Friday, June 12, 2015

Serious About Salamanders


Jollyville Plateau Salamander

Humans often wonder why efforts are made to protect biodiversity and save endangered species.  Biodiversity is defined as the variety of life in the world or in a particular habitat or ecosystem, and preserving it provides us with tremendous and vital benefits.  Among others, these benefits include air purification, medicines for better health, fresh water, pollination of crops, carbon sequestration (or storage), and preserving the fertility of the soil. 

Forests purify our air by filtering particulates and regulating the composition of the atmosphere. They act as massive carbon reservoirs, essential to the Earth’s global carbon cycle, and significantly contribute to regulating the global climate. Natural forest soils, with their active microbial and animal populations, have a higher content of total nutrients and biomass, supplying the right nutrients to plants in the right proportions.  Soils and wetlands also act as a filter for water, helping to reduce nitrogen loading, which is a significant form of pollution that occurs as a side effect of development in many parts of the world.  

Roughly 50% of the medicines currently available are derived from natural products.  Of these, at least 120 chemical compounds derived from 90 different plant species are critically important drugs in use around the world today.  Many flowering plants rely on a great variety of animals to pollinate them, including one third of the world’s food crops.  In the U.S., it has been estimated that honeybees alone pollinate approximately $10 billion worth of crops.    

Recently, the U.S. Fish and Wildlife Service protected the Austin Blind Salamander (Eurycea waterlooensis), and the Jollyville Plateau Salamander (Eurycea tonkawae) in addition to a total of 4,451 acres of critical habitat.  These salamanders live no where else in the world, and saving them is also an important step for our region’s long-term water quality and health.  They cannot survive in waterways polluted with pesticides, industrial chemicals, and other toxins, so they are excellent indicators of the health of the environment.

Austin Blind Salamander

The Austin Blind Salamander has external feathery gills, a pronounced extension of the snout, no external eyes, and weakly developed tail fins.  It occurs in and around Barton Springs, which is fed by the Barton Springs segment of the Edwards Aquifer.  The conditions that threaten this species include degradation of its aquatic habitat from pesticides and fertilizers, as well as low flow conditions in the aquifer and the springs.  The Jollyville Plateau Salamander is physically similar to the Austin Blind Salamander, but has generally well-developed eyes, except for some cave-dwelling forms that exhibit eye reduction, head flattening, and loss of color.  Typically, their habitat is spring-fed, and they occur in depths of less than one foot of cool, well-oxygenated water.  While this salamander lives in the Jollyville Plateau and Brushy Creek areas, significant population declines have been observed, likely as a result of degrading water quality from rapid urban development. 

Perhaps one of the most fundamental benefits of saving endangered species is an aesthetic one, as the loss of biodiversity impoverishes our world of natural beauty, both for ourselves and for future generations.  It is yet another good reason for us to be serious about salamanders!  

Tuesday, March 31, 2015

Lovely Lupines


Texas Blubonnets, Lupinus texensis

Bluebonnets are often thought of as the ‘floral trademark of Texas’, akin to the shamrocks of Ireland, the cherry blossoms of Japan, the roses of England, and the tulips of Holland.  Loved for centuries, bluebonnets were described by early explorers as they roamed the vast prairies of Texas, planting them around the Spanish missions by early-day priests, and making them the subject of several Native American folk tales.  Technically known as ‘lupines’ or ‘lupins’, bluebonnets received their present-day common name due to the shape of the flower petals, which resembled the bonnets worn by pioneer women to shield their faces from the sun.

Bluebonnets are part of the legume or bean family, and like other members of this family they offer nitrogen-fixation through their root system’s symbiotic relationship with Rhizobia bacteria.  This gives them the useful ability to grow in poor, disturbed soils, and bring much-needed nitrogen back to these soils as they decompose.  Ironically, bluebonnets are all in the genus Lupinus, which is Latin for ‘wolf-like’, from the original but erroneous belief that these plants ravenously exhausted the soil.

In our area, bluebonnets normally bloom between March and April, but the timing and extent of the blooms depends on the amount of rain received the previous fall and winter.  The flower is purple to blue in color, about half an inch long, with a white spot on the upper petal or banner.  This banner spot acts as a target to attract the bumblebees and honeybees that pollinate the flower. When the pollen is fresh and sticky, the banner spot is white, and is seen by the bees as reflected ultraviolet light and appears to them as a good landing spot.  But as the flower and its pollen age, the banner spot turns yellow and then reddish-magenta, and is ignored by the bees, whose vision cannot see red.  The decline in bee populations has a direct effect on how many seeds a bluebonnet can produce, because bluebonnets cannot self-fertilize.  Each plant has the potential to produce hundreds of seeds, but often only a small number result, due to the recent decline in the number of bee pollinators.

