Hidden Wonders in the Forests of Northeast Texas

IMG_4141

Rich Hardwood Forest

Target Species: 

Tapertip Trillium (Trillium viridescens)

Downy Yellow Violet (Viola pubescens)

It’s been some time since I’ve posted about one of my “Biodiversity Targets”, those species that I included on my 2017 list of biodiversity goals.  At the end of 2017, I had only tracked down around half of the species on that list, but along the way I amassed a wealth of incredible observations, adventures, and experienced more of our states biodiversity than I ever could have imagined.  So I decided that instead of creating a new list or adding to the existing list, I would work over the next couple of years to finish the list I made at the start of 2017; a list that was a bit more ambitious than I had anticipated.

In early April 2018 my pursuit of these species would take me to the far northeast corner of Texas, near the Oklahoma border in search of two species that I have long wanted to see in the state.  Joining me in this quest was my friend Scott Wahlberg.  We set out early, in the gray of a perfect spring morning.

The counties of far northeast Texas feature a mingling of habitats typical of both the Post Oak Savannah and Pineywoods.  Some communities, like the rich hardwood forests of the Sulphur River and Red River and their tributaries are unique to this part of Texas, and more similar to the forests of the Ouachita Mountains of Oklahoma and Arkansas than they are to those of the heart of the Pineywoods in Deep East Texas.  Here a sweet of species reach the southwestern limit of their range.  Among these are several species that are either absent from, or are very scarce elsewhere in the Pineywoods.  Examples of these include trees like Silver Maple (Acer saccharinum), Black Oak (Quercus velutina), Shingle Oak (Quercus imbricaria), and Nutmeg Hickory (Carya myristiciformis).  Examples also include woodlands forbs such as Fire Pink (Silene virginica), Rue Anemone (Thalictrum thalictroides), Downy Yellow Violet (Viola pubescens), Tapertip Trillium (Trillium viridescens), and more.

The latter two were the focus of this trip.  In Texas, Trillium viridescens occurs in rich hardwood forests on steep river bluffs and in the damp alluvium of  riparian woodlands.  Here we found it growing among other interesting woodland forbs like Mayapple (Podophyllum peltatum), Veiny Pea (Lathyrus venosus), Wild Hyacinth (Camassia scilloides), and White Trout Lily (Erythronium albidum).

Trillium viridescens is a species of the central United States, primarily occurring in the Ozark Plateau, and the Boston and Ouachita Mountains. It barely enters Texas in northeastern portion of the state. The plants in the northern portions of its range generally have petals that grade from purple at the base to bright greenish yellow at the tips. Most Texas individuals, however, tend to be solid maroon to greenish purple.

 

IMG_3723

Tapertip Trillium

The sessile-flowered trilliums can be a tricky group. In Texas, three species, T. gracile, T. ludovicianum, and T. viridescens are superficially similar in many ways, however when I first saw T. viridescens in the field it was immediately clear that this species was obviously different from the other two. The T. viridescens plants we observed were much larger and more robust than any T. gracile or T. ludovicianum I had ever seen. Their faintly mottled, broadly ovate leaves were much different than the state’s other trillium species, which have narrower, more heavily mottled leaves. The petals were also much larger. There are other characteristics that can be used to differentiate T. viridescens from the other two species such as a scabrous vs glabrous scape and a number of differences in flower morphology.

Seeing Trillium viridescens in the field certainly left a lasting impression.   It was a special moment for me, as it was the last of our state’s five species of trillium that I had left to see.  Like all of our other trillium species, T. viridescens is at risk, and is likely declining from a number of factors such as climate change and land use conversion.

Viola pubescens another characteristically eastern species that barely enters Texas in the far northeastern part of the state.  It is a yellow-flowered violet that occurs through most also occurs in parts of central United States as far west as the Black Hills of western South Dakota and eastern Wyoming.  While I have seen and photographed this species in the southern Appalachians, I had long wanted to see it in Texas.

On that fine spring day, we found it in a mature riparian forest along a small order stream.  Shaded by an overstory of Silver Maple, Red Maple, Shumard Oak and Sweegtum,  we found it growing alongside a variety of other woodland herb including Podophyllum peltatum, Packera glabella, Packera obovata, Viola sororia, and Erythronium albidum.

IMG_3991

Downy Yellow Violet

IMG_4090

Downy Yellow Violet

While exploring the backgrounds of northeast Texas we spotted several large clumps of Eastern Bluestar (Amsonia tabernaemontana) growing in a remnant prairie.  Scott and I stopped a moment to photograph them, and discussed what the area must have looked like before the hand of man left it forever changed.  We also pondered the possibility that prairie species like the Southern Crawfish Frog might just still hang on here.  Though I haven’t spent much time in this part of the state, I quickly gained an appreciation of just how diverse it really is.

IMG_3935

While most of northeast Texas remains rural and relatively undeveloped, there is little public land, and most of these populations are on private land and vulnerable. There is still hope, however.   Through conservation efforts with and by private landowners there is hope that these lovely members of our flora remains for future generations to enjoy.

