use the growing season to produce the maximum number of generations.

Often, what you can’t identify by sight during the day becomes clear when it sings, calls, buzzes, or chirps at night.  Immerse yourself in the nighttime soundscape, and hear your way to discovery!

Outmaneuvering Mosquitos

Mosquitos can be a nuisance in the hot summer months.

As the temperatures start to increase so do the ads for mosquito-control companies that offer to blanket spray residential landscapes.  While many of these businesses claim that their treatments only kill mosquitos and other pests, in reality the broad-spectrum insecticides they use kill many other species.

Broad-spectrum insecticides are indiscriminate, and along with killing mosquitos, they also kill pollinators and other beneficial insects such as bees, butterflies, moths, caterpillars, dragonflies, damselflies, and lady beetles.  The damage continues further up the food chain, when birds die as their insect food disappears and aquatic animals such as fish die when these chemicals wash off our landscapes and flow into nearby creeks, ponds, rivers, and lakes. Even spraying with essential oils such as peppermint, rosemary, and lemongrass is discouraged, as these can also kill beneficial insects.

Keeping mosquitos at bay can be vital, with many mosquito-borne tropical diseases such as West Nile, Zika, and Dengue fever spreading in range.  However, there are other natural, safer alternatives to using broad-spectrum insecticides.  It starts with understanding that mosquitoes can breed in less than one inch of water, and that the most effective way to reduce their numbers is to target the larvae, not spray adults.  

Moving water discourages female mosquitoes from laying eggs.

Begin by removing any standing water in gutters, bird baths, flower pot saucers, children’s pools, pet bowls, watering cans, and anything else that can hold water. Female mosquitoes avoid laying eggs in moving water, so consider adding a small pump or fountain to a water feature. For standing water that cannot be drained, use a mosquito dunk that contains the natural bacterium Bti (Bacillus thuringiensis israelensis) that kills mosquito larvae as they hatch, and consider adding native mosquitofish (Gambusia species) if the water feature is permanent.  Mosquitos are weak flyers, so even setting up fans reduces their ability to find an individual.

Black-chinned Hummingbirds get protein from eating insects like mosquitoes.

.

Neon Skimmer dragonflies love to prey on mosquitoes.

Most surprising to many, those who garden for wildlife using native plants have fewer mosquito problems than those with non-native turf lawns.  Native plants attract natural mosquito predators such as birds (warblers, wrens, woodpeckers, hummingbirds), dragonflies, damselflies, frogs, turtles, and bats.  Hummingbirds consume hundreds of insects daily in addition to drinking nectar, dragonflies and turtles eat mosquito larvae before they can hatch, frogs specialized sticky tongues nab all kinds of insects, and bats consume millions of insects on the wing.

The sticky tongues of frogs like this Leopard Frog can catch adult mosquitoes.

Red-eared Slider turtles eat mosquito larvae before they hatch.

It is important to note that even if you have a native landscape and don’t spray for mosquitos but your neighbors do, you will still lose pollinators and other beneficial insects.  Recent studies have shown that nearly 3 billion birds have disappeared from North America since 1970 due to loss of their insect prey, and many insect species are rapidly declining or vanishing altogether. 

Make your voice heard by spreading the message that insecticides are significant contributor to wildlife decline, and how we outmaneuver mosquitos in our landscapes truly matters to us all.

Bodacious Borers

Cottonwood Borer

As spring turns into summer in Central Texas, the heat brings out some of our most interesting creatures, most notably the native wood-boring beetles.  This group encompasses many species and families of beetles, all of whom eat wood either in their larval or adult form.  Most often they are found in or around dead or dying trees, as they are vital players in enabling the turnover of weak trees with strong ones, and acting as primary decomposers of wood which allows for the recycling of nutrients back into the soil.