A rare pink Texas Bluebonnet

Infrequently, both white, and more rarely, pink bluebonnets can occur naturally.  In fact, there is a legend associated with how the pink bluebonnet came to be.  Many years ago, in a spring wildflower field near San Antonio, children came across a pink bluebonnet on their way to Lenten devotion at the mission church.  Their grandmother told them the story of Texas, when it was a remote province of Mexico.  After a terrible Mexican dictator overthrew their Constitution, a war broke out between the brave new Texans and the Mexican troops.  The troops eventually overwhelmed the Texans, and much blood was shed and lives lost.  Several years later, the grandmother saw her mother place a pink bluebonnet in a vase by the statue of the Virgin Mary. She said she found it by the river, where “it had once been white, but so much blood had been shed, it had taken a tint of it.”  Interestingly, the only place in the state where the original native pink bluebonnets were found was along the side of a San Antonio road not far from the original mission. 

Big Bend Bluebonnet

Texas has 6 state flowers, more or less, and they are all bluebonnets.  In the spring of 1901, the Texas Legislature selected a state floral emblem after much debate and consternation.  Both the cotton boll and prickly pear cactus were hardy contenders, but the National Society of Colonial Dames of America won the day, and the Sandyland Bluebonnet (Lupinus subcarnosus) was selected and passed into law on March 7th.  And that’s when the bluebonnet war started.  The Sandyland Bluebonnet is a dainty little plant growing in the sandy hills of coastal and southern Texas, and many thought it was the least attractive of all the bluebonnets.  They wanted the Texas Bluebonnet (Lupinus texensis), which was a showier, bolder bloomer.  For the next 70 years, the Legislature was encouraged to correct its oversight, not wanting to get caught in another botanical trap or offend any supporters.  As politicians often do, they solved the problem with clever maneuvering by creating an umbrella clause, and in 1971 added the two species together, plus “any other variety of bluebonnet not heretofore recorded” (including potential species not yet discovered), and lumped them all into one state flower.

Long before the bluebonnet became the Texas state flower, many stories existed about its origins. Some believed it was a gift from the Great Spirit, and that it arrived with rain after a young, orphaned girl sacrificed her precious doll in the hopes of bringing a terrible drought to an end. Whatever you believe, look for these lovely lupines during our central Texas spring!    





Wednesday, March 25, 2015

The Buzz about Bees


There are over 1000 species of bees native to Texas, and this remarkable diversity is attributed to the high number of flowering plant species found in a multitude of habitats throughout the state.  Central Texas is home to at least 185 of these species, many of which inhabit our yards, gardens, and public green spaces.  Bees often get confused with other flying insects, mainly flies, wasps, and sometimes hawk moths.  Flies and wasps, in particular, have similar sizes, colors, and even stripes.  How can you begin to tell the difference?  


In general, bees have longer, thinner antennae, large eyes on the side of the head, four wings (although all four can be hard to see), at least partially fuzzy bodies, and can carry loads of moist pollen on their legs or abdomens.  Flies, on the other hand, have short, thick antennae, large eyes in front of the head, two wings, minute body hairs, and while pollen can stick to their bodies they don’t carry loads.  Finally, wasps have narrow bodies often with a pinched abdomen, very few body hairs, little to no patterns or designs in their exoskeleton, and like flies, don’t carry pollen loads.


Groups of bees that you will commonly see include metallic green bees, honey bees, bumble bees, and carpenter bees. Metallic green bees have an obvious metallic green exoskeleton, but care must be taken to use other methods of identification, as there are also metallic green flies and wasps.  Honey bees buzz as they fly from flower to flower, with a fuzzy thorax and striped abdomen, but while quite common and numerous, are a non-native bee imported from Europe.  


Our biggest native bees are the bumble bee and the carpenter bee.  Bumble bees have a robust body size and shape, mostly black with some yellow or white stripes.  Their entire body is fuzzy, and they fly around in a ‘bumbling’ pattern, making a low buzzing sound.  When landed, they fold their wings neatly over their abdomen.  Carpenter bees are mostly all black, some with a little gold or brown, and the top of their abdomen lacking hairs.  They are fast fliers, sometimes hovering like flies, and make a fairly loud buzz.  Upon landing, they keep their wings splayed apart.