The Biodiversity of the Rio Grande Valley Part 4: The Old Man of the Thornscrub

IMG_2515a

Our last day in the Rio Grande Valley was a memorable one.  Carolina, Erin, James, and I spent the morning admiring wintering waterfowl in a shallow Resaca.  During the heat of the afternoon we found ourselves among Lady Fingers and other spined succulents.  In the evening we took a relaxing stroll to see what sort of wildlife might emerge from the dense thornscrub.

There were multiple times during the trip when the conversation between James and I turned to the Texas Tortoise (Gopherus berlandieri).  This iconic South Texas species was high on both of our lists, but thus far the lumbering reptile had evaded us.  But as the sun sank low on our final day, there it was, meandering along a line of brush foraging on just about anything it could fit in its mouth.

IMG_2309

The Texas Tortoise occurs in southern Texas and northeastern Mexico.  Here it can be found in a variety of habitats including desert scrub, Tamaulipan Thornscrub, and subtropical forests, grasslands and scrublands.  They feed on a variety of foods, though seem to prefer soft vegetative matter.  They are famous for gorging themselves on prickly pears.  Though they remain common in many areas, they are listed as Threatened by the State of Texas and are protected accordingly.  They face threats from habitat loss and collection for the pet trade.

IMG_2217

We spent close to an hour watching the antics of our states only “true” tortoise.  Armed with super telephoto lenses, we were able to observe the ancient reptile from a distance, and its behavior didn’t seem altered by our presence.  At one point it managed to get a large branch stuck on its gular projection, and spent several minutes dragging it along until it finally was able to free itself.  It then continued foraging until finally disappearing into dense grass under a canopy of mesquite.  This special encounter was the perfect ending to an incredible trip with great company.

The Biodiversity of the Rio Grande Valley Part 3: Las Estrellas del Sur

IMG_0130

It was of the utmost importance that we keep our eyes firmly fixed on the ground – scanning among the stones and parched earth.  Important, because we were in the realm of the Star Cactus (Astrophytum asterias), a very rare, Federally Endangered cactus of the Tamaulipan Thornscrub.  The plants themselves are often flush with the ground, look like little more than some stone or anomaly in the soil.  Their flowers, however, announce their presence to the world in spectacular fashion.  Carolina and I had looked for the Star Cactus in 2017 during a trip with my family.  While we found several plants, we did not have the good fortune to find them in bloom.  This year, however, would be different.

This year we were visiting with our good friends James and Erin Childress.  Having developed a search image during our previous trip, I began noticing a few plants scattered about.  My attention was soon diverted, however, when James and I spotted the brilliant magenta blooms of a group of Fitch’s Hedgehog Cactus.  It was in that moment, as we admired a very different cactus, that Carolina called out that she had found one in flower.  Barely able to contain my excitement, I rushed to her.  It soon become evident that we had timed this visit perfectly, as the floor of the Tamaulipan Thornscrub before me was decorated with dozens of bright yellow and orange blooms.

IMG_0061

Though few known populations exist, where it does occur the Star Cactus can be quite abundant.  Today most of the state’s populations are protected and some are thriving.  We would be telling a very different story, however, if it weren’t for The Nature Conservancy in Texas.  Through the acquisition of land and partnerships with private landowners, The Nature Conservancy has ensured that Astrophytum asterias will not disappear from our state’s diverse flora.  In all, the Nature Conservancy through their Las Estrellas Conservation Cooperative has been able to protect over 2,500 acres of Star Cactus habitat, providing safe refuge for thousands of individuals.

Though it is promising, these successes do not mean that the Star Cactus does not still face threats to its existence.  While speaking with Sonia Najera, Grasslands Program Manager of the Nature Conservancy in Texas, she informed me that continued development adjacent to protected land is threatening A. asterias populations that have no protection.  A. asterias is also under threat from poachers who may collect plants for its popularity in cultivation, and for its resemblance to Peyote, which is extensively collected for its psychoactive properties.

IMG_9978

Despite the many threats that they face, I am optimistic for the future of the Star Cactus in Texas, thanks in large part to the Nature Conservancy and dedicated professionals like Sonia.

The day we spent among Las Estrellas in bloom was really the experience of a lifetime.  We observed and photographed so many spectacular plants in bloom that it was nearly impossible trying to narrow them down to decide what to post.  Below is a small selection of favorites from an unforgettable day in the field.

IMG_0295

IMG_0401

IMG_0689

IMG_0708

IMG_0531

The Biodiversity of the Rio Grande Valley Part 2: The Cacti

IMG_7947

Peyote

Spring in the Tamaulipan Thornscrub is a beautiful, albeit deceiving thing.  When the chaparro, huisachillo, and guayacan bloom above a carpet of wildflowers, its easy to forget just what a harsh, unforgiving land this can be.  I was bleeding through my jeans when I sat a moment to rest in the shade of a mesquite tree.  I don’t think that Carolina, James, or Erin had fared much better.  Despite being early March, it was pushing 90 degrees, and the sun was beating down.  After taking a long draw from my water bottle, I got up and continued my search.  I winced as I pushed through the allthorn, and felt the tasajillo spines pierce my skin.  It’s safe to say at that point my spirits weren’t at their highest.  But then I heard the voice of my wife as she called out, “I found one, with a flower!”  In that moment, pain seemed like an insignificant consideration as I pushed through the tangle of thorns that lay between me and my succulent quarry.  I saw Carolina squatting down looking at the base of a large shrub.  There, under the shade and protection of a condalia I could see the iconic Peyote in bloom.