One large family of beetles in the wood-boring group is the longhorn beetles, or Cerambycidae, typically characterized by their extremely long antennae which are often as long or longer than the beetle’s body.  Their family scientific name comes from the mythological Greek shepherd Cerambus, who was turned into a large beetle with horns after an argument with nymphs.  Three of the more noticeable wood-boring longhorn beetles in our area include the Banded Hickory Borer (Knulliana cincta), Cottonwood Borer (Plectrodera scalator), and Texas Bumelia Borer (Plinthocoelium suaveolens plicatum).

Banded Hickory Borer

With a body length of up to 1.4 inches, the Banded Hickory Borer is a fairly slender, typically gray to reddish-brown beetle with a pair of pale marks near the base of the elytra or wing covers that are sometimes absent, and tiny spines at the ends of the elytra.  Eggs are laid by the adults in bark crevices or directly into hardwoods such as oak, pecan, walnut, willow, and hackberry, upon which their larva feed.  In their first season, the larva feed just beneath the bark, then head deeper into the wood as they develop, a cycle which takes two to three years to complete.

Cottonwood Borer

The Cottonwood Borer is an elongate, unmistakably robust beetle with black and white markings that are formed by contrasting areas of white pubescence or fine short hairs on black body parts.  At a body length of up to 1.6 inches, the summer-active adults lay eggs in August and September on cottonwood and willow, where larva bore into the base and overwinter.  After two or three years to reach maturity, they pupate in chambers beneath the bark and emerge as adults in late spring, and are often found feeding on new shoots, leaf petioles (stems), and the bark of their host trees.

Texas Bumelia Borer

One can hardly miss the bright iridescence of the metallic green Texas Bumelia Borer, with its contrasting reddish-orange and black legs. The larva of this species feed on gum bumelia and mulberry, developing in the roots and trunks of these host plants.  With a body length of 1.5 inches, the adults are diurnal and often found on the trunks of their host plants, although they typically feed on flower nectar and are attracted to lights.

Despite their large size, most native wood-boring beetles are not pests.  Instead, they take advantage of dead and dying trees and aid in the natural decomposition process. As you venture out and about this summer, see if you can find some of these bodacious borers!

Ancient Alligators

Texas Alligator Lizard

An ancient and widespread lizard family, Anguidae originated in the Triassic Period, over 100 million years ago.  Today there are 67 species recognized worldwide, with 8 found in North and Central America. Members of a large branch of the snake/lizard evolutionary tree that use their strong jaws rather than tongues to draw food into the mouth, Anguids reserve their hard, slightly forked tongues as chemosensory organs used to search for food, mates, and safe refuge.  

One subfamily within this group is called the alligator lizards, so named due to a vague resemblance to an alligator – a flat, wedge-shaped head, little neck definition, small, thin legs, and scales fairly large and shingled that barely overlap one another. These lizards shed in one piece, much like a snake, turning the old skin inside out as they crawl out of it.  They can also exhibit tail autonomy, the ability to shed their tail as a self-defense mechanism to elude a predator’s grasp and allow escape. While they have the ability to regrow their tail over a period of weeks or months, the new tail is often shorter and distinctly different in appearance from the original tail.

The only species of alligator lizard in Texas is the Texas Alligator Lizard (Gerrhonotus infernalis). Males have wider, more triangular heads than females, but both can grow up to 18 inches long, including their tail. Ground color ranges from light tan to dark brown, sometimes with a reddish cast, with 7 to 10 black and white flecked bands across the body. Newly hatched individuals look entirely different than the adults, with striking copper-colored heads and boldly banded black and cream bodies that resemble centipedes or millipedes.

Generally preferring moist areas of foothills to lowland limestone canyons, staying near springs, creeks, and streams, the Texas Alligator Lizard can even be found in suburban areas near these habitats.  They feed primarily on insects, spiders, and small vertebrates. However, they are secretive in nature, hiding under surface cover such as fallen tree limbs, forest undergrowth, and in rocky crevices.  They can be pugnacious when caught, often thrashing about and able to deliver a painful bite. When threatened by a predator, they may flee to water as they are good swimmers, or perform lateral undulation by folding in their thin limbs and slithering away quickly like a snake.   