Native bees could fill the important pollinator role currently held by the declining population of non-native European honey bees.  While there is still some debate as to the cause of this decline, there is no debate about the heavy reliance we have on bees pollinating many of our food crops.  Native bees offer an efficient alternative because they are resistant to the mites thought to be harming the honey bees, and because they do not live in collective hives but live singly in nest holes and tunnels, which are not at risk of being overcome by Africanized bees.  Further, native bees and their behavior have evolved so that their actions on a flower actually trigger pollination, so it is possible to find a native bee species that is evolutionally ‘tailored’ to assist a specific crop.  Now that’s something worth buzzing about!

Sunday, March 1, 2015

Spring Heralds


Texas Redbud, Cercis Canadensis var. texensis

Nature has a way of letting us know when spring has arrived in the hill country of central Texas.  In addition to increasing temperatures, the awakening of birds, butterflies, and native plants are among the harbingers that mark the arrival of the season.

More than half of the birds recorded in Texas are migrants.  Returning north in the spring to exploit the more productive temperate regions, they come in search of abundant food supplies, longer daylight hours, and less competition for nesting space. Texans have the advantage of being situated in the path of two flyways or principal routes used by North American birds – the Mississippi Flyway and the Central Flyway – and of the 338 species of North American species listed as Neotropical migrants, 333 are documented for Texas.

Chuck-will's-widows, Caprimulgus carolinensis, lay their eggs on the ground in the spring

Listen for the song of the Chuck-will’s-widow (Caprimulgus carolinensis), which sounds just like its name, rising up from the canyons in the twilight and pre-dawn hours.  Delight in the acrobatic flight of a Scissor-tailed Flycatcher (Tyrannus forficatus), a pearl gray and white bird with salmon-pink underwings and very long outer tail feathers, whose return coincides with the leafing out of the native Honey Mesquite (Prosopis glandulosa var. glandulosa) trees. Marvel at the nest-building skills of the Cliff Swallows (Petrochelidon pyrrhonota), who zoom down to creek beds gathering mud to build colonies of gourd-shaped nests under our bridges and overpasses.  And watch for the Western Kingbird (Tyrannus verticalis), a gray bird with a pale breast and yellow belly, whose raucous calls are heard in between bouts of insect-chasing from perches high in our neighborhood trees.

Scissor-tailed Flycatcher, Tyrannus forficatus

The sweet scents of early-blooming native plants catch our attention and the attention of many pollinating insects.  Some of the most fragrant include the Texas Mountain Laurel (Sophora secundiflora), whose glossy, evergreen leaves form the perfect backdrop for huge clusters of deep purple to whitish flowers, up to ten inches long, that smell like grape Kool-Aid.  Or the less common Mexican Plum (Prunus mexicana), a beautiful small tree identified by its numerous and intensely fragrant white blossoms, which like the pink blossoms of the Mexican Buckeye (Ungnadia speciosa) and the Texas Redbud (Cercis Canadensis var. texensis) and the yellow blossoms of the Elbowbush (Forestiera pubescens), appear on the tree before the leaves begin to emerge.  

Mexican Plum, Prunus mexicana
Elbowbush, Forestiera pubescens

Many of these native plants provide nectar for several species of bees, and are nectar and/or larval food sources for spectacular butterflies such as the Giant Swallowtail (Papilio cresphontes), Two-tailed Swallowtail (Papilio multicaudata), Great Purple Hairstreak (Atlides halesus), Juniper Hairstreak (Callophrys gryneus), Long-tailed Skipper (Urbanus proteus), and Henry’s Elfin (Callophrys henrici).

Henry's Elfin, Callophrys henrici
Juniper Hairstreak, Callophrys gryneus

Wildflowers will soon begin to grace our fields and roadsides, starting with the famous Texas Bluebonnet (Lupinus texensis), intermingled with Indian Paintbrush (Castilleja indivisa), pink Evening Primrose (Oenothera speciosa), Winecup (Callirhoe involucrata), and Indian Blanket or Firewheel (Gaillardia pulchella), to name a few.   These swaths of multi-colored gems not only delight the eye and provide the perfect setting for those upcoming Easter family photos, but they are a key element of the hill country ecosystem, and should be protected and propagated for the visual enjoyment and habitat value they provide all living things.          

Prairie Paintbrush, Castilleja purpurea var lindheimeri

As the weather warms, take the time to go outside and discover for yourself the distinctive essence of a central Texas spring.  As Lyndon Baines Johnson, one of our more famous Texans said, “The beauty of our land is a natural resource.  Its preservation is linked to the inner prosperity of the human spirit.”  Celebrate it!

Sunday, February 1, 2015

Winter Visitors


A congregation of Cedar Waxwings

Like many people from northern climates, there are several bird species that arrive in central Texas to spend the winter!  Three of the most notable are the American robin, the Cedar waxing, and the American kestrel.