Despite being very un-cactus like, the Peyote may be the famous of all cacti.  Once fairly common in parts of south and west Texas, decades of over-harvest, poaching, and habitat loss of significantly reduced the populations to the point that today they are a rare sight among the thornscrub.  The reason that it has been so persecuted is the psychoactive compound mescaline contained within its flesh.

In fact, Peyote is one of the most well known psychoactive plants.  It has been utilized for centuries by native peoples for both its medicinal and hallucinogenic effects. Today Peyote is a controlled substance in the United States due to its use as a recreational drug. It is, however, legal for many native tribes to harvest and consume for ritualistic purposes.  And though it may be illegal to harvest or possess, poachers continue to devastate Peyote populations to sell them on the black market.

In the United States Peyote is known only from extreme southern and western Texas. Here it occurs in desert scrub and arid brushland, typically growing beneath dense shrubs. It is one of three spineless cacti in Texas. We were lucky enough to observe some in bloom on an extensive private ranch in the Tamaulipan Thornscrub of South Texas, with the help of our dear friends Toby Hibbits and Connor Adams.

IMG_7834

Peyote

In our pursuit of Peyote we observed several other species growing beneath the shelter of their nurse plants.  We seemed to catch the Heyder’s Pincushion Cactus (Mammillaria heyderi) in full bloom.  This small cactus grows low to the ground, and like many species with this growth habit, is very difficult to spot when not in bloom.  In the early spring a single plant may put on a dozen or more flowers, generally organized in a ring along the top of the cactus.  It occurs from Mexico through south and central Texas west across eastern and southern New Mexico into southern Arizona.

IMG_7849

Heyder’s Pincushion Cactus

IMG_7912

Heyder’s Pincushion Cactus

While the Heyder’s Pincushion Cactus may be difficult to spot when not in bloom, the Hair-covered Cactus (Mammillaria prolifera) is difficult to spot even when in flower.  This species is tiny, with individual stems not much larger than an egg, though they may occasionally form large clumps.  The Hair-covered Cactus is known in the United States only from Texas, where it occurs in only a handful of counties in southern and south-central Texas, most of them along the Rio Grande.

IMG_1960

Hair-covered Cactus

Though it is superficially similar to the Mammillaria prolifera, the Runyon’s Pincushion Cactus (Coryphantha pottsiana) is easily differentiate when in flower.  Like many species of cactus, the taxonomy for Coryphantha pottsiana is a bit cloudy.  It has variably been known as Coryphantha robertii, Mammillaria robertii, Mammillaria bella, Escobaria bella, Escobaria runyonii, and Escobaria emskoetteriana.  Some authorities still use the latter, though Coryphantha pottsiana seems to be more widely accepted.  The Runyon’s Pincushion Cactus is known from northern Mexico and a few Texas Counties along the Rio Grande, where it is generally uncommon.

IMG_7803

Runyon’s Pincushion Cactus

While the previous cacti are generally small, the Horse Crippler (Echinocactus texensis) can reach much larger proportions.  While most seem to be about the size of a basketball, we saw some that were easily 3 or 4 times as large.  They tend to occur in looser soil including sandy alluvium.  They are also frequently found growing in the open, away from nurse plants, though its likely that many plants get their start in the less hostile microclimate of a nurse plant.  Their impressive spines seem to be an effective deterrent against mammalian predators.

IMG_0687

Horse Crippler

IMG_0356

Horse Crippler

Among the most beautiful of all cacti are the hedgehog cacti of the genus Echinocereus, a few of which are endemic to the Tamaulipan Thornscrub of South Texas and northern Mexico.  This year our trip coincided with the peak bloom of Echinocereus fitchii, the Fitch’s Hedgehog Cactus.  Though they are generally hard to find, in the right habitat they can be abundant, and we saw dozens, blazing the thornscrub with their pink blooms.  Like Coryphantha pottsiana and so many other cactus taxa, the taxonomy of Echinocereus fitchii is murky at best.  It is considered by many to be a subspecies of the more broadly distributed Echinocereus reichenbachii.  For anyone interested in the topic I strongly recommend reading “A hard-to-manage taxon: The Black Lace Cactus (Echinocereus fitchii ssp. albertii)“.  Though it discusses the Fitch’s Hedgehog Cactus’s Federally Endangered cousin, it includes a good discussion on the taxonomy of E. fitchii and E. reichenbachii, including characteristics used to distinguish the two.

IMG_1214

Fitch’s Hedgehog Cactus

IMG_9920

Fitch’s Hedgehog Cactus

In my opinion, the Lady Finger Cactus (Echinocereus pentalophus) is perhaps the most spectacular cactus native to the United States.  Confined to northern Mexico and extreme southern Texas, they can form huge mats under the shade of mesquite and other trees and large shrubs.  They have even been found growing upon protected ridges adjacent to the Laguna Madre.  Their bright blooms shine neon pink under the midday sun.

IMG_2006

Lady Finger Cactus

IMG_1971

Lady Finger Cactus

The bizarre Pencil Cactus (Echinocereus pentalophus) seems less a cactus and more a tangle of dried branches resting at the base of some thorny shrub.  That is, until it’s giant pink blooms open in the early spring and betray its presence to the world.  Unlike most other members of its genus, the Pencil Cactus produces a massive tuberous roots that aid in water storage.