Depending on the temperature or season, Texas Alligator Lizards may be active by day or night. In spring they are often arboreal as their tails are prehensile and assist in climbing, mating and feeding in vine tangles and other dense vegetation up to 9 feet off the ground.  Fall is mating season, with males fighting each other for the right to court a female.  Eggs are laid in clutches of 5 to 31 under rocks and in crevices between February and June, with females producing a second clutch if conditions are favorable. Unlike many other reptile species, females will remain with their clutch of eggs for the few months it takes them to incubate.

Texas Alligator Lizards are found throughout a few disjunct localities in the Big Bend region and in much of the Edwards Plateau, and are the largest limbed lizards in Texas. While their secretive nature means they often go undetected, it is a special treat to discover and observe one of these ancient alligators!

A Water Dance of Grebes

Eared Grebe in winter plumage, lacking the characteristic and showy golden ‘ear’ feathers.

Winter is one of the best times to observe waterfowl in central Texas. Several species spend the colder months on our quiet lakes, reservoirs, and ponds, searching for food in the open, unfrozen waters.  One interesting family that can be seen this time of year are the grebes, aquatic diving birds known for their strong swimming, but not often seen on land or in flight.

Grebes are not ducks, although both are considered to be waterfowl.  They lack webbed feet like ducks, and instead have lobed toes.  Their legs attach further back on their bodies than ducks, making it supremely awkward for them to walk on land. Combined with their lobed toes, however, these attributes make them powerful swimmers and divers for their size.  In our area, there are three species of grebe that can be observed, the Pied-billed Grebe (Podilymbus podiceps), the Least Grebe (Tachybaptus dominicus), and the Eared Grebe (Podiceps nigricollis).

Pied-billed Grebe

The Pied-billed Grebe is a small but chunky waterbird 13.5 inches long that is brownish overall with a blocky head, short thick bill, and almost no tail.  During breeding season, its pale bill has a vertical black stripe, which gives it its name as ‘pied’ means having two or more different colors.  These grebes can trap water in their feathers, giving them control over their buoyancy, sinking deeply or exposing as much or as little of their body as they wish. The Pied-billed Grebe is present year-round, but are more abundant from mid-September to mid-May.  They are not gregarious, so they are often solitary or found in very small groups.

Least Grebe

Least Grebes arrive in central Texas in mid-September, but become scarce by early February.  As the smallest grebe in North America at 9.75 inches long, they have golden yellow eyes, a slim dark bill, are purplish gray in summer, and overall gray brown with a whitish throat and paler bill in winter.  Rather uncommon or local, they can sometimes hide by submerging their entire body under water with only their bill visible.  The Least Grebe is light and has large wings relative to its size, so it can take flight from the water more easily than most other grebe species.

Unlike the previous two grebes, the Eared Grebe is the most abundant grebe species in the world, but it is largely a winter resident in Texas, typically appearing by October and disappearing by May.  It is also a small waterbird at 12.5 inches in length with a bright red eye, very thin bill, and overall dusky brown with white.  In their summer range further north and west, they are black with chestnut sides, and sport golden ‘ears’ or wispy feathers that fan out noticeably from their cheeks behind their eyes. Eared Grebes migrate only at night, and their southward migration in the fall is the latest of any bird species in North America.

The collective noun for a group of grebes is a ‘water dance’, which refers to the fact that they have some of the most elaborate courtship displays of all birds.  Often described as ballet-like, these displays can include bowing, feather fluffing, and rising up nearly out of the water, extending their necks and appearing to run across the water’s surface.  Displays vary and can occur between mated pairs or two competing males, suggesting that they have multiple functions.

Get out this winter and scan the open waters for these beautiful little birds.  While they are not particularly common, nor do we normally see them in the height of their breeding plumage, they are still standouts among the typical rafts of ducks that overwinter in our area.