American Robin, Turdus migratorius

The largest of our thrushes, the well-known American robin is gray-brown above, with a brick-red breast, white belly, and black-streaked white throat.  Like all thrushes, it is one of our best singers (“cheerily cheer-up cheerio!”), and was named by homesick colonists for the robin that occurs commonly across Europe.  The two are only distantly related, but both have red breasts.  Robins withdraw from the northern portion of their range in winter and migrate southward to seek more abundant food supplies.  They winter throughout Texas, but remain to breed primarily in the northern and eastern portions of the state and locally in the mountains of the west.  On their southern wintering grounds here in central Texas, they congregate in huge flocks, feeding together mostly on berries, and roosting en masse in trees at night.  Earthworms are an important food source during their breeding season, and because they forage for worms largely on suburban lawns, they are vulnerable to pesticide poisoning and can be an important indicator of chemical pollution.

Cedar Waxwing, Bombycilla cedrorum

Gray-brown overall, with a crest on top of the head, black mask edged in white, and yellow tips on its tail feathers, the Cedar waxwing is a beautiful medium-sized songbird.  Gregarious and often flying in flocks, its calls sound like very high-pitched “bzeee” notes.  The waxwing gets its name from the waxy red appendages found in variable numbers on the tips of the secondary wing feathers of most birds.  Waxwings with orange instead of yellow tail tips began appearing in the US in the 1960s as a result of a red pigment picked up by the birds from eating the berries of an introduced (non-native) species of honeysuckle.  One of the few temperate dwelling birds that are “frugivorous” or specializing in eating fruit, waxwings swallow berries whole.  They can survive on fruit alone for months, and unlike many birds that regurgitate seeds from the fruit they eat, waxwings ingest and then defecate fruit seeds.  They are also vulnerable to alcohol intoxication and even death after eating fermented fruit!     

American Kestrel, Falco sparverius

A robin-sized falcon, the American kestrel is a gorgeous bird of prey with a sharp, hooked bill and talon-tipped feet ideal for hunting.  Sometimes called a “sparrow hawk”, the male kestrel is a rust-colored bird with slate blue wings and an unbarred tail while the female, the larger of the two, sports a barred tail and lacks the slate blue on the wings.  Both possess a white face with two black streaks.  Typically, it is the larger female kestrel that arrives on its wintering grounds ahead of the male, which allows her to select preferred habitats, so when the smaller males arrive they must take secondary locations. They utilize open fields and other grassy areas with perches from where they can watch for prey such as flying insects, bats, mice, small birds and reptiles.  They can hover in mid-air while searching for prey and “kite” against the wind, flying at an appropriate speed facing the wind so they can stay in place.

As you enjoy a brisk winter walk in the neighborhood and surrounding areas, keep an eye out for these common but attractive “winter Texans”!  

Friday, December 5, 2014

Merry Mistletoe




From the earliest times mistletoe has been considered one of the most magical, mysterious, and sacred plants found in European folklore.  Originally used to bestow life and fertility, as a protection from poison, and as an aphrodisiac, in medieval times branches of mistletoe were hung from the ceiling to ward off evil spirits. With the process of immigration and settlement of North America, traditions associated with the European plant were transferred to the New World and evolved into a folklore all its own.


In Central Texas, two species of mistletoe are native, the Christmas Mistletoe (Phoradendron tomentosum) and Oak Mistletoe (Phoradendron leucarpum).  The genus comes from the Greek ‘phor’ which means thief and ‘dendron’ which means tree, as both species are semiparasites that steal water and nutrients from their host trees.  Christmas mistletoe has small, elliptical evergreen leaves and smooth green stems covered by short hairs, with tiny green flowers on the male plant and shiny white berries on the female plant. It is widely used in the United States as a Christmas decoration, and is especially common growing on Sugar Hackberry, Cedar Elm, and Honey Mesquite trees in Texas, Louisiana, and Oklahoma.


Native north to New York State, south to Florida, and west to New Mexico, Oak Mistletoe is another common mistletoe hung at Christmastime.  It is a larval host plant for the Great Purple Hairstreak butterfly, and while similar in appearance to Christmas Mistletoe, its berries are covered with a sticky substance poisonous to humans but relished by winter resident birds such as Cedar Waxwings, Eastern Bluebirds, and American Robins.  These birds eat the berries and spread the seeds through their droppings and by wiping their beaks on tree branches, both of which may cause a new plant to take hold and become established.