IMG_1274

Pencil Cactus

The highlight our South Texas cactus hunt, however, was finding the Federally Endangered Star Cactus (Astrophytum asterias) in peak bloom, an experience which I will share in my next blog post.

IMG_0644

Star Cactus

The Biodiversity of the Rio Grande Valley Part 1: The Birds

IMG_8914

Altamira Oriole

At first they appeared as flashes of brilliance – blurs of orange, blue, and green darting through the drab brush country.  It was when we sat still and silent that they revealed themselves to us.  A spectacular cast of avian characters emerged from the dense vegetation.  All around us Green Jays croaked and bobbed.  Plain Chachalacas switched between the earth and low hanging branches.  Only occasionally would an Altamira Oriole appear, descending from the tree tops for a brief moment, it’s bright orange plumage demanding our attention.  The trill of a Golden-fronted Woodpecker broke our concentration, competing with the Great Kiskadee for the loudest call in the thornscrub.

***

The Rio Grande Valley of Texas attracts birders from around the world.  A suite of characteristically Latin American species reach the northern limit of their range here.  This subtropical paradise is a naturalist’s playground.  Ecologically speaking, it shares more in common with Mexico than the rest of the Lonestar State.  When Carolina and I began discussing our South Texas vacation with our close friends James and Erin, birds were certainly one of the main targets that we planned the trip around.

Followers of my blog may remember previous posts where I talked about borrowing James’s 600mm lens for bird photography.  Fortunately another of my generous friends (and one of the finest photographers and naturalists that I know), Seth Patterson, offered to lend me his 500mm lens and teleconverters for the trip.  Though he is an excellent bird photographer, recently Seth is more focused on contributing to the “Meet Your Neighbours” project.  Armed with this new gear, James and I would be able to pursue our photographic targets at the same time, and wouldn’t have to worry about missing a shot.

This post contains some of the avian highlights of our trip, which spanned the diverse Lower Rio Grande Valley, from barrier islands and salt marshes, through ancient palm forests into the unforgiving Tamaulipan Thornscrub.

***

While there are many South Texas species on the top of birders’ wish lists, perhaps the most famous is the Green Jay (Cyanocorax yncas).  They range from southern Texas through Mexico into northern South America.  Intelligent, inquisitive birds, they are a common sight in the brush country.

IMG_8885

Green Jay

IMG_8876

Green Jay

The Altamira Oriole (Icterus gularis) is the largest “true” oriole.  It takes these striking birds two years to attain their adult plumage, with first year birds being generally duller and lacking the bold black back and wings.  Altamira Orioles build pendant nests, which hang from tree branches.

IMG_8801

Altamira Oriole Adult

IMG_8316

First Year Altamira Oriole

Smaller and less commonly encountered than the Altamira Oriole is the Audubon’s Oriole (Icterus graduacauda).  They too barely enter the United States in southern Texas.  The Audubon’s Oriole is poorly understood, with few data on their natural history.  What little data are available indicate that they may be on the decline, likely due to a combination of habitat loss and nest parasitism by increasing populations of Brown-headed Cowbirds.

IMG_0943

Audubon’s Oriole

Another species that South Texas visitors get excited about is the Great Kiskadee (Pitangus sulphuratus)  This boisterous flycatcher makes its home in resacas and riparian corridors.  I’ve been fortunate enough to observe this bird in South Texas, Costa Rica, and northern Argentina.  It certainly has one of the broadest ranges of any New World songbird.  Interestingly, both the English and Spanish names for this bird are onomatopoeas.  Kisk-a-DEE in English, and Bent-e-VEO in Spanish.  In Argentina it was locally known as “bicho feo” (ugly critter), both because this phrase also sounds like its call, and because its obnoxious vocalizations were enough to drive local communities sharing the Kiskadee’s territory crazy.

IMG_9091

Great Kiskadee

While enjoying an intimate view of the valley’s avifauna from the comfort of a bird blind, we witnessed an incredible moment.  The blind was especially productive, with several Green Jays, White-tipped Doves, Plain Chachalacas, Red-winged Blackbirds, and Northern Cardinals.  The occassional Altamira Oriole, Great Kiskadee, and Lincoln’s Sparrow would appear.  In an instant all of the birds scattered.  We could hear their wings cut through the still air as they vanished in a hurry.  The Plain Chachalacas (Ortalis vetula) retreated to some higher branches and began chattering furiously, sharply focused on the brush below.  It was at that moment that we noticed a series of small black blotches moving through the vegetation: the spotted pelage of a Bobcat as it slinked away, unsuccessful in its hunt.

IMG_8400

Plain Chachalaca vocalizing at a Bobcat

The Plain Chachalaca is a large chicken-like bird that skulks in the understory and forest floor.  They are social birds, generally found in small groups as they forage for fruits, seeds, and similar food sources.  Like the kiskadee, they are named for their raucous call.

IMG_8453

Plain Chachalaca

The White-tipped Dove (Leptotila verreauxi) also barely enters the United States in South Texas.  Though they are most frequently observed foraging on the ground in the shade of the dense underbrush, they would occasionally perch on low-hanging limbs.

IMG_8533

White-tipped Dove

Ranging deeper into the United States than the previously mentioned species, the Black-crested Titmouse (Baeolophus atricristatus) none-the-less, is one of the more range-restricted species that we observed during our trip.  It occurs from central Mexico through central and western Texas to extreme southwestern Oklahoma.

IMG_9216a

Black-crested Titmouse

The Ladder-backed Woodpecker (Picoides scalaris) is much more widespread, occurring throughout much of Central America and the southwestern United States.  Pictured below is a male, identifiable by its red crown.

IMG_1140

Ladder-backed Woodpecker

Travelling west into western Hidalgo and Starr Counties, the landscape begins to transition from forested brushland to a mix of thornscrub and desert scrub.  Here we were serenaded by Cactus Wrens (Campylorhynchus brunneicapillus) as we looked for the succulent plants that lend this large wren its name.  Erin spotted one particularly cooperative individual that sat atop the developing buds of a prickly pear and sang for several minutes.

IMG_9629

Cactus Wren

The ubiquitous Northern Cardinal (Cardinalis cardinalis) is ever-present in the valley.  I remember on a previous trip, 10 years ago or more with my family, a couple from western Canada excitedly proclaimed that they had just seen one of the “red jays”.  It was one of the birds they were most excited to see during their trip.  It’s easy to take the common birds for granted, but the Northern Cardinal really is a beautiful species.  The generally duller female has a subtle beauty that makes for a fine image.

IMG_8613

Northern Cardinal

Resacas are shallow ponds and wetlands that dot the landscape of the Lower Rio Grande Valley, most of which have formed in old oxbow scars of the Rio Grande.  The term “resaca” apparently originated from a corruption of rio seco, Spanish for “dry river”.  It also means hangover (at least in Argentina).  These Resacas are home to a variety of interesting bird species.  Green and Ringed Kingfishers fish from their banks, and Least Grebes and Masked Ducks breed here.  They are also an important habitat for wintering waterfowl.  We observed several species of duck here, including Cinnamon Teal (Anas cyanoptera), Green-winged Teal (Anas carolinensis), and Northern Shovelers (Anas clypeata).

IMG_1546

Cinnamon Teal

IMG_1770

Green-winged Teal

IMG_1873

Northern Shoveler

James and I spent one morning on our bellies in the tidal flats along the Gulf of Mexico.  We took advantage of the calm, shallow water to photograph foraging shorebirds and wading birds.  There were also large groups of Laughing Gulls, Royal Terns, and Black Skimmers Present.  After a while I had sand all over everything.  All over me, all over my camera.  So many grains of sand became trapped in the buttons of my camera that the shutter button became stuck in a depressed position.  As soon as I turned the camera on it would begin firing in rapid succession.  I was unable to change any settings.  Unfortunately as a result I missed some opportunities for shots of Marbled Godwits and a few other species.  Fortunately I was able to capture a few images prior to this malfunction, like this Short-billed Dowitcher (Limnodromus griseus) on the hunt for invertebrates.

IMG_7046

Short-billed Dowitcher

Perhaps my favorite of the long-legged wading birds, the Reddish Egret (Egretta rufescens) is an uncommon species that appears to be on the decline.  They are closely tied to coastal habitats, and most population estimates put the number of birds at less than 10,000 pairs globally.

IMG_7091

Reddish Egret

These handsome birds put on a truly spectacular show as they forage in the shallows.  They are famous for their graceful, acrobatic hunting technique. They seemingly dance upon the shallow water, running, turning, and waving their wings in a way that seems at the same time chaotic and choreographed. This technique startles small fish in the shallows, and the egrets will then cup their wings over their head to shade out the sun so that they may more easily spot their quarry.

IMG_7175

Reddish Egret oh the hunt

Fortunately, with the help of a needle and some compressed air, I was able to get the sand out of my shutter button, and captured many memorable photographs during our short time in the valley.  While we observed many spectacular landscapes and organisms on our trip, our time spent with the birds was truly special, and I’ll always cherish the memories of chasing after them, camera in hand.

One in the Hand, Two in Tobusch

IMG_5898

Tobusch Fishhook Cactus

This past weekend I spoke at the Native Plant Society of Texas Spring Symposium about photographing the biodiversity of Texas.  The symposium was in Austin, and happened to occur during the blooming period of the Federally Endangered Tobusch Fishhook Cactus (Sclerocactus brevihamatus ssp. tobuschii).  Though the cacti do not occur particularly close to Austin, it was the closest we would get for the foreseeable future, so Carolina and I decided we would stay an extra night in the Hill Country and try for the cactus the day after the symposium.

We arrive in Austin on Friday afternoon and took the day to explore the city.  While big cities are certainly not my thing, I really enjoyed visiting the Texas State Capitol building.  Plumes of Cedar Waxwings danced and buzzed among the many trees that decorated the capitol lawn and the redbuds were just coming into bloom.  Inside we marveled at the architecture and artwork, and took in the history of the place.

Saturday we rose early and made our way to the symposium.  We thoroughly enjoyed the event.  I saw some old friends and met a lot of friendly, interesting people.  The symposium was over by 3 or so, so Carolina and I took some time to explore the area.  Early spring wildflowers were just coming into bloom and Texas Spiny Lizards (Sceloporus olivaceus) were out basking on the limestone, though they did not take kindly to our approach.