Great Purple Hairstreak

While ancient folklore has attributed a wide range of mystical abilities to mistletoe, none is more fascinating than the myth of Frigga, the Norse Mother Goddess worshiped by pre-Christian people of northern Europe, and how mistletoe became her sacred plant.  She was believed to be the mother of Balder, the God of the Summer Sun, who had a dream of death.  Alarmed by this dream, Frigga went to all the elements, plants, and animals to seek a promise that no harm would come to her son.  Balder was thought to be safe from harm by anything on or under the Earth.  

But Balder’s enemy, Loki, was the God of Evil, and he knew of the one plant that Frigga overlooked.  It was the lowly mistletoe, which grew neither on nor under the Earth itself, but on the branches of oaks and other trees.  Loki made an arrow tip with the mistletoe, and gave it to the Hoder, the blind God of Winter, who used it to strike Balder dead.  The sky paled and everything wept for the Sun God, who was restored by Frigga after working with the elements for three days. The tears she shed for her son were said to be the pearly white berries of the mistletoe, and in her joy at his resurrection she kissed everyone who passed beneath the tree on which it grew.  

Thus began the custom that whomever should stand beneath the humble mistletoe will come to no harm, but receive only a kiss as a token of love.  Merry mistletoe to you and yours!



Thursday, November 27, 2014

Shadow Tails

Fox Squirrel, Sciurus niger


The word ‘squirrel’ comes from the Greek ‘sciourus’, meaning ‘shadow tail’, and refers to the bushy appendage possessed by most all squirrel species.  They are members of the rodent family, and Texas is home to 10 species of squirrels with 4 of them common in the Austin area.

Along with their bushy tails, squirrels are generally slender animals with large eyes and soft fur. Their front limbs are shorter than their hind limbs, with 4 or 5 toes on each foot.  Their front feet include a usually underdeveloped thumb, and all toes have sharp claws for climbing trees and quickly clamoring over uneven terrain. Squirrels are strongly vegetarian, and feed mostly on a wide variety of seeds, nuts, fruits, buds, bark, and leaves.  Their vision is sharp and they have ‘vibrissae’ or specialized hairs on their head and limbs, which afford them an excellent sense of touch.   

The most common tree squirrels in Central Texas are the Eastern Fox Squirrel (Sciurus niger) and the Eastern Gray Squirrel (Sciurus carolinensis). A large squirrel with rusty or reddish underparts and grayish or brownish upperparts, the Fox Squirrel prefers open woodlands of mixed trees and riparian areas along rivers and streams, and makes its dens in hollow trees or nests made of leaves.  Their diet is largely made up of acorns which are buried in winter and relocated through their keen sense of smell. Mating occurs in January/February, and again in May/June, with offspring born in March and July.  

The Gray Squirrel is a medium-sized squirrel with grayish upperparts with white-tipped hairs, white underparts, and a white spot at the base of its ears in winter.  Gray Squirrels live in dense live oak stands and bottomland areas, with the Austin area in the westernmost part of their range.  There are usually two openings to their nests, which are otherwise similar to the Fox Squirrel, as is their diet and breeding cycle.  Destruction of bottomland habitat from logging, overgrazing by livestock, and development are the main reasons why gray squirrels are only locally common, and declining in many areas.      

Rock Squirrel, Spermophilus variegatus

Our most frequently seen ground squirrels include the Rock Squirrel (Spermophilus variegatus) and the Mexican Ground Squirrel (Spermophilus mexicanus).  A rather large, stout squirrel with a blackish head and upper back and a mottled grayish-brown rump and tail, the Rock Squirrel is nearly always found in rocky canyons, cliffs, and rock piles, where they make their dens.  While they can climb trees, they prefer to be ground dwellers, where they forage for acorns, nuts, insects, and berries.  In Central Texas, these squirrels hibernate beginning in November, and emerge in late February or March to begin breeding.

Mexican Ground Squirrel, Spermophilus mexicanus

The western edge of Austin is the easternmost range for the Mexican Ground Squirrel, a rather small squirrel with about nine rows of squarish white spots on its back and a moderately bushy tail. They prefer brushy or grassy areas, including mowed lawns and overgrazed pastures and live in burrows dug into the soil.  They eat chiefly green vegetation and insects, but are one of the few squirrel species that will eat meat.  Breeding begins in late March or early April, with a brood chamber built into a side tunnel in the deepest part of their burrow. 

Anyone who has seen a squirrel running along a tree limb or across an open road with its bushy tail undulating and waving behind it, or spotted a squirrel sitting with its tail curled over its back while it eats or surveys its surroundings, can appreciate why their name means shadow tail!