In one of the many tributaries of the Colorado River we spotted a pair of Texas Map Turtles (Graptemys versa).  The Texas Map Turtle is one of a number of species of turtles endemic to central Texas.  This beautiful, fascinating species is restricted to the Colorado River basin.  The females are significantly larger than the males, and each sex has specialized head morphology to utilize different food sources.  Males feed primarily on aquatic insect larvae and other invertebrates, while adult females feed primarily on mollusks, shell and all.  We spotted the pair basking on some rocks, but the tiny male soon sank into the cool clear water.  The female allowed a slow approach as she took in the warmth of an early spring afternoon.

IMG_5564

Texas Map Turtle

That evening we made our way to San Antonio.  I wanted to show Carolina some of the old Spanish and German architecture of the city, and we would be closer to the cacti.  We spent some time exploring downtown, and grabbed a hotel on the outskirts of town.  The next morning we slept in.  Generally speaking, cacti flowers open midday in order to take advantage of the peak of pollinator activity.  Our destination was an hour and a half or so west of the Alamo City.  The path took us through the scenic country of the western Edwards Plateau, over oak and juniper hilltops, and down through rocky river valleys, where crystal clear water cut through limestone.

We finally arrived at a Tobusch Fishhook Cactus population that I had access to.  We began exploring.  It wasn’t long until I spotted the first cactus, and it was in bloom!  They were smaller than I had expecting, most being only a few inches across.  This cryptic species is extremely difficult to spot when not in bloom.  In late winter/early spring, however, they bloom, and their striking, albeit tiny, yellow flowers make them ever so slightly more conspicuous.

IMG_5665

Tobusch Fishhook Cactus

The story of the Tobusch Fishhook Cactus is an interesting one.  In the late 1970s there were only four known populations in two Texas counties.  In 1978 a flood hit and wiped out half of these populations in one fell swoop.  Fearing that S. brevihamatus ssp. tobuschii would soon be lost forever, the government afforded them protection under the Endangered Species Act in 1979, designated them a Federally Endangered Species.  At the time that it was listed it was believed to be restricted to limestone ledges and gravelly stream terraces adjacent to streams in just two Texas Counties.

IMG_5740

Tobusch Fishhok Cactus Flowers

Once it was listed, survey and conservation efforts were undertaken in earnest.  In the following decades several new populations were discovered, including many on protected land.  It also became evident that its habitat preferences were not as narrow as previously thought.  Today we know that it also occurs in shallow soils over slabs of limestone within clearings within a broader matrix of oak-juniper and oak-juniper-pinyon woodlands.  Many of these areas are well away from streams and their associated floodplains and terraces.

IMG_5753

Tobusch Fishhook Cactus

Armed with the knowledge that this diminutive cactus is doing better than previously thought, the US Fish and Wildlife Service proposed to downlist the Tobusch Fishhook Cactus from Endangered to Threatened in December 2016.  While this Texas endemic may be more common than initially thought, it still faces very real threats, and a number of historic populations have become extirpated, including the original populations at the time of listing.  Even in the face of these threats, today the future for this subspecies looks promising.

IMG_5900.jpg

Tobusch Fishhook Cactus

That day we would see many Tobusch Fishhooks, most of them in bloom.  In the sunny warmth of that spring afternoon the pollinators were out in force.  We watched as a variety of butterflies and bees bounced from flower to flower in search of the sweet nectar within.  Perhaps my favorite of these propagators were the metallic green sweat bees (Agopostemon sp.).  Their brilliant metallic sheen added the perfect compliment to the greenish yellow blooms of the cacti.

IMG_5874

Metallic Sweat Bee

The title of today’s blog comes from my good friend Toby Hibbitts.  Many of my friends enjoy a good pun as much as anyone should.  Last year after a friend posted a photo of the Tobusch Fishhook Cactus, Toby commented that he had always heard that “a bird in the hand is worth two in Tobusch”.  He was undoubtedly, and understandably pleased with himself.  I can only hope that this species persists for future generations of cactus lovers, naturalists, pollinators, weevils, and bad pun lovers to enjoy.

Vernal Pools: The Kingdom of the Amphibians

IMG_7548

Ovipositing Spotted Salamander

There are few things more magical, few moments more memorable, and few experiences more rewarding than exploring a vernal pool in late winter and early spring.  I wish everyone could know the joy that I feel standing ankle deep in the frigid water amid a deafening cacophony of Spring Peepers and chorus frogs.

Vernal pools are isolated wetlands that form in upland depressions.  In the great forests of the eastern United States, of which the Pineywoods of East Texas are essentially an extension, they often occur in open, mature forests over pockets of dense clay scattered among a matrix of otherwise loamy soil.  They may also occur in the scars of old stream beds left after some waterway changed course millennia ago.  The unique topography of these areas result in pools that hold water during the winter and spring and dry in the summer and fall.

15730847680_2678992e9c_o

A dry vernal pool in fall

Vernal pools begin to fill in the late fall and early winter with the return of regular rainfall patterns associated with frequent fronts.  At the same time trees and other plants are entering a period of dormancy, when their water requirements are reduced dramatically.  This reduction in plant activity results in a rising of the water table.  In more northerly climates the pools may not fill until the spring snow melt funnels water to them.  By later spring and early summer, the water table begins to drop as thirsty roots draw from it.  Evapotranspiration increases, and by late summer these depressions will be dry as a bone.

15710537833_064f0d2610_o

A full vernal pool in late winter

The ephemeral nature of these wetlands means that fish are unable to survive here.  This does not mean that vernal pools are devoid of life, however.  A multitude of invertebrates specialize in vernal pools and a spectacular array of amphibians depend on them to breed.  It is, in fact, the absence of fish that allow these organisms to thrive here.  Without these voracious piscene predators, and with an abundance of invertebrate prey, amphibian larvae can flourish.

Many amphibians typical of eastern North America reach the southwestern extend in East Texas.  Most of these species breed during the first substantial warm rains of late winter and early spring, often undergoing mass migrations from upland refugia to reach the vernal pools.  Easily the most spectacular of these amphibians, and perhaps my favorite animal of all time, is the Spotted Salamander (Ambystoma maculatum).  These large, brightly colored members of the family Ambystomatidae are like the “poster children” of vernal pools.  Their fate is so closely tied to these unique habitats that they are indicator species for them.  And as healthy vernal pools depend on a healthy, mature forest, the Spotted Salamander is, in turn, an indicator species for the health of the entire forest.

IMG_4760a

A male Spotted Salamander

Spotted salamanders spend the majority of their lives confined to small burrows, generally excavated by some species of rodent or other fossorial creature.  As the warm winter rains begin to saturate the soil they slowly emerge from their underground haunts and make their way, en masse, to the vernal pools of their birth.  The males arrive first.  They can be identified this time of year by their swollen cloacas.  When all is said and done they will outnumber the females several to one.  After entering the water they dutifully set out to find the perfect spot to deposit their spermatophore, a gelatinous deposit containing their genetic material.  Here they await the arrival of the females.

IMG_6969

A Spotted Salamander emerges from the leaf litter

When the females do arrive their are swollen with a gelatinous mass of eggs within.  The males dance and display around their spermatophore with a series of flips, gyrations, and underwater acrobatics.  Once they have caught the eye of a female they gently guide her over their spermatophore.  She picks it up with her cloaca and uses it to fertilize her eggs.  She then deposits an impossibly massive egg mass on a submerged twig or vegetation.  The salamanders do not dawdle in the ponds, and as soon as they arrived they return to their upland burrows.  Here they will remain for the rest of the year.  Part of what makes seeing a Spotted Salamander so special is knowing that they are only visible to the above-ground world for a few shorts weeks of the year.

The salamander eggs are protected by a thick gelatinous mass that is resistant to desiccation should the pool dry for a short time during their development.  The Spotted Salamander have a mutualistic relationship with an algae, Oophila amblystomatis, which is found exclusively within the salamanders’ egg masses.  The algae benefits from the nitrogen-rich waste products produced by the developing embryos while the embryos themselves are oxygenated through the biproducts of the photosynthesizing algae.

Eventually tiny, legless gilled salamander larvae will emerge from the egg masses.  They will feed and grow within the vernal pools until sometime in late spring when their legs and lungs are fulled developed.  They will then absorb their gills, lose their tail fins, and emerge from the water to begin a terrestrial life.

8402409478_a86a443db1_o

Spotted Salamander Egg Mass

There are other species of salamander that utilize vernal pools.  The Mole Salamander (Ambystoma talpoideum) is a small, stocky salamander of the southeastern United States.  They occur in a variety of ephemeral wetlands, from vernal pools to permanent fish-free ponds within longleaf pine savannahs.  Populations in East Texas often contain both terrestrial and neotenic adults.  In neoteny, adults retain juvnile characteristics; in this case gills and aquatic morphology.  These neotonic adults enjoy an entirely aquatic existence, even breeding in the water.  If the pool begins to drain, however, these aquatic adults can absorb their gills and morph into terrestrial adults.

15916197711_8c3aa62bf6_o

Mole Salamander

In East Texas, Smallmouth Salamanders (Ambystoma texanum) seem to be most common in large ephemeral wetland complexes in floodplain forests.  They will still utilize traditional vernal pools, however.  They are variable in pattern, having a variety of lichen-like blotches and flecks ranging from blue-gray to rusty brown.  In Texas they occur in scattered populations throughout much of the eastern third of the state.

8504912344_a8425cde79_o

Smallmouth Salamander

The Marbled Salamander (Ambystoma opacum) is an anomaly.  While the other Ambystomatid salamanders in East Texas breed in the late winter/early spring, the Marbled Salamander breeds in the fall, when the vernal pools are still dry.  During autumn’s first cool rains they migrate to the dry pool basins.  Here they breed on the land, and the female deposits her eggs on dry earth beneath logs and other natural debris within the depression.  Here she will stay, guarding her eggs, until the winter rains fill the pools and inundate the eggs.

15805943182_495be9eeda_o

A female Marbled Salamander guarding her eggs.

There is method to this madness, however.  By the time the eggs of the Spotted, Mole, and Smallmouth Salamanders have hatched, the Marbled Salamander larvae have been growing for weeks.  What ensues is a mass slaughter of intra-generic predation, as Marbled Salamander larvae consume hundreds of their congenerics.  This spring we observed hundreds of Spotted Salamander egg masses, and most had at least one Marbled Salamander larva sitting atop them.  For a short while at least, the Marbled Salamander is the king of the vernal pool.

IMG_0582a

A male Marbled Salamander

Marbled Salamander adults are sexually dimorphic.  Males have bright white to silvery dorsal markings while the markings of the female are a duller silver or copper.  Males arrive to the dry pools first, and as with the Spotted Salamander, significantly outnumber the females.

IMG_0492

Marbled Salamander male (upper right) and female (lower left)

The above mentioned salamanders all have fascinating life histories, but they pale in comparison to the complexity of the life cycle of the Central Newt (Nothophthalmus viridescens louisianensis).  The Central Newt starts life as an aquatic larva emerging from eggs laid in the water.  After a short time they morph into a terrestrial juvenile known as an “eft”.  During this time their skin is noticeably dry to the touch.  After spending a couple of years on land, these juveniles typically return to the water, where they will morph again into an aquatic adult.

8143022249_86466c821a_o

Central Newt Eft

To those exploring a vernal pool at night, their eyes are undoubtedly drawn to the salamanders swimming below the water’s surface.  Their ears, however, belong to the frogs.  Depending on the time of year, a multitude of intricate frog calls may ring out, often in deafening spectacularity.  One of the best known of these anurans is the Spring Peeper (Pseudacris crucifer).  These tiny harbingers of spring fill the night air with their peeping calls that seem too loud to come from such a tiny thing.

IMG_1094

Spring Peeper

Our East Texas representative of the Pseudacris feriarum complex is the Cajun Chorus Frog (Pseudacris fouquettei).  These diminutive frogs seem to breed just about anywhere that water remains for more than a few weeks.  Their call has been likened to a finger running through the teeth of a comb.  In my area P. fouquettei typically starts calling in early to mid December.  I have found many a good vernal pool by following the calls of the Cajun Chorus Frog.

IMG_7651

Cajun Chorus Frog

The Gray Tree Frogs (Hyla chrysoscelis and Hyla versicolor) typically begin breeding in mid Spring, later than the Spring Peeper and Cajun Chorus Frog.  The two species of Gray Tree Frog can only be differentiated by their calls.  In East Texas they typically begin calling in late February/Early March, and may call well into the summer following heavy rains.

17731409080_26e6386271_o (1)

Cope’s Gray Tree Frog (Hyla chrysoscelis)

Perhaps my favorite anuran inhabitant of vernal pools is the Pickerel Frog (Lithobates [Ranapalustris).  They can be differentiated from the similar Southern Leopard Frog by the two rows of large-block like blotches on their back and bright yellow inner legs.  While they are common throughout much of their range, the Pickerel Frog is uncommon in East Texas.  Along with the Southern Leopard Frog, it is one of the earliest breeding Ranids in the Pineywoods.  The Pickerel Frog is known for its toxicity.  Some people who handle these frogs report sensations from mild tingling to moderate pain in their fingers afterwards.  Fortunately I have never had a reaction.  They are also toxic to other amphibians, and may kill other species that are confined to plastic bags with them.

IMG_2404

Pickerel Frog

The Southern Leopard Frog (Lithobates sphenocephalus [Rana sphenocephala]) is one of our commonest Ranids.  I remember the first time I heard their haunting call.  I thought I was listening to some dispute between raccoons or some similar mammal.  Southern Leopard Frogs are quite variable, but their spots are always smaller and more randomly distributed than those of the Pickerel Frog.  They also lack the bright yellow inner legs of their toxic cousins.

30539138911_24c190cf75_o

Southern Leopard Frog

The annual amphibian migration to vernal pools is truly one of nature’s great spectacles.  I remember one night a few years ago when Carolina and I, accompanied by some of our closest friends, went out to a vernal pool at night.  A warm front had moved in, drenching East Texas with bands of rain throughout the day and into the night.  As we began travelling to our destination the rain began to pick up, and branched lightning descended from the clouds, dancing across the sky and illuminating the columns of shadow in the dark forest. I was full of anticipation and doubt as we approached the pond. Though the conditions seemed perfect, I had tried this very thing before and turned up empty handed.

Almost inexplicably, at nearly the exact moment we arrived at the pond, the rain had stopped. I rushed to the ponds edge, flashlight in hand. Immediately it became clear that all of my doubts were for naught. As my light crossed the leafy bottom of the vernal pool I could see hundreds of yellow spots; Spots decorating the backs of dozens of Spotted Salamanders that darted back and forth beneath the clear water. We did it, I thought, we timed it perfectly. The calm night was interrupted by the voices of innumerable Cajun chorus frogs that sang from the pool’s edge. It was, without a doubt, one of the most incredible natural events I had ever witnessed.

It was at that moment, when I thought that things couldn’t be more perfect, that my heart could not be more whole, that Carolina said, “look at the sky.” I looked up and saw that the clouds had broken, and in their wake the brilliance of millions of stars shone in the moonless night sky. And though I may be a secular person, the sensation I felt at that moment was no less profound than some deeply religious experience. For the most incredible moments in life need not be some miracle brought on by divine powers, but rather the countless natural wonders of the very world to which we all are a